【第二章】:数据类型
基本数据类型
一、整型
如: 18、73、84
整型具备如下功能:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class int(object): """ int(x=0) -> int or long int(x, base=10) -> int or long Convert a number or string to an integer, or return 0 if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is outside the integer range, the function returns a long instead. If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by '+' or '-' and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int('0b100', base=0) """ def bit_length(self): """ 返回表示该数字的时占用的最少位数 """ """ int.bit_length() -> int Number of bits necessary to represent self in binary. >>> bin(37) '0b100101' >>> (37).bit_length() """ return 0 def conjugate(self, *args, **kwargs): # real signature unknown """ 返回该复数的共轭复数 """ """ Returns self, the complex conjugate of any int. """ pass def __abs__(self): """ 返回绝对值 """ """ x.__abs__() <==> abs(x) """ pass def __add__(self, y): """ x.__add__(y) <==> x+y """ pass def __and__(self, y): """ x.__and__(y) <==> x&y """ pass def __cmp__(self, y): """ 比较两个数大小 """ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __coerce__(self, y): """ 强制生成一个元组 """ """ x.__coerce__(y) <==> coerce(x, y) """ pass def __divmod__(self, y): """ 相除,得到商和余数组成的元组 """ """ x.__divmod__(y) <==> divmod(x, y) """ pass def __div__(self, y): """ x.__div__(y) <==> x/y """ pass def __float__(self): """ 转换为浮点类型 """ """ x.__float__() <==> float(x) """ pass def __floordiv__(self, y): """ x.__floordiv__(y) <==> x//y """ pass def __format__(self, *args, **kwargs): # real signature unknown pass def __getattribute__(self, name): """ x.__getattribute__('name') <==> x.name """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown """ 内部调用 __new__方法或创建对象时传入参数使用 """ pass def __hash__(self): """如果对象object为哈希表类型,返回对象object的哈希值。哈希值为整数。在字典查找中,哈希值用于快速比较字典的键。两个数值如果相等,则哈希值也相等。""" """ x.__hash__() <==> hash(x) """ pass def __hex__(self): """ 返回当前数的 十六进制 表示 """ """ x.__hex__() <==> hex(x) """ pass def __index__(self): """ 用于切片,数字无意义 """ """ x[y:z] <==> x[y.__index__():z.__index__()] """ pass def __init__(self, x, base=10): # known special case of int.__init__ """ 构造方法,执行 x = 123 或 x = int(10) 时,自动调用,暂时忽略 """ """ int(x=0) -> int or long int(x, base=10) -> int or long Convert a number or string to an integer, or return 0 if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is outside the integer range, the function returns a long instead. If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by '+' or '-' and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int('0b100', base=0) # (copied from class doc) """ pass def __int__(self): """ 转换为整数 """ """ x.__int__() <==> int(x) """ pass def __invert__(self): """ x.__invert__() <==> ~x """ pass def __long__(self): """ 转换为长整数 """ """ x.__long__() <==> long(x) """ pass def __lshift__(self, y): """ x.__lshift__(y) <==> x<<y """ pass def __mod__(self, y): """ x.__mod__(y) <==> x%y """ pass def __mul__(self, y): """ x.__mul__(y) <==> x*y """ pass def __neg__(self): """ x.__neg__() <==> -x """ pass @staticmethod # known case of __new__ def __new__(S, *more): """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __nonzero__(self): """ x.__nonzero__() <==> x != 0 """ pass def __oct__(self): """ 返回改值的 八进制 表示 """ """ x.__oct__() <==> oct(x) """ pass def __or__(self, y): """ x.__or__(y) <==> x|y """ pass def __pos__(self): """ x.__pos__() <==> +x """ pass def __pow__(self, y, z=None): """ 幂,次方 """ """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """ pass def __radd__(self, y): """ x.__radd__(y) <==> y+x """ pass def __rand__(self, y): """ x.__rand__(y) <==> y&x """ pass def __rdivmod__(self, y): """ x.__rdivmod__(y) <==> divmod(y, x) """ pass def __rdiv__(self, y): """ x.__rdiv__(y) <==> y/x """ pass def __repr__(self): """转化为解释器可读取的形式 """ """ x.__repr__() <==> repr(x) """ pass def __str__(self): """转换为人阅读的形式,如果没有适于人阅读的解释形式的话,则返回解释器课阅读的形式""" """ x.__str__() <==> str(x) """ pass def __rfloordiv__(self, y): """ x.__rfloordiv__(y) <==> y//x """ pass def __rlshift__(self, y): """ x.__rlshift__(y) <==> y<<x """ pass def __rmod__(self, y): """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, y): """ x.__rmul__(y) <==> y*x """ pass def __ror__(self, y): """ x.__ror__(y) <==> y|x """ pass def __rpow__(self, x, z=None): """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ pass def __rrshift__(self, y): """ x.__rrshift__(y) <==> y>>x """ pass def __rshift__(self, y): """ x.__rshift__(y) <==> x>>y """ pass def __rsub__(self, y): """ x.__rsub__(y) <==> y-x """ pass def __rtruediv__(self, y): """ x.__rtruediv__(y) <==> y/x """ pass def __rxor__(self, y): """ x.__rxor__(y) <==> y^x """ pass def __sub__(self, y): """ x.__sub__(y) <==> x-y """ pass def __truediv__(self, y): """ x.__truediv__(y) <==> x/y """ pass def __trunc__(self, *args, **kwargs): """ 返回数值被截取为整形的值,在整形中无意义 """ pass def __xor__(self, y): """ x.__xor__(y) <==> x^y """ pass denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """ 分母 = 1 """ """the denominator of a rational number in lowest terms""" imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """ 虚数,无意义 """ """the imaginary part of a complex number""" numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """ 分子 = 数字大小 """ """the numerator of a rational number in lowest terms""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """ 实属,无意义 """ """the real part of a complex number""" int
二、长整型
如:2147483649、9223372036854775807
长整型具备如下功能:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class long(object): """ long(x=0) -> long long(x, base=10) -> long Convert a number or string to a long integer, or return 0L if no arguments are given. If x is floating point, the conversion truncates towards zero. If x is not a number or if base is given, then x must be a string or Unicode object representing an integer literal in the given base. The literal can be preceded by '+' or '-' and be surrounded by whitespace. The base defaults to 10. Valid bases are 0 and 2-36. Base 0 means to interpret the base from the string as an integer literal. >>> int('0b100', base=0) 4L """ def bit_length(self): # real signature unknown; restored from __doc__ """ long.bit_length() -> int or long Number of bits necessary to represent self in binary. >>> bin(37L) '0b100101' >>> (37L).bit_length() """ return 0 def conjugate(self, *args, **kwargs): # real signature unknown """ Returns self, the complex conjugate of any long. """ pass def __abs__(self): # real signature unknown; restored from __doc__ """ x.__abs__() <==> abs(x) """ pass def __add__(self, y): # real signature unknown; restored from __doc__ """ x.__add__(y) <==> x+y """ pass def __and__(self, y): # real signature unknown; restored from __doc__ """ x.__and__(y) <==> x&y """ pass def __cmp__(self, y): # real signature unknown; restored from __doc__ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __coerce__(self, y): # real signature unknown; restored from __doc__ """ x.__coerce__(y) <==> coerce(x, y) """ pass def __divmod__(self, y): # real signature unknown; restored from __doc__ """ x.__divmod__(y) <==> divmod(x, y) """ pass def __div__(self, y): # real signature unknown; restored from __doc__ """ x.__div__(y) <==> x/y """ pass def __float__(self): # real signature unknown; restored from __doc__ """ x.__float__() <==> float(x) """ pass def __floordiv__(self, y): # real signature unknown; restored from __doc__ """ x.__floordiv__(y) <==> x//y """ pass def __format__(self, *args, **kwargs): # real signature unknown pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __hash__(self): # real signature unknown; restored from __doc__ """ x.__hash__() <==> hash(x) """ pass def __hex__(self): # real signature unknown; restored from __doc__ """ x.__hex__() <==> hex(x) """ pass def __index__(self): # real signature unknown; restored from __doc__ """ x[y:z] <==> x[y.__index__():z.