模块

一、sys

二、os

三、hashlib

四、random

五、re

六、pickle,json

七、configparser

八、XML

九、requests

十、logging              alex

十一、系统命令

十二、shutil

十三、paramiko 

十四、time

 

 

 

模块,用一砣代码实现了某个功能的代码集合。 

类似于函数式编程和面向过程编程,函数式编程则完成一个功能,其他代码用来调用即可,提供了代码的重用性和代码间的耦合。而对于一个复杂的功能来,可能需要多个函数才能完成(函数又可以在不同的.py文件中),n个 .py 文件组成的代码集合就称为模块。

如:os 是系统相关的模块;file是文件操作相关的模块

模块分为三种:

  • 自定义模块
  • 开源模块
  • 内置标准模块(又称标准库)

自定义模块                                               

1.定义模块

.py文件

2.导入模块

 1 #导入模块有一下几种方法:
 2 import module
 3 from module.xx.xx import xx
 4 from module.xx.xx import xx as rename  
 5 from module.xx.xx import *
 6 
 7 
 8 #导入模块其实就是告诉Python解释器去解释那个py文件
 9 ##导入一个py文件,解释器解释该py文件
10 ##导入一个包,解释器解释该包下的 __init__.py 文件 【py2.7】
11 
12 #那么问题来了,导入模块时是根据那个路径作为基准来进行的呢?即:sys.path
13 import sys
14 print(sys.path)
15 
16 #如果sys.path路径列表没有你想要的路径,可以通过 sys.path.append('路径') 添加。
17 import sys
18 import os
19 project_path = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))  #相对路径
20 sys.path.append(project_path)
View Code

 

内置模块                                                    

内置模块是Python自带的功能,在使用内置模块相应的功能时,需要【先导入】再【使用】

一、sys

用于提供对Python解释器相关的操作:

1 sys.argv           命令行参数List,第一个元素是程序本身路径
2 sys.exit(n)        退出程序,正常退出时exit(0)
3 sys.version        获取Python解释程序的版本信息
4 sys.maxint         最大的Int值
5 sys.path           返回模块的搜索路径,初始化时使用PYTHONPATH环境变量的值
6 sys.platform       返回操作系统平台名称
7 sys.stdin          输入相关
8 sys.stdout         输出相关
9 sys.stderror       错误相关x
View Code

 

 1 import sys
 2 import time
 3 
 4 
 5 def view_bar(num, total):
 6     #显示百分比
 7     rate = float(num) / float(total)
 8     rate_num = int(rate * 100)
 9     r = '\r%d%%' % (rate_num, )
10     sys.stdout.write(r)
11     sys.stdout.flush()
12 
13 
14 if __name__ == '__main__':
15     for i in range(0, 100):
16         time.sleep(0.1)
17         view_bar(i, 100)
进度百分比

 

二、os

 用于提供系统级别的操作:

