python 基础之字符串方法

字符串

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1	print('chenxi'*8)

　　测试

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D:\python\python.exe D:/untitled/dir/for.py chenxichenxichenxichenxichenxichenxichenxichenxi   Process finished with exit code 0

　　字符串切片打印处理

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1	print('chenxi'[2:])

　　测试

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1 2	D:\python\python.exe D:/untitled/dir/for.py enxi

　　判断字符串里有没有包含对应得字符

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1 2	print('x'in 'chenxi') print('f'in 'chenxi')

　　测试

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1 2	True False

　　字符串拼接，不建议使用这种方法

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a='cx' b='zrd' c=a+b print(c)

　　测试

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D:\python\python.exe D:/untitled/dir/for.py cxzrd   Process finished with exit code 0

　　字符串拼接

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a='cx' b='zrd' c=''.join([a,b]) print(c)

　　测试

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D:\python\python.exe D:/untitled/dir/for.py cxzrd   Process finished with exit code 0

　　字符串拼接

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a='cx' b='zrd' bb='haha' c='-----'.join([a,b,bb]) print(c)

　　测试

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1 2	D:\python\python.exe D:/untitled/dir/for.py cx-----zrd-----haha

　　字符串之统计关键字个数

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1 2	dis = 'hebei tianjing guanzhou' print(dis.count('i'))

　　测试

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1 2	D:\python\python.exe D:/untitled/dir/for.py 3

　　字符串之修改首字母为大写

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1 2	dis = 'hebei tianjing guanzhou' print(dis.capitalize())

　　测试

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1 2	D:\python\python.exe D:/untitled/dir/for.py Hebei tianjing guanzhou

　　一共打印50字符，不够用指定字符去补，原先字符串内容居中

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1 2	dis = 'hebei tianjing guanzhou' print(dis.center(50,'#'))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py #############hebei tianjing guanzhou##############   Process finished with exit code 0

　　判断字符串是不是以什么结尾的

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dis = 'hebei tianjing guanzhou' print(dis.endswith('u')) print(dis.endswith('i'))

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D:\python\python.exe D:/untitled/dir/for.py True False   Process finished with exit code 0

　　判断字符串是不是以什么开头的

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1 2	dis = 'hebei tianjing guanzhou' print(dis.startswith('he'))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py True   Process finished with exit code 0

　　修改字符串里tab的默认空格数量\t 表示tab键

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1 2	dis = 'he\tbei tianjing guanzhou' print(dis.expandtabs(tabsize=10))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py he        bei tianjing guanzhou   Process finished with exit code 0

　　找到字符串里第一个元素定返回索引值

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1 2	dis = 'hebei tianjing guanzhou' print(dis.find('a'))

　　测试

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1 2	D:\python\python.exe D:/untitled/dir/for.py 8

　　将字符串变量赋值打印

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1 2	dis = 'hebei tianjing guanzhou {name}' print(dis.format(name='zrd'))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py hebei tianjing guanzhou zrd   Process finished with exit code 0

　　以字典方式批量给字符串赋值

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1 2	dis = 'hebei tianjing guanzhou {name} ll {age}' print(dis.format_map({'name':'zrd','age':22}))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py hebei tianjing guanzhou zrd ll 22   Process finished with exit code 0

　　查字符串里关键字并返回索引值，字符串里没有关键字报错

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dis = 'hebei tianjing guanzhou {name} ll {age}' print(dis.index('i')) print(dis.index('d'))

　测试

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D:\python\python.exe D:/untitled/dir/for.py Traceback (most recent call last):   File "D:/untitled/dir/for.py", line 170, in <module>     print(dis.index('d')) ValueError: substring not found 4

　　判断字符串是否包含特殊字符

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print('test564'.isalnum() ) print('tygc*'.isalnum()) print('reswd'.isalnum()) print('7890'.isalnum()) print('宋氏家族'.isalnum())

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D:\python\python.exe D:/untitled/dir/for.py True False True True True

　　判断字符串像不像十进制的数字

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print("3455".isdecimal()) print("程序".isdecimal()) print("AF09".isdecimal()) print("hevb".isdecimal())

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D:\python\python.exe D:/untitled/dir/for.py True False False False

　　判断字符串是否包含一个非法字符

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1 2	print("dtfghvh".isidentifier()) print("1233tyghgvh".isidentifier())  #非法字符

　　测试

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D:\python\python.exe D:/untitled/dir/for.py True False

　　判断字符是不是空格

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1	print(' '.isspace())

　　测试

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D:\python\python.exe D:/untitled/dir/for.py True   Process finished with exit code 0

　　判断字符串是不是标题格式

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1 2	print('My Ch'.istitle()) print('My ch'.istitle())

　　测试

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1 2	True False

　　字符串里所有大写改成小写

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1	print('My Ch'.lower())

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D:\python\python.exe D:/untitled/dir/for.py my ch   Process finished with exit code 0

　　字符串所有小写该大写

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1	print('My Ch'.upper())

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D:\python\python.exe D:/untitled/dir/for.py MY CH   Process finished with exit code 0

　　字符串中大小写翻转

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1	print('My Ch'.swapcase())

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D:\python\python.exe D:/untitled/dir/for.py mY cH   Process finished with exit code 0

　　在字符串后面以特定字符补够特定数量

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1	print('My Ch'.ljust(50，'*'))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py My Ch*********************************************   Process finished with exit code 0

　　在字符串前面以特定字符补够特定数量

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1	print('My Ch'.rjust(50,'*'))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py *********************************************My Ch   Process finished with exit code 0

　　将字符串前后空格去掉

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1	print('       My Ch'.strip())

　　测试

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D:\python\python.exe D:/untitled/dir/for.py My Ch   Process finished with exit code 0

　　字符串内容替换

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1	print('chenxi ffff'.replace('ffff','zrd'))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py chenxi zrd   Process finished with exit code 0

　　字符串内容替换的次数控制

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print('chenxi ffff'.replace('ffff','zrd')) print('chenxi ffff  tygdf'.replace('ff','zrd')) print('chenxi ffff  tygdf'.replace('ffff','zrd',1))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py chenxi zrd chenxi zrdzrd  tygdf chenxi zrd  tygdf   Process finished with exit code 0

　　查字符串最后一个关键字在第几个索引

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1	print('chenxi cx xlc'.rfind('x'))

　测试

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D:\python\python.exe D:/untitled/dir/for.py 10   Process finished with exit code 0

　　将字符串以空格为分隔符，分成列表

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1	print('chenxi cx xlc'.split(' '))

　　测试

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D:\python\python.exe D:/untitled/dir/for.py ['chenxi', 'cx', 'xlc']   Process finished with exit code 0