__index__()] """ pass def __init__(self, x=0): # real signature unknown; restored from __doc__ pass def __int__(self): # real signature unknown; restored from __doc__ """ x.__int__() <==> int(x) """ pass def __invert__(self): # real signature unknown; restored from __doc__ """ x.__invert__() <==> ~x """ pass def __long__(self): # real signature unknown; restored from __doc__ """ x.__long__() <==> long(x) """ pass def __lshift__(self, y): # real signature unknown; restored from __doc__ """ x.__lshift__(y) <==> x<<y """ pass def __mod__(self, y): # real signature unknown; restored from __doc__ """ x.__mod__(y) <==> x%y """ pass def __mul__(self, y): # real signature unknown; restored from __doc__ """ x.__mul__(y) <==> x*y """ pass def __neg__(self): # real signature unknown; restored from __doc__ """ x.__neg__() <==> -x """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __nonzero__(self): # real signature unknown; restored from __doc__ """ x.__nonzero__() <==> x != 0 """ pass def __oct__(self): # real signature unknown; restored from __doc__ """ x.__oct__() <==> oct(x) """ pass def __or__(self, y): # real signature unknown; restored from __doc__ """ x.__or__(y) <==> x|y """ pass def __pos__(self): # real signature unknown; restored from __doc__ """ x.__pos__() <==> +x """ pass def __pow__(self, y, z=None): # real signature unknown; restored from __doc__ """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """ pass def __radd__(self, y): # real signature unknown; restored from __doc__ """ x.__radd__(y) <==> y+x """ pass def __rand__(self, y): # real signature unknown; restored from __doc__ """ x.__rand__(y) <==> y&x """ pass def __rdivmod__(self, y): # real signature unknown; restored from __doc__ """ x.__rdivmod__(y) <==> divmod(y, x) """ pass def __rdiv__(self, y): # real signature unknown; restored from __doc__ """ x.__rdiv__(y) <==> y/x """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __rfloordiv__(self, y): # real signature unknown; restored from __doc__ """ x.__rfloordiv__(y) <==> y//x """ pass def __rlshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rlshift__(y) <==> y<<x """ pass def __rmod__(self, y): # real signature unknown; restored from __doc__ """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, y): # real signature unknown; restored from __doc__ """ x.__rmul__(y) <==> y*x """ pass def __ror__(self, y): # real signature unknown; restored from __doc__ """ x.__ror__(y) <==> y|x """ pass def __rpow__(self, x, z=None): # real signature unknown; restored from __doc__ """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ pass def __rrshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rrshift__(y) <==> y>>x """ pass def __rshift__(self, y): # real signature unknown; restored from __doc__ """ x.__rshift__(y) <==> x>>y """ pass def __rsub__(self, y): # real signature unknown; restored from __doc__ """ x.__rsub__(y) <==> y-x """ pass def __rtruediv__(self, y): # real signature unknown; restored from __doc__ """ x.__rtruediv__(y) <==> y/x """ pass def __rxor__(self, y): # real signature unknown; restored from __doc__ """ x.__rxor__(y) <==> y^x """ pass def __sizeof__(self, *args, **kwargs): # real signature unknown """ Returns size in memory, in bytes """ pass def __str__(self): # real signature unknown; restored from __doc__ """ x.__str__() <==> str(x) """ pass def __sub__(self, y): # real signature unknown; restored from __doc__ """ x.__sub__(y) <==> x-y """ pass def __truediv__(self, y): # real signature unknown; restored from __doc__ """ x.__truediv__(y) <==> x/y """ pass def __trunc__(self, *args, **kwargs): # real signature unknown """ Truncating an Integral returns itself. """ pass def __xor__(self, y): # real signature unknown; restored from __doc__ """ x.__xor__(y) <==> x^y """ pass denominator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the denominator of a rational number in lowest terms""" imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the imaginary part of a complex number""" numerator = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the numerator of a rational number in lowest terms""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the real part of a complex number""" long
注:跟C语言不同,Python的长整数没有指定位宽,即:Python没有限制长整数数值的大小,但实际上由于机器内存有限,我们使用的长整数数值不可能无限大。自从Python2.2起,如果整数发生溢出,Python会自动将整数数据转换为长整数,所以如今在长整数数据后面不加字母L也不会导致严重后果
三、浮点型
如:3.14、2.88
浮点型具备如下功能:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class float(object): """ float(x) -> floating point number Convert a string or number to a floating point number, if possible. """ def as_integer_ratio(self): """ 获取改值的最简比 """ """ float.as_integer_ratio() -> (int, int) Return a pair of integers, whose ratio is exactly equal to the original float and with a positive denominator. Raise OverflowError on infinities and a ValueError on NaNs. >>> (10.0).as_integer_ratio() (10, 1) >>> (0.0).as_integer_ratio() (0, 1) >>> (-.25).as_integer_ratio() (-1, 4) """ pass def conjugate(self, *args, **kwargs): # real signature unknown """ Return self, the complex conjugate of any float. """ pass def fromhex(self, string): """ 将十六进制字符串转换成浮点型 """ """ float.fromhex(string) -> float Create a floating-point number from a hexadecimal string. >>> float.fromhex('0x1.ffffp10') 2047.984375 >>> float.fromhex('-0x1p-1074') -4.9406564584124654e-324 """ return 0.0 def hex(self): """ 返回当前值的 16 进制表示 """ """ float.hex() -> string Return a hexadecimal representation of a floating-point number. >>> (-0.1).hex() '-0x1.999999999999ap-4' >>> 3.14159.hex() '0x1.921f9f01b866ep+1' """ return "" def is_integer(self, *args, **kwargs): # real signature unknown """ Return True if the float is an integer. """ pass def __abs__(self): """ x.__abs__() <==> abs(x) """ pass def __add__(self, y): """ x.__add__(y) <==> x+y """ pass def __coerce__(self, y): """ x.__coerce__(y) <==> coerce(x, y) """ pass def __divmod__(self, y): """ x.__divmod__(y) <==> divmod(x, y) """ pass def __div__(self, y): """ x.__div__(y) <==> x/y """ pass def __eq__(self, y): """ x.__eq__(y) <==> x==y """ pass def __float__(self): """ x.__float__() <==> float(x) """ pass def __floordiv__(self, y): """ x.__floordiv__(y) <==> x//y """ pass def __format__(self, format_spec): """ float.__format__(format_spec) -> string Formats the float according to format_spec. """ return "" def __getattribute__(self, name): """ x.__getattribute__('name') <==> x.name """ pass def __getformat__(self, typestr): """ float.__getformat__(typestr) -> string You probably don't want to use this function. It exists mainly to be used in Python's test suite. typestr must be 'double' or 'float'. This function returns whichever of 'unknown', 'IEEE, big-endian' or 'IEEE, little-endian' best describes the format of floating point numbers used by the C type named by typestr. """ return "" def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __ge__(self, y): """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): """ x.__gt__(y) <==> x>y """ pass def __hash__(self): """ x.__hash__() <==> hash(x) """ pass def __init__(self, x): pass def __int__(self): """ x.__int__() <==> int(x) """ pass def __le__(self, y): """ x.__le__(y) <==> x<=y """ pass def __long__(self): """ x.__long__() <==> long(x) """ pass def __lt__(self, y): """ x.__lt__(y) <==> x<y """ pass def __mod__(self, y): """ x.__mod__(y) <==> x%y """ pass def __mul__(self, y): """ x.__mul__(y) <==> x*y """ pass def __neg__(self): """ x.__neg__() <==> -x """ pass @staticmethod # known case of __new__ def __new__(S, *more): """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): """ x.__ne__(y) <==> x!=y """ pass def __nonzero__(self): """ x.__nonzero__() <==> x != 0 """ pass def __pos__(self): """ x.__pos__() <==> +x """ pass def __pow__(self, y, z=None): """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """ pass def __radd__(self, y): """ x.__radd__(y) <==> y+x """ pass def __rdivmod__(self, y): """ x.__rdivmod__(y) <==> divmod(y, x) """ pass def __rdiv__(self, y): """ x.