 1 os.getcwd()                 获取当前工作目录,即当前python脚本工作的目录路径
 2 os.chdir("dirname")         改变当前脚本工作目录;相当于shell下cd
 3 os.curdir                   返回当前目录: ('.')
 4 os.pardir                   获取当前目录的父目录字符串名:('..')
 5 os.makedirs('dir1/dir2')    可生成多层递归目录
 6 os.removedirs('dirname1')   若目录为空,则删除,并递归到上一级目录,如若也为空,则删除,依此类推
 7 os.mkdir('dirname')         生成单级目录;相当于shell中mkdir dirname
 8 os.rmdir('dirname')         删除单级空目录,若目录不为空则无法删除,报错;相当于shell中rmdir dirname
 9 os.listdir('dirname')       列出指定目录下的所有文件和子目录,包括隐藏文件,并以列表方式打印
10 os.remove()                 删除一个文件
11 os.rename("oldname","new")  重命名文件/目录
12 os.stat('path/filename')    获取文件/目录信息
13 os.sep                      操作系统特定的路径分隔符,win下为"\\",Linux下为"/"
14 os.linesep                  当前平台使用的行终止符,win下为"\t\n",Linux下为"\n"
15 os.pathsep                  用于分割文件路径的字符串
16 os.name                     字符串指示当前使用平台。win->'nt'; Linux->'posix'
17 os.system("bash command")   运行shell命令,直接显示
18 os.environ                  获取系统环境变量
19 os.path.abspath(path)       返回path规范化的绝对路径
20 os.path.split(path)         将path分割成目录和文件名二元组返回
21 os.path.dirname(path)       返回path的目录。其实就是os.path.split(path)的第一个元素
22 os.path.basename(path)      返回path最后的文件名。如何path以/或\结尾,那么就会返回空值。即os.path.split(path)的第二个元素
23 os.path.exists(path)        如果path存在,返回True;如果path不存在,返回False
24 os.path.isabs(path)         如果path是绝对路径,返回True
25 os.path.isfile(path)        如果path是一个存在的文件,返回True。否则返回False
26 os.path.isdir(path)         如果path是一个存在的目录,则返回True。否则返回False
27 os.path.join(path1[, path2[, ...]])  将多个路径组合后返回,第一个绝对路径之前的参数将被忽略
28 os.path.getatime(path)      返回path所指向的文件或者目录的最后存取时间
29 os.path.getmtime(path)      返回path所指向的文件或者目录的最后修改时间
View Code

 

三、hashlib

用于加密相关的操作,代替了md5模块和sha模块,主要提供 SHA1, SHA224, SHA256, SHA384, SHA512 ,MD5 算法

 1 import hashlib
 2  
 3 # ######## md5 ########
 4 hash = hashlib.md5()
 5 # help(hash.update)
 6 hash.update(bytes('admin', encoding='utf-8'))
 7 print(hash.hexdigest())
 8 print(hash.digest())
 9  
10  
11 ######## sha1 ########
12  
13 hash = hashlib.sha1()
14 hash.update(bytes('admin', encoding='utf-8'))
15 print(hash.hexdigest())
16  
17 # ######## sha256 ########
18  
19 hash = hashlib.sha256()
20 hash.update(bytes('admin', encoding='utf-8'))
21 print(hash.hexdigest())
22  
23  
24 # ######## sha384 ########
25  
26 hash = hashlib.sha384()
27 hash.update(bytes('admin', encoding='utf-8'))
28 print(hash.hexdigest())
29  
30 # ######## sha512 ########
31  
32 hash = hashlib.sha512()
33 hash.update(bytes('admin', encoding='utf-8'))
34 print(hash.hexdigest())
View Code
 1 #以上加密算法虽然依然非常厉害,但时候存在缺陷,即:通过撞库可以反解。所以,有必要对加密算法中添加自定义key再来做加密。
 2 import hashlib
 3  
 4 # ######## md5 ########
 5  
 6 hash = hashlib.md5(bytes('898oaFs09f',encoding="utf-8"))
 7 hash.update(bytes('admin',encoding="utf-8"))
 8 print(hash.hexdigest())
 9 
10 
11 
12 #python内置还有一个 hmac 模块,它内部对我们创建 key 和 内容 进行进一步的处理然后再加密
13 import hmac
14  
15 h = hmac.new(bytes('898oaFs09f',encoding="utf-8"))
16 h.update(bytes('admin',encoding="utf-8"))
17 print(h.hexdigest())
key加密

 四、random

1 import random
2  
3 print(random.random())
4 print(random.randint(1, 2))
5 print(random.randrange(1, 10))
 1 import random
 2 checkcode = ''
 3 for i in range(4):
 4     current = random.randrange(0,4)
 5     if current != i:
 6         temp = chr(random.randint(65,90))
 7     else:
 8         temp = random.randint(0,9)
 9     checkcode += str(temp)
10 print checkcode
11 
12 # 随机验证码
随机验证