__rdiv__(y) <==> y/x """ pass def __repr__(self): """ x.__repr__() <==> repr(x) """ pass def __rfloordiv__(self, y): """ x.__rfloordiv__(y) <==> y//x """ pass def __rmod__(self, y): """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, y): """ x.__rmul__(y) <==> y*x """ pass def __rpow__(self, x, z=None): """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """ pass def __rsub__(self, y): """ x.__rsub__(y) <==> y-x """ pass def __rtruediv__(self, y): """ x.__rtruediv__(y) <==> y/x """ pass def __setformat__(self, typestr, fmt): """ float.__setformat__(typestr, fmt) -> None You probably don't want to use this function. It exists mainly to be used in Python's test suite. typestr must be 'double' or 'float'. fmt must be one of 'unknown', 'IEEE, big-endian' or 'IEEE, little-endian', and in addition can only be one of the latter two if it appears to match the underlying C reality. Override the automatic determination of C-level floating point type. This affects how floats are converted to and from binary strings. """ pass def __str__(self): """ x.__str__() <==> str(x) """ pass def __sub__(self, y): """ x.__sub__(y) <==> x-y """ pass def __truediv__(self, y): """ x.__truediv__(y) <==> x/y """ pass def __trunc__(self, *args, **kwargs): # real signature unknown """ Return the Integral closest to x between 0 and x. """ pass imag = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the imaginary part of a complex number""" real = property(lambda self: object(), lambda self, v: None, lambda self: None) # default """the real part of a complex number""" float
四、字符串
如:'wupeiqi'、'alex'、'lzl'
1、字符串常用功能:
#!/usr/bin/env python # -*- coding:utf-8 -*- #-Author-Lian #str功能操作 name = "my name is lzl" print(name.capitalize()) #首字母大写 #My name is lzl print(name.count("l")) #统计字符串出现某个字符的个数 #2 print(name.center(30,"-")) #打印30个字符,不够的-补齐 #--------my name is lzl-------- print(name.ljust(30,"-")) #打印30个字符,不够的-补齐,字符串在左边 #my name is lzl---------------- print(name.endswith("lzl")) #判断字符串是否以lzl结尾 #True print(name[name.find("na"):]) #find寻找na所在的索引下标 字符串也可以切片 #name is lzl print("5.3".isdigit()) #判断字符是否为整数 #False print("a_1A".isidentifier()) #判断是不是一个合法的标识符(变量名) #True print("+".join(["1","2","3"])) #把join后的内容加入到前面字符串中,以+为分割符 #1+2+3 print("\nlzl".strip()) #去换行符 #lzl print("1+2+3+4".split("+")) #以+为分隔符生成新的列表,默认不写为空格 #['1', '2', '3', '4'] name = "my name is {name} and i an {year} old" print(name.format(name="lzl",year=20) #my name is lzl and i an 20 old print(name.format_map({"name":"lzl","year":20})) #很少用 #my name is lzl and i an 20 old p = str.maketrans("abcdefli","12345678") #转换 一一对应 print("lianzhilei".translate(p)) #781nzh8758
2、扩展
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class str(basestring): """ str(object='') -> string Return a nice string representation of the object. If the argument is a string, the return value is the same object. """ def capitalize(self): """ 首字母变大写 """ """ S.capitalize() -> string Return a copy of the string S with only its first character capitalized. """ return "" def center(self, width, fillchar=None): """ 内容居中,width:总长度;fillchar:空白处填充内容,默认无 """ """ S.center(width[, fillchar]) -> string Return S centered in a string of length width. Padding is done using the specified fill character (default is a space) """ return "" def count(self, sub, start=None, end=None): """ 子序列个数 """ """ S.count(sub[, start[, end]]) -> int Return the number of non-overlapping occurrences of substring sub in string S[start:end]. Optional arguments start and end are interpreted as in slice notation. """ return 0 def decode(self, encoding=None, errors=None): """ 解码 """ """ S.decode([encoding[,errors]]) -> object Decodes S using the codec registered for encoding. encoding defaults to the default encoding. errors may be given to set a different error handling scheme. Default is 'strict' meaning that encoding errors raise a UnicodeDecodeError. Other possible values are 'ignore' and 'replace' as well as any other name registered with codecs.register_error that is able to handle UnicodeDecodeErrors. """ return object() def encode(self, encoding=None, errors=None): """ 编码,针对unicode """ """ S.encode([encoding[,errors]]) -> object Encodes S using the codec registered for encoding. encoding defaults to the default encoding. errors may be given to set a different error handling scheme. Default is 'strict' meaning that encoding errors raise a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and 'xmlcharrefreplace' as well as any other name registered with codecs.register_error that is able to handle UnicodeEncodeErrors. """ return object() def endswith(self, suffix, start=None, end=None): """ 是否以 xxx 结束 """ """ S.endswith(suffix[, start[, end]]) -> bool Return True if S ends with the specified suffix, False otherwise. With optional start, test S beginning at that position. With optional end, stop comparing S at that position. suffix can also be a tuple of strings to try. """ return False def expandtabs(self, tabsize=None): """ 将tab转换成空格,默认一个tab转换成8个空格 """ """ S.expandtabs([tabsize]) -> string Return a copy of S where all tab characters are expanded using spaces. If tabsize is not given, a tab size of 8 characters is assumed. """ return "" def find(self, sub, start=None, end=None): """ 寻找子序列位置,如果没找到,返回 -1 """ """ S.find(sub [,start [,end]]) -> int Return the lowest index in S where substring sub is found, such that sub is contained within S[start:end]. Optional arguments start and end are interpreted as in slice notation. Return -1 on failure. """ return 0 def format(*args, **kwargs): # known special case of str.format """ 字符串格式化,动态参数,将函数式编程时细说 """ """ S.format(*args, **kwargs) -> string Return a formatted version of S, using substitutions from args and kwargs. The substitutions are identified by braces ('{' and '}'). """ pass def index(self, sub, start=None, end=None): """ 子序列位置,如果没找到,报错 """ S.index(sub [,start [,end]]) -> int Like S.find() but raise ValueError when the substring is not found. """ return 0 def isalnum(self): """ 是否是字母和数字 """ """ S.isalnum() -> bool Return True if all characters in S are alphanumeric and there is at least one character in S, False otherwise. """ return False def isalpha(self): """ 是否是字母 """ """ S.isalpha() -> bool Return True if all characters in S are alphabetic and there is at least one character in S, False otherwise. """ return False def isdigit(self): """ 是否是数字 """ """ S.isdigit() -> bool Return True if all characters in S are digits and there is at least one character in S, False otherwise. """ return False def islower(self): """ 是否小写 """ """ S.islower() -> bool Return True if all cased characters in S are lowercase and there is at least one cased character in S, False otherwise. """ return False def isspace(self): """ S.isspace() -> bool Return True if all characters in S are whitespace and there is at least one character in S, False otherwise. """ return False def istitle(self): """ S.istitle() -> bool Return True if S is a titlecased string and there is at least one character in S, i.e. uppercase characters may only follow uncased characters and lowercase characters only cased ones. Return False otherwise. """ return False def isupper(self): """ S.isupper() -> bool Return True if all cased characters in S are uppercase and there is at least one cased character in S, False otherwise. """ return False def join(self, iterable): """ 连接 """ """ S.join(iterable) -> string Return a string which is the concatenation of the strings in the iterable. The separator between elements is S. """ return "" def ljust(self, width, fillchar=None): """ 内容左对齐,右侧填充 """ """ S.ljust(width[, fillchar]) -> string Return S left-justified in a string of length width. Padding is done using the specified fill character (default is a space). """ return "" def lower(self): """ 变小写 """ """ S.lower() -> string Return a copy of the string S converted to lowercase. """ return "" def lstrip(self, chars=None): """ 移除左侧空白 """ """ S.lstrip([chars]) -> string or unicode Return a copy of the string S with leading whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def partition(self, sep): """ 分割,前,中,后三部分 """ """ S.partition(sep) -> (head, sep, tail) Search for the separator sep in S, and return the part before it, the separator itself, and the part after it. If the separator is not found, return S and two empty strings. """ pass def replace(self, old, new, count=None): """ 替换 """ """ S.replace(old, new[, count]) -> string Return a copy of string S with all occurrences of substring old replaced by new. If the optional argument count is given, only the first count occurrences are replaced. """ return "" def rfind(self, sub, start=None, end=None): """ S.rfind(sub [,start [,end]]) -> int Return the highest index in S where substring sub is found, such that sub is contained within S[start:end]. Optional arguments start and end are interpreted as in slice notation. Return -1 on failure. """ return 0 def rindex(self, sub, start=None, end=None): """ S.rindex(sub [,start [,end]]) -> int Like S.rfind() but raise ValueError when the substring is not found. """ return 0 def rjust(self, width, fillchar=None): """ S.rjust(width[, fillchar]) -> string Return S right-justified in a string of length width. Padding is done using the specified fill character (default is a space) """ return "" def rpartition(self, sep): """ S.rpartition(sep) -> (head, sep, tail) Search for the separator sep in S, starting at the end of S, and return the part before it, the separator itself, and the part after it. If the separator is not found, return two empty strings and S. """ pass def rsplit(self, sep=None, maxsplit=None): """ S.rsplit([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the delimiter string, starting at the end of the string and working to the front. If maxsplit is given, at most maxsplit splits are done. If sep is not specified or is None, any whitespace string is a separator. """ return [] def rstrip(self, chars=None): """ S.rstrip([chars]) -> string or unicode Return a copy of the string S with trailing whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def split(self, sep=None, maxsplit=None): """ 分割, maxsplit最多分割几次 """ """ S.split([sep [,maxsplit]]) -> list of strings Return a list of the words in the string S, using sep as the delimiter string. If maxsplit is given, at most maxsplit splits are done. If sep is not specified or is None, any whitespace string is a separator and empty strings are removed from the result. """ return [] def splitlines(self, keepends=False): """ 根据换行分割 """ """ S.splitlines(keepends=False) -> list of strings Return a list of the lines in S, breaking at line boundaries. Line breaks are not included in the resulting list unless keepends is given and true. """ return [] def startswith(self, prefix, start=None, end=None): """ 是否起始 """ """ S.startswith(prefix[, start[, end]]) -> bool Return True if S starts with the specified prefix, False otherwise. With optional start, test S beginning at that position. With optional end, stop comparing S at that position. prefix can also be a tuple of strings to try. """ return False def strip(self, chars=None): """ 移除两段空白 """ """ S.strip([chars]) -> string or unicode Return a copy of the string S with leading and trailing whitespace removed. If chars is given and not None, remove characters in chars instead. If chars is unicode, S will be converted to unicode before stripping """ return "" def swapcase(self): """ 大写变小写,小写变大写 """ """ S.swapcase() -> string Return a copy of the string S with uppercase characters converted to lowercase and vice versa. """ return "" def title(self): """ S.title() -> string Return a titlecased version of S, i.e. words start with uppercase characters, all remaining cased characters have lowercase. """ return "" def translate(self, table, deletechars=None): """ 转换,需要先做一个对应表,最后一个表示删除字符集合 intab = "aeiou" outtab = "12345" trantab = maketrans(intab, outtab) str = "this is string example....wow!!!" print str.translate(trantab, 'xm') """ """ S.translate(table [,deletechars]) -> string Return a copy of the string S, where all characters occurring in the optional argument deletechars are removed, and the remaining characters have been mapped through the given translation table, which must be a string of length 256 or None. If the table argument is None, no translation is applied and the operation simply removes the characters in deletechars. """ return "" def upper(self): """ S.upper() -> string Return a copy of the string S converted to uppercase. """ return "" def zfill(self, width): """方法返回指定长度的字符串,原字符串右对齐,前面填充0。""" """ S.zfill(width) -> string Pad a numeric string S with zeros on the left, to fill a field of the specified width. The string S is never truncated. """ return "" def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown pass def _formatter_parser(self, *args, **kwargs): # real signature unknown pass def __add__(self, y): """ x.__add__(y) <==> x+y """ pass def __contains__(self, y): """ x.__contains__(y) <==> y in x """ pass def __eq__(self, y): """ x.__eq__(y) <==> x==y """ pass def __format__(self, format_spec): """ S.__format__(format_spec) -> string Return a formatted version of S as described by format_spec. """ return "" def __getattribute__(self, name): """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): """ x.__getitem__(y) <==> x[y] """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __getslice__(self, i, j): """ x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported. """ pass def __ge__(self, y): """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): """ x.__gt__(y) <==> x>y """ pass def __hash__(self): """ x.__hash__() <==> hash(x) """ pass def __init__(self, string=''): # known special case of str.__init__ """ str(object='') -> string Return a nice string representation of the object. If the argument is a string, the return value is the same object. # (copied from class doc) """ pass def __len__(self): """ x.__len__() <==> len(x) """ pass def __le__(self, y): """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): """ x.__lt__(y) <==> x<y """ pass def __mod__(self, y): """ x.__mod__(y) <==> x%y """ pass def __mul__(self, n): """ x.__mul__(n) <==> x*n """ pass @staticmethod # known case of __new__ def __new__(S, *more): """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): """ x.__repr__() <==> repr(x) """ pass def __rmod__(self, y): """ x.__rmod__(y) <==> y%x """ pass def __rmul__(self, n): """ x.__rmul__(n) <==> n*x """ pass def __sizeof__(self): """ S.__sizeof__() -> size of S in memory, in bytes """ pass def __str__(self): """ x.__str__() <==> str(x) """ pass str
3、字符编码和转码,bytes和str区别
Python 3最重要的新特性大概要算是对文本和二进制数据作了更为清晰的区分。文本总是Unicode,由str类型表示,二进制数据则由bytes类型表示。Python 3不会以任意隐式的方式混用str和bytes(类似int和long之间自动转换),正是这使得两者的区分特别清晰。你不能拼接字符串和字节包,也无法在字节包里搜索字符串(反之亦然),也不能将字符串传入参数为字节包的函数(反之亦然)。这是件好事。不管怎样,字符串和字节包之间的界线是必然的,下面的图解非常重要,务请牢记于心:
字符串可以编码成字节包,而字节包可以解码成字符串:
#!/usr/bin/env python # -*- coding:utf-8 -*- #-Author-Lian msg = "里约奥运" print(msg.encode("utf-8")) #如果不指定编码格式,默认为utf-8 #b'\xe9\x87\x8c\xe7\xba\xa6\xe5\xa5\xa5\xe8\xbf\x90' print(b'\xe9\x87\x8c\xe7\xba\xa6\xe5\xa5\xa5\xe8\xbf\x90'.decode("utf-8")) #里约奥运
五、列表
如:[11,22,33,44,55]、['wupeiqi', 'alex','lzl']
1、创建列表:
#两种创建方式 name_list = ['alex', 'seven', 'eric'] print(name_list) # ['alex', 'seven', 'eric'] name_list = list(['alex', 'seven', 'eric']) print(name_list) # ['alex', 'seven', 'eric']
2、列表类常用功能:
① 切片
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] print(name_list[0:3]) #取下标0至下标3之间的元素,包括0,不包括3 #['Alex', 'Tenglan', 'Eric'] print(name_list[:3]) #:前什么都不写,表示从0开始,效果跟上句一样 #['Alex', 'Tenglan', 'Eric'] print(name_list[3:]) #:后什么不写,表示取值到最后 #['Rain', 'Tom', 'Amy'] print(name_list[:]) #:前后都不写,表示取值所有 #['Alex', 'Tenglan', 'Eric', 'Rain', 'Tom', 'Amy'] print(name_list[-3:-1]) #从-3开始到-1,包括-3,不包括-1 #['Rain', 'Tom'] print(name_list[1:-1]) #从1开始到-1,下标有正有负时,正数在前负数在后 #['Tenglan', 'Eric', 'Rain', 'Tom'] print(name_list[::2]) #2表示,每个1个元素,就取一个 #['Alex', 'Eric', 'Tom'] #注:[-1:0] [0:0] [-1:2] 都是空
② 追加
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] name_list.append("new") #append追加,加到最后,只能添加一个 print(name_list) #['Alex', 'Tenglan', 'Eric', 'Rain', 'Tom', 'Amy', 'new']
③ 插入
#插入 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] name_list.insert(3,"new") #insert插入,把"new"加到下标3的位置 print(name_list)
④ 修改
#修改 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] name_list[2] = "lzl" #把下标2的字符串换成lzl print(name_list)
⑤ 删除
#3种删除方式 name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] del name_list[3] #del删除,指定要删除的下标 print(name_list) #['Alex', 'Tenglan', 'Eric', 'Tom', 'Amy'] name_list.remove("Tenglan") #remove删除,指定要删除的字符 print(name_list) #['Alex', 'Eric', 'Tom', 'Amy'] name_list.pop() #pop删除,删除列表最后一个值 print(name_list) #['Alex', 'Eric', 'Tom']
⑥ 扩展
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] age_list = [11,22,33] name_list.extend(age_list) #extend扩展,把列表age_list添加到name_list列表 print(name_list)
⑦ 拷贝
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] copy_list = name_list.copy() #copy拷贝,对列表进行复制 print(copy_list) #注:博客最下有关于深浅copy的详细区分
⑧ 统计
name_list = ["Alex","Tenglan","Eric","Amy","Tom","Amy"] print(name_list.count("Amy")) #count统计,统计列表Amy的个数 #2
⑨ 排序和翻转
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy","1","2","3"] name_list.sort() #sort排序,对列表进行排序 print(name_list) #['1', '2', '3', 'Alex', 'Amy', 'Eric', 'Rain', 'Tenglan', 'Tom'] name_list.reverse() #reverse翻转,对列表进行翻转 print(name_list) #['Tom', 'Tenglan', 'Rain', 'Eric', 'Amy', 'Alex', '3', '2', '1']
⑩ 获取下标
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] print(name_list.index("Tenglan")) #index索引,获取字符的下标 #1
⑪ 同时获取下标和值
name_list = ["Alex","Tenglan","Eric","Rain","Tom","Amy"] for index,item in enumerate(name_list): #index索引,获取字符的下标 print(index,item) # 0 Alex # 1 Tenglan # 2 Eric # 3 Rain # 4 Tom # 5 Amy
3、扩展
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class list(object): """ list() -> new empty list list(iterable) -> new list initialized from iterable's items """ def append(self, p_object): # real signature unknown; restored from __doc__ """ L.append(object) -- append object to end """ pass def count(self, value): # real signature unknown; restored from __doc__ """ L.count(value) -> integer -- return number of occurrences of value """ return 0 def extend(self, iterable): # real signature unknown; restored from __doc__ """ L.extend(iterable) -- extend list by appending elements from the iterable """ pass def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__ """ L.index(value, [start, [stop]]) -> integer -- return first index of value. Raises ValueError if the value is not present. """ return 0 def insert(self, index, p_object): # real signature unknown; restored from __doc__ """ L.insert(index, object) -- insert object before index """ pass def pop(self, index=None): # real signature unknown; restored from __doc__ """ L.pop([index]) -> item -- remove and return item at index (default last). Raises IndexError if list is empty or index is out of range. """ pass def remove(self, value): # real signature unknown; restored from __doc__ """ L.remove(value) -- remove first occurrence of value. Raises ValueError if the value is not present. """ pass def reverse(self): # real signature unknown; restored from __doc__ """ L.reverse() -- reverse *IN PLACE* """ pass def sort(self, cmp=None, key=None, reverse=False): # real signature unknown; restored from __doc__ """ L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*; cmp(x, y) -> -1, 0, 1 """ pass def __add__(self, y): # real signature unknown; restored from __doc__ """ x.__add__(y) <==> x+y """ pass def __contains__(self, y): # real signature unknown; restored from __doc__ """ x.__contains__(y) <==> y in x """ pass def __delitem__(self, y): # real signature unknown; restored from __doc__ """ x.__delitem__(y) <==> del x[y] """ pass def __delslice__(self, i, j): # real signature unknown; restored from __doc__ """ x.__delslice__(i, j) <==> del x[i:j] Use of negative indices is not supported. """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ pass def __getslice__(self, i, j): # real signature unknown; restored from __doc__ """ x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported. """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __iadd__(self, y): # real signature unknown; restored from __doc__ """ x.__iadd__(y) <==> x+=y """ pass def __imul__(self, y): # real signature unknown; restored from __doc__ """ x.__imul__(y) <==> x*=y """ pass def __init__(self, seq=()): # known special case of list.__init__ """ list() -> new empty list list(iterable) -> new list initialized from iterable's items # (copied from class doc) """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass def __mul__(self, n): # real signature unknown; restored from __doc__ """ x.__mul__(n) <==> x*n """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __reversed__(self): # real signature unknown; restored from __doc__ """ L.__reversed__() -- return a reverse iterator over the list """ pass def __rmul__(self, n): # real signature unknown; restored from __doc__ """ x.__rmul__(n) <==> n*x """ pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__ """ x.__setitem__(i, y) <==> x[i]=y """ pass def __setslice__(self, i, j, y): # real signature unknown; restored from __doc__ """ x.__setslice__(i, j, y) <==> x[i:j]=y Use of negative indices is not supported. """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ L.__sizeof__() -- size of L in memory, in bytes """ pass __hash__ = None list
六、元组
如:(11,22,33,44,55)、('wupeiqi', 'alex','lzl')
1、创建元组:
#5种创建方式 age = 11,22,33,44,55 #直接写数字或者字符串,默认创建类型元组 字符串类型用引号'lzl' #输出: (11, 22, 33, 44, 55) age = (11,22,33,44,55) #常见命名方式,()指定类型元组 #输出: (11, 22, 33, 44, 55) age = tuple((11,22,33,44,55)) #tuple 以类的方式创建(()) 双括号 里面的()不可去掉 #输出: (11, 22, 33, 44, 55) age = tuple([11,22,33,44,55]) #同(()) 效果一样 很少用 忘记它 #输出: (11, 22, 33, 44, 55) age = tuple({11,22,33,44,55}) #({})创建的元组,随机排列 没卵用 #输出: (33, 11, 44, 22, 55)
2、元组类常用功能:
##count #统计元组字符出现的次数 name = ('wupeiqi', 'alex','lzl') print(name.count('alex')) # 1 ##index #查看字符串所在的索引位置 name = ('wupeiqi', 'alex','lzl') print(name.index('lzl')) # 2
3、扩展:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class tuple(object): """ tuple() -> empty tuple tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object. """ def count(self, value): # real signature unknown; restored from __doc__ """ T.count(value) -> integer -- return number of occurrences of value """ return 0 def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__ """ T.index(value, [start, [stop]]) -> integer -- return first index of value. Raises ValueError if the value is not present. """ return 0 def __add__(self, y): # real signature unknown; restored from __doc__ """ x.__add__(y) <==> x+y """ pass def __contains__(self, y): # real signature unknown; restored from __doc__ """ x.__contains__(y) <==> y in x """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ pass def __getnewargs__(self, *args, **kwargs): # real signature unknown pass def __getslice__(self, i, j): # real signature unknown; restored from __doc__ """ x.__getslice__(i, j) <==> x[i:j] Use of negative indices is not supported. """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __hash__(self): # real signature unknown; restored from __doc__ """ x.__hash__() <==> hash(x) """ pass def __init__(self, seq=()): # known special case of tuple.__init__ """ tuple() -> empty tuple tuple(iterable) -> tuple initialized from iterable's items If the argument is a tuple, the return value is the same object. # (copied from class doc) """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass def __mul__(self, n): # real signature unknown; restored from __doc__ """ x.__mul__(n) <==> x*n """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __rmul__(self, n): # real signature unknown; restored from __doc__ """ x.__rmul__(n) <==> n*x """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ T.__sizeof__() -- size of T in memory, in bytes """ pass tuple
七、字典 无序
如:{'name': 'wupeiqi', 'age': 18} 、{'host': '2.2.2.2', 'port': 80}
注:字典一种key:value 的数据类型,也称键值对。字典dict是无序的,key值必须是唯一的,不能有重复。循环时,默认循环的是key
#两种创建方式: info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",} print(info_dic) #{'stu1102': 'LongZe Luola', 'stu1101': 'TengLan Wu', 'stu1103': 'XiaoZe Maliya'} info_dic = dict({'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",}) print(info_dic) #{'stu1102': 'LongZe Luola', 'stu1101': 'TengLan Wu', 'stu1103': 'XiaoZe Maliya'}
2、字典类常用功能:
① 增加
# 第一种方式 info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",} info_dic['stu1104'] = "JingKong Cang" #增加 print(info_dic) # {'stu1102': 'LongZe Luola', 'stu1104': 'JingKong Cang', 'stu1103': 'XiaoZe Maliya', 'stu1101': 'TengLan Wu'} # 第二种方式 dic = {} d1={'k1':1} d2={'k2':2} dic.update(d1) dic.update(d2) print(dic) # {'k1': 1, 'k2': 2}
② 修改
info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",} info_dic["stu1101"] = "Jingkong Cang" #有相应的key时为修改,没有为增加 print(info_dic)
③ 删除
#3种删除方式 info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",} info_dic.pop('stu1101') #pop删除,指定删除的key print(info_dic) #{'stu1103': 'XiaoZe Maliya', 'stu1102': 'LongZe Luola'} del info_dic['stu1102'] #del删除,指定删除的key print(info_dic) #{'stu1103': 'XiaoZe Maliya'} info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",} info_dic.popitem() #随机删除,没卵用 print(info_dic) #{'stu1101': 'TengLan Wu', 'stu1103': 'XiaoZe Maliya'}
④ 查找value值
info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",} print(info_dic.get('stu1102')) #get查找,通过key查找value值 #LongZe Luola print(info_dic['stu1102']) #通过key直接查找,但是如果输入查找的key不存在的话,就会报错,get则不会 #LongZe Luola
⑤ 字典多级嵌套
av_catalog = { "欧美":{ "www.youpor1n.com": ["很多免费的,世界最大的","质量一般"], "www.por1nhub.com": ["很多免费的,也很大","质量比yourpor1n高点"], "letmedothistoyou.com": ["多是自拍,高质量图片很多","资源不多,更新慢"], "x-art.com":["质量很高,真的很高","全部收费,屌比请绕过"] }, "日韩":{ "tokyo-hot":["质量怎样不清楚,个人已经不喜欢日韩范了","听说是收费的"] }, "大陆":{ "1024":["全部免费,真好,好人一生平安","服务器在国外,慢"] } } av_catalog["大陆"]["1024"][1] += ",可以用爬虫爬下来" print(av_catalog["大陆"]["1024"]) #['全部免费,真好,好人一生平安', '服务器在国外,慢,可以用爬虫爬下来']
⑥ 循环
info_dic = {'stu1101': "TengLan Wu",'stu1102': "LongZe Luola",'stu1103': "XiaoZe Maliya",} for stu_nu in info_dic: print(stu_nu,info_dic[stu_nu]) #循环默认提取的是key #stu1103 XiaoZe Maliya #stu1101 TengLan Wu #stu1102 LongZe Luola for k,v in info_dic.items(): #先把dict生成list,数据量大的时候费时,不建议使用 print(k,v) #stu1103 XiaoZe Maliya #stu1101 TengLan Wu #stu1102 LongZe Luola
3、扩展
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class dict(object): """ dict() -> new empty dictionary dict(mapping) -> new dictionary initialized from a mapping object's (key, value) pairs dict(iterable) -> new dictionary initialized as if via: d = {} for k, v in iterable: d[k] = v dict(**kwargs) -> new dictionary initialized with the name=value pairs in the keyword argument list. For example: dict(one=1, two=2) """ def clear(self): # real signature unknown; restored from __doc__ """ 清除内容 """ """ D.clear() -> None. Remove all items from D. """ pass def copy(self): # real signature unknown; restored from __doc__ """ 浅拷贝 """ """ D.copy() -> a shallow copy of D """ pass @staticmethod # known case def fromkeys(S, v=None): # real signature unknown; restored from __doc__ """ dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v. v defaults to None. """ pass def get(self, k, d=None): # real signature unknown; restored from __doc__ """ 根据key获取值,d是默认值 """ """ D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None. """ pass def has_key(self, k): # real signature unknown; restored from __doc__ """ 是否有key """ """ D.has_key(k) -> True if D has a key k, else False """ return False def items(self): # real signature unknown; restored from __doc__ """ 所有项的列表形式 """ """ D.items() -> list of D's (key, value) pairs, as 2-tuples """ return [] def iteritems(self): # real signature unknown; restored from __doc__ """ 项可迭代 """ """ D.iteritems() -> an iterator over the (key, value) items of D """ pass def iterkeys(self): # real signature unknown; restored from __doc__ """ key可迭代 """ """ D.iterkeys() -> an iterator over the keys of D """ pass def itervalues(self): # real signature unknown; restored from __doc__ """ value可迭代 """ """ D.itervalues() -> an iterator over the values of D """ pass def keys(self): # real signature unknown; restored from __doc__ """ 所有的key列表 """ """ D.keys() -> list of D's keys """ return [] def pop(self, k, d=None): # real signature unknown; restored from __doc__ """ 获取并在字典中移除 """ """ D.pop(k[,d]) -> v, remove specified key and return the corresponding value. If key is not found, d is returned if given, otherwise KeyError is raised """ pass def popitem(self): # real signature unknown; restored from __doc__ """ 获取并在字典中移除 """ """ D.popitem() -> (k, v), remove and return some (key, value) pair as a 2-tuple; but raise KeyError if D is empty. """ pass def setdefault(self, k, d=None): # real signature unknown; restored from __doc__ """ 如果key不存在,则创建,如果存在,则返回已存在的值且不修改 """ """ D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """ pass def update(self, E=None, **F): # known special case of dict.update """ 更新 {'name':'alex', 'age': 18000} [('name','sbsbsb'),] """ """ D.update([E, ]**F) -> None. Update D from dict/iterable E and F. If E present and has a .keys() method, does: for k in E: D[k] = E[k] If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v In either case, this is followed by: for k in F: D[k] = F[k] """ pass def values(self): # real signature unknown; restored from __doc__ """ 所有的值 """ """ D.values() -> list of D's values """ return [] def viewitems(self): # real signature unknown; restored from __doc__ """ 所有项,只是将内容保存至view对象中 """ """ D.viewitems() -> a set-like object providing a view on D's items """ pass def viewkeys(self): # real signature unknown; restored from __doc__ """ D.viewkeys() -> a set-like object providing a view on D's keys """ pass def viewvalues(self): # real signature unknown; restored from __doc__ """ D.viewvalues() -> an object providing a view on D's values """ pass def __cmp__(self, y): # real signature unknown; restored from __doc__ """ x.__cmp__(y) <==> cmp(x,y) """ pass def __contains__(self, k): # real signature unknown; restored from __doc__ """ D.__contains__(k) -> True if D has a key k, else False """ return False def __delitem__(self, y): # real signature unknown; restored from __doc__ """ x.__delitem__(y) <==> del x[y] """ pass def __eq__(self, y): # real signature unknown; restored from __doc__ """ x.__eq__(y) <==> x==y """ pass def __getattribute__(self, name): # real signature unknown; restored from __doc__ """ x.__getattribute__('name') <==> x.name """ pass def __getitem__(self, y): # real signature unknown; restored from __doc__ """ x.__getitem__(y) <==> x[y] """ pass def __ge__(self, y): # real signature unknown; restored from __doc__ """ x.__ge__(y) <==> x>=y """ pass def __gt__(self, y): # real signature unknown; restored from __doc__ """ x.__gt__(y) <==> x>y """ pass def __init__(self, seq=None, **kwargs): # known special case of dict.__init__ """ dict() -> new empty dictionary dict(mapping) -> new dictionary initialized from a mapping object's (key, value) pairs dict(iterable) -> new dictionary initialized as if via: d = {} for k, v in iterable: d[k] = v dict(**kwargs) -> new dictionary initialized with the name=value pairs in the keyword argument list. For example: dict(one=1, two=2) # (copied from class doc) """ pass def __iter__(self): # real signature unknown; restored from __doc__ """ x.__iter__() <==> iter(x) """ pass def __len__(self): # real signature unknown; restored from __doc__ """ x.__len__() <==> len(x) """ pass def __le__(self, y): # real signature unknown; restored from __doc__ """ x.__le__(y) <==> x<=y """ pass def __lt__(self, y): # real signature unknown; restored from __doc__ """ x.__lt__(y) <==> x<y """ pass @staticmethod # known case of __new__ def __new__(S, *more): # real signature unknown; restored from __doc__ """ T.__new__(S, ...) -> a new object with type S, a subtype of T """ pass def __ne__(self, y): # real signature unknown; restored from __doc__ """ x.__ne__(y) <==> x!=y """ pass def __repr__(self): # real signature unknown; restored from __doc__ """ x.__repr__() <==> repr(x) """ pass def __setitem__(self, i, y): # real signature unknown; restored from __doc__ """ x.__setitem__(i, y) <==> x[i]=y """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ D.__sizeof__() -> size of D in memory, in bytes """ pass __hash__ = None dict
4、补充
dic = {'k1':'v1','k2':'v2','k3':'v3'} for key,value in dic.items(): #错误的方式 if key == 'k2': del dic[key] # RuntimeError: dictionary changed size during iteration print(dic.keys()) # 迭代器 # dict_keys(['k3', 'k2', 'k1']) for key in list(dic.keys()): if key == 'k2': del dic[key]
八、集合
如:{'lzl', 33, 'alex', 22, 'eric', 'wupeiqi', 11}
注:集合是一个无序的,不重复的数据组合。去重性,把一个列表变成集合,就自动去重了。关系测试,测试两组数据之前的交集、差集、并集
1、创建集合
#标准创建方式 info_set = set(["alex","wupeiqi","eric","lzl",11,22,33]) print(info_set,type(info_set)) #{33, 11, 'wupeiqi', 'lzl', 'alex', 'eric', 22} <class 'set'>
2、集合类常用功能
① 添加
#添加的两种方式 set_1 = set(["alex","wupeiqi","eric","lzl"]) set_1.add(11) #add只能添加一个元素 print(set_1) #{'alex', 'lzl', 'eric', 11, 'wupeiqi'} set_1 = set(["alex","wupeiqi","eric","lzl"]) set_1.update([11,22,33]) print(set_1) #update可以添加多个元素 #{33, 11, 'alex', 'wupeiqi', 'eric', 22, 'lzl'}
② 删除
#删除的三种方式 set_1 = set(["alex","wupeiqi","eric","lzl",11,22,33]) set_1.remove("alex") #remove 删除指定元素 print(set_1) #{'eric', 33, 'lzl', 11, 22, 'wupeiqi'} set_1.pop() #pop 随机删除元素 print(set_1) #{33, 'wupeiqi', 11, 22, 'lzl'} set_1.discard("lzl") #discard 删除指定元素,与remove区别在于,如果元素不存在也不会报错 set_1.discard(55) print(set_1) #{33, 'wupeiqi', 11, 22}
3、集合关系测试
① 交集
#交集 set_1 = set(["alex","wupeiqi","eric","lzl",11,22,33]) set_2 = set([11,22,33,44,55,66]) print(set_1.intersection(set_2)) #intersection 取两个set的交集 set_1和set_2可以互换位置 #{33, 11, 22} print(set_1.intersection(set_2,{22,11},{11})) #可写多个值 # {11}
② 并集
#并集 set_1 = set(["alex","wupeiqi","eric","lzl",11,22,33]) set_2 = set([11,22,33,44,55,66]) print(set_1.union(set_2)) #union 取两个set集合的并集 set_1和set_2可以互换位置 #{33, 66, 11, 44, 'eric', 55, 'lzl', 22, 'wupeiqi', 'alex'}
③ 差集
#差集 set_1 = set(["alex","wupeiqi","eric","lzl",11,22,33]) set_2 = set([11,22,33,44,55,66]) print(set_1.difference(set_2)) #difference 取两个set集合的差集 set_1有但是set_2没有的集合 #{'lzl', 'eric', 'wupeiqi', 'alex'}
④ 子集、父集
#子集 set_1 = set(["alex","wupeiqi","eric","lzl",11,22,33]) set_2 = set([11,22,33,44,55,66]) set_3 = set([11,22,33]) print(set_1.issubset(set_2)) #issubset 子集 #False print(set_1.issuperset(set_3)) #issuperset 父集 #True
⑤ 对称差集
#对称差集 set_1 = set(["alex","wupeiqi","eric","lzl",11,22,33]) set_2 = set([11,22,33,44,55,66]) print(set_1.symmetric_difference(set_2)) #symmetric_difference 对称差集=两个集合并集减去合集 #{66, 'lzl', 'eric', 'alex', 55, 'wupeiqi', 44}
⑥ 运算符做关系测试
#运算符做关系测试 set_1 = set(["alex","wupeiqi","eric","lzl",11,22,33]) set_2 = set([11,22,33,44,55,66]) set_union = set_1 | set_2 # 并集 set_intersection = set_1 & set_2 # 交集 set_difference = set_1 - set_2 # 差集 set_symmetric_difference = set_1 ^ set_2 # 对称差集
4、扩展
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
class set(object): """ set() -> new empty set object set(iterable) -> new set object Build an unordered collection of unique elements. """ def add(self, *args, **kwargs): # real signature unknown """ Add an element to a set. This has no effect if the element is already present. """ pass def clear(self, *args, **kwargs): # real signature unknown """ Remove all elements from this set. """ pass def copy(self, *args, **kwargs): # real signature unknown """ Return a shallow copy of a set. """ pass def difference(self, *args, **kwargs): # real signature unknown """ Return the difference of two or more sets as a new set. (i.e. all elements that are in this set but not the others.) """ pass def difference_update(self, *args, **kwargs): # real signature unknown """ Remove all elements of another set from this set. """ pass def discard(self, *args, **kwargs): # real signature unknown """ Remove an element from a set if it is a member. If the element is not a member, do nothing. """ pass def intersection(self, *args, **kwargs): # real signature unknown """ Return the intersection of two sets as a new set. (i.e. all elements that are in both sets.) """ pass def intersection_update(self, *args, **kwargs): # real signature unknown """ Update a set with the intersection of itself and another. """ pass def isdisjoint(self, *args, **kwargs): # real signature unknown """ Return True if two sets have a null intersection. """ pass def issubset(self, *args, **kwargs): # real signature unknown """ Report whether another set contains this set. """ pass def issuperset(self, *args, **kwargs): # real signature unknown """ Report whether this set contains another set. """ pass def pop(self, *args, **kwargs): # real signature unknown """ Remove and return an arbitrary set element. Raises KeyError if the set is empty. """ pass def remove(self, *args, **kwargs): # real signature unknown """ Remove an element from a set; it must be a member. If the element is not a member, raise a KeyError. """ pass def symmetric_difference(self, *args, **kwargs): # real signature unknown """ Return the symmetric difference of two sets as a new set. (i.e. all elements that are in exactly one of the sets.) """ pass def symmetric_difference_update(self, *args, **kwargs): # real signature unknown """ Update a set with the symmetric difference of itself and another. """ pass def union(self, *args, **kwargs): # real signature unknown """ Return the union of sets as a new set. (i.e. all elements that are in either set.) """ pass def update(self, *args, **kwargs): # real signature unknown """ Update a set with the union of itself and others. """ pass def __and__(self, *args, **kwargs): # real signature unknown """ Return self&value. """ pass def __contains__(self, y): # real signature unknown; restored from __doc__ """ x.__contains__(y) <==> y in x. """ pass def __eq__(self, *args, **kwargs): # real signature unknown """ Return self==value. """ pass def __getattribute__(self, *args, **kwargs): # real signature unknown """ Return getattr(self, name). """ pass def __ge__(self, *args, **kwargs): # real signature unknown """ Return self>=value. """ pass def __gt__(self, *args, **kwargs): # real signature unknown """ Return self>value. """ pass def __iand__(self, *args, **kwargs): # real signature unknown """ Return self&=value. """ pass def __init__(self, seq=()): # known special case of set.__init__ """ set() -> new empty set object set(iterable) -> new set object Build an unordered collection of unique elements. # (copied from class doc) """ pass def __ior__(self, *args, **kwargs): # real signature unknown """ Return self|=value. """ pass def __isub__(self, *args, **kwargs): # real signature unknown """ Return self-=value. """ pass def __iter__(self, *args, **kwargs): # real signature unknown """ Implement iter(self). """ pass def __ixor__(self, *args, **kwargs): # real signature unknown """ Return self^=value. """ pass def __len__(self, *args, **kwargs): # real signature unknown """ Return len(self). """ pass def __le__(self, *args, **kwargs): # real signature unknown """ Return self<=value. """ pass def __lt__(self, *args, **kwargs): # real signature unknown """ Return self<value. """ pass @staticmethod # known case of __new__ def __new__(*args, **kwargs): # real signature unknown """ Create and return a new object. See help(type) for accurate signature. """ pass def __ne__(self, *args, **kwargs): # real signature unknown """ Return self!=value. """ pass def __or__(self, *args, **kwargs): # real signature unknown """ Return self|value. """ pass def __rand__(self, *args, **kwargs): # real signature unknown """ Return value&self. """ pass def __reduce__(self, *args, **kwargs): # real signature unknown """ Return state information for pickling. """ pass def __repr__(self, *args, **kwargs): # real signature unknown """ Return repr(self). """ pass def __ror__(self, *args, **kwargs): # real signature unknown """ Return value|self. """ pass def __rsub__(self, *args, **kwargs): # real signature unknown """ Return value-self. """ pass def __rxor__(self, *args, **kwargs): # real signature unknown """ Return value^self. """ pass def __sizeof__(self): # real signature unknown; restored from __doc__ """ S.__sizeof__() -> size of S in memory, in bytes """ pass def __sub__(self, *args, **kwargs): # real signature unknown """ Return self-value. """ pass def __xor__(self, *args, **kwargs): # real signature unknown """ Return self^value. """ pass __hash__ = None
九、程序练习
写一个购物程序要求:
① 有商家模式和用户模式
② 商家模式下可以对商品价格修改,增加新的商品
③ 用户购买信息会被保存,下次继承上次购物信息
商品文件:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
iPhone 5299 iWatch 2999 MacBook 9999 iPad 3999 Bicycle 999 X-box 4199 Letv 3019 Book 99
Readme:
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
# 这是一个模拟商城购物的程序 ### 作者介绍: * author:lzl ### 博客地址: * http://www.cnblogs.com/lianzhilei/p/5722771.html * http://www.cnblogs.com/lianzhilei/p/5724847.html * http://www.cnblogs.com/lianzhilei/p/5725172.html ### 实现效果: * product_information文件记录了可用于购买的商品信息 * 商家模式可以对商品的价格修改,上架新的商品,并把商品信息新增到Product_informationw文件中 * 用户模式第一次登录,输入购物金额,把购物信息和余额分别写入user_cash_information和user_shop_information * 用户模式第二次登录,继承上次购物商品和余额 * 详细功能参照流程图 ### 运行环境: * Python3.0+ 最佳Python3.5.2 ### 目录结构: Day2 ├── 购物车 │ ├── shopping.py │ └── product_information │ ├── user_cash_information │ ├── user_shop_interface.png │ └── readme ### linux 运行说明: * 上述文件都拷贝到同一级目录下 * 加执行权限 chmod 755 shopping.py * 执行程序 python shopping.py
流程图:
![](https://images2015.cnblogs.com/blog/997909/201608/997909-20160803210325387-1720671315.png)
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
#!/usr/bin/env python # -*- coding:utf-8 -*- #-Author-Lian Pro_inf = open("product_information","r") #读取文件product_information里的内容 Pro_list = [] #定义空列表Pro_list,后面商品信息打印添加都在此列表 Shopping_list = [] #定义空列表Shopping_list,用于已购商品的添加和打印 for item in Pro_inf.readlines(): Pro_list.append(item.strip("\n").split()) #把product_information里的内容以列表的形式添加到Pro_list Pro_inf.close() def Print_pro_inf(): #定义变量Print_pro_inf()为 实时打印在售商品数量和价格信息 print("编号\t商品\t\t价格") for index, item in enumerate(Pro_list): print("%s\t\t%s\t\t%s"%(index, item[0], item[1])) def Error_prompt_number(): #定义错误提示信息 print("\33[31;1m错误:没有相应的编号 请重新输入:\33[0m\n") while True: Iden_chocie = input("编号\t模式\n1\t\t商家\n2\t\t用户\n\33[34;0m请选择相应的编号 进入商家模式还是用户模式:【1/2】\33[0m") if Iden_chocie == "1": #判断选择的是否为商家模式 print(("你现在进入的商家模式").center(50, "*"), "\n") while True: print("目前商城在售的商品信息".center(40, "-")) Print_pro_inf() #打印当前的商城信息 Business_choice = input("\33[34;0m选择接下来要对商城进行的操作 【上新 Y】/【改价 E】/【退出 Q】\33[0m:") if Business_choice == "Y" or Business_choice == "y": #判断商家是否要上新 while True: Pro_new = input("\33[34;0m请输入要新加商品的名称:\33[0m") Pri_new = input("\33[34;0m请输入新加商品 %s 的价格:\33[0m"%(Pro_new)) if Pri_new.isdigit(): #判断新加商品是否为整数 If_save = input("是否加入\33[31;1m新商品:%s\t价格:%s\33[0m 到商城 \33[34;0m【确定 Y】/【否 N】\33[0m"%(Pro_new,Pri_new)) if If_save == "Y" or If_save == "y": #判断对之前的操作是否保存 Pro_inf = open("product_information", "a") #打开文件product_information,追加模式 Pro_inf.write("%s\t%s\n"%(Pro_new,Pri_new)) #新上架的商品、价格写入到product_information文件 Pro_inf.close() Pro_list.append([Pro_new,Pri_new]) #新上架的商品、价格添加到列表Pro_list print("\33[31;1m商品:%s上新到商城成功!\33[0m "%(Pro_new)) break elif If_save == "N" or If_save == "n": #不保存当前上架的商品到商城 print("\33[31;1m上新失败!\33[0m") break else: #格式输入错误提示 print("\33[31;1m错误:没有相应的选项\33[0m") else: #格式输入错误提示 print("\33[31;1m错误:输入的价格格式错误\33[0m\n") elif Business_choice == "E" or Business_choice == "e": #判断商家是否要对商品价格进行修改 while True: Pri_edit = input("选择要修改价格的商品编号 :") if Pri_edit.isdigit(): #判断输入的编码是否为整数 Pri_edit = int(Pri_edit) #转换为int if Pri_edit < len(Pro_list) and Pri_edit >= 0: #判断输入的编码是否存在 Pri_edit_item = Pro_list[Pri_edit] Pri_edit_new = input("请输入要修改后的价格 :") if Pri_edit_new.isdigit(): #判断要修改后的价格是否为整数 Pri_edit_new = int(Pri_edit_new) If_save = input("\33[31;1m编号:%s 商品:%s 原价:%s 价格修改为:%s\33[0m \33[34;0m【确定 Y】/【否 N】\33[0m"% (Pri_edit,Pri_edit_item[0],Pri_edit_item[1],Pri_edit_new)) if If_save == "Y" or If_save == "y": #确定是否要对商品的价格进行修改 print("\33[31;1m价格修改成功!\33[0m") Pri_edit_item[1] = Pri_edit_new Pro_inf = open("product_information", "w") #把文件product_information商品信息清空 Pro_inf.close() Pro_inf = open("product_information", "a") #对文件product_information进行追加操作 for item in Pro_list: #把最新的商品信息写入到文件product_information中 Pro_inf.write(item[0]) Pro_inf.write("\t") Pro_inf.write(str(item[1])) Pro_inf.write("\n") Pro_inf.close() break elif If_save == "N" or If_save == "n": #确定是否不保存刚才修改的价格信息 print("\33[31;1m价格修改失败!\33[0m") break else: #输入的字符格式错误提示 print("\33[31;1m错误:没有相应的选项 \33[0m") else: #价格输入格式错误提示 print("\33[31;1m错误:输入的价格格式错误\33[0m\n") else: #输入的字符格式错误提示 Error_prompt_number() else: #输入的字符格式错误提示 Error_prompt_number() elif Business_choice == "Q" or Business_choice == "q": #退出程序 print("退出商家用户".center(40, "-")) exit() else: print("\33[31;1m错误:没有相应的选项 \33[0m") elif Iden_chocie == "2": #判断选择的是否为购物模式 User_cash_read = open("user_cash_information","r") #读取文件user_cash_information信息 User_cash_read_line =User_cash_read.readlines() #读取到的文件转换为list if len(User_cash_read_line) == 0: #判断字符长度是否为0 如果为空用户为第一次登录 print("\33[31;0m欢迎第一次来购物\33[0m".center(40, "-")) while True: User_cash = input("\33[34;0m请输入用于购物的金额:\33[0m") if User_cash.isdigit(): #如果输入的金额为整数,转换为int User_cash = int(User_cash) break else: #输入的金额不为整数,报错提示 print("\33[31;0m购物的金额输入错误\33[0m") else: #如果User_cash_read_line字符长度不为空,用户非第一次登录 User_cash = int(User_cash_read_line[0]) #继承之前购物余额 User_shop_read= open("user_shop_information", "r") #读取user_shop_information文件,打印之前已购商品清单 User_shop_read.line = User_shop_read.readlines() print("\33[31;0m之前已经购买的商品".center(30,"-")) for item in User_shop_read.line: print(item.strip("\n")) print("你的当前余额:%s\33[0m"%(User_cash)) User_cash_read.close() #关掉文件 User_shop_read.close() print(("你现在进入的用户购物模式").center(50, "*"),"\n") while True: print(("目前商城在售的商品信息").center(40, "-")) Print_pro_inf() #打印在售商品信息 Num_usr_choice = input("\33[34;0m选择要购买的商品编号 【购买 ID】/【退出 Q】\33[0m:") if Num_usr_choice.isdigit(): #判断输入的编号是否为整数 Num_usr_choice = int(Num_usr_choice) #转换为int if Num_usr_choice < len(Pro_list) and Num_usr_choice >=0: #判断输入的商品编号是否存在 pro_item = Pro_list[Num_usr_choice] if int(pro_item[1]) <= User_cash: #判断当前的余额是否可以购买 User_cash -= int(pro_item[1]) #余额减去购买的商品价格 Shopping_list.append(pro_item) #商品加入已购商品清单里 print("\33[31;1m已经购买了商品:%s 当前余额为%s\33[0m"%(pro_item[0],User_cash)) print("\33[31;0m目前已经购买了\33[0m".center(40,"-")) for item in Shopping_list: #打印当前已购商品列表 print("\33[31;0m%s\t%s\33[0m"%(item[0],item[1])) else: #当前余额不足以购买 print("\33[31;1m提示:余额不足 当前余额:%s\33[0m"%(User_cash)) else: #输入的编号不存在 Error_prompt_number() elif Num_usr_choice == "Q" or Num_usr_choice == "q": #是否结束购物,退出程序 print("退出购物用户".center(40, "-")) User_cash_write = open("user_cash_information", "w") #清空user_cash_information文件记录的余额信息 User_cash_write.write(str(User_cash)) #把最新的余额信息写入user_cash_information文件 User_cash_write.close() User_shop_write = open("user_shop_information", "a") #打开user_shop_information文件,追加模式 for item in Shopping_list: #把已购商品信息追加写入到user_shop_information文件中 User_shop_write.write(item[0]) User_shop_write.write("\t") User_shop_write.write(str(item[1])) User_shop_write.write("\n") User_shop_write.close() exit() else: #输入的字符格式错误提示 Error_prompt_number() else: #输入的字符格式错误提示 Error_prompt_number()