五、re

python中re模块提供了正则表达式相关操作

规则

match  从起始位置开始匹配,匹配成功返回一个对象,未匹配成功返回None

 1  #match(pattern, string, flags=0)
 2  # pattern: 正则模型
 3  # string : 要匹配的字符串
 4  # falgs  : 匹配模式
 5      X  VERBOSE     Ignore whitespace and comments for nicer looking RE's.
 6      I  IGNORECASE  Perform case-insensitive matching.
 7      M  MULTILINE   "^" matches the beginning of lines (after a newline)
 8                     as well as the string.
 9                     "$" matches the end of lines (before a newline) as well
10                     as the end of the string.
11      S  DOTALL      "." matches any character at all, including the newline.
12  
13      A  ASCII       For string patterns, make \w, \W, \b, \B, \d, \D
14                     match the corresponding ASCII character categories
15                     (rather than the whole Unicode categories, which is the
16                     default).
17                     For bytes patterns, this flag is the only available
18                     behaviour and needn't be specified.
19       
20      L  LOCALE      Make \w, \W, \b, \B, dependent on the current locale.
21      U  UNICODE     For compatibility only. Ignored for string patterns (it
22                     is the default), and forbidden for bytes patterns.
View Code
 1  # 无分组
 2         r = re.match("h\w+", origin)
 3         print(r.group())     # 获取匹配到的所有结果
 4         print(r.groups())    # 获取模型中匹配到的分组结果
 5         print(r.groupdict()) # 获取模型中匹配到的分组结果
 6 
 7         # 有分组
 8 
 9         # 为何要有分组?提取匹配成功的指定内容(先匹配成功全部正则,再匹配成功的局部内容提取出来)
10 
11         r = re.match("h(\w+).*(?P<name>\d)$", origin)
12         print(r.group())     # 获取匹配到的所有结果
13         print(r.groups())    # 获取模型中匹配到的分组结果
14         print(r.groupdict()) # 获取模型中匹配到的分组中所有执行了key的组
Demo

search 浏览整个字符串去匹配第一个,未匹配成功返回None

search(pattern, string, flags=0)

 

# 无分组

        r = re.search("a\w+", origin)
        print(r.group())     # 获取匹配到的所有结果
        print(r.groups())    # 获取模型中匹配到的分组结果
        print(r.groupdict()) # 获取模型中匹配到的分组结果

        # 有分组

        r = re.search("a(\w+).*(?P<name>\d)$", origin)
        print(r.group())     # 获取匹配到的所有结果
        print(r.groups())    # 获取模型中匹配到的分组结果
        print(r.groupdict()) # 获取模型中匹配到的分组中所有执行了key的组
demo

 

findall,获取非重复的匹配列表

如果有一个组则以列表形式返回,且每一个匹配均是字符串;如果模型中有多个组,则以列表形式返回,且每一个匹配均是元祖;空的匹配也会包含在结果中
#findall(pattern, string, flags=0)
 
# 无分组
        r = re.findall("a\w+",origin)
        print(r)

        # 有分组
        origin = "hello alex bcd abcd lge acd 19"
        r = re.findall("a((\w*)c)(d)", origin)
        print(r)
Demo

 

sub,替换匹配成功的指定位置字符串
sub(pattern, repl, string, count=0, flags=0)
# pattern: 正则模型
# repl   : 要替换的字符串或可执行对象
# string : 要匹配的字符串
# count  : 指定匹配个数
# flags  : 匹配模式

  

Demo
1 # 与分组无关
2 
3         origin = "hello alex bcd alex lge alex acd 19"
4         r = re.sub("a\w+", "999", origin, 2)
5         print(r)

split,根据正则匹配分割字符串

split(pattern, string, maxsplit=0, flags=0)
# pattern: 正则模型
# string : 要匹配的字符串
# maxsplit:指定分割个数
# flags  : 匹配模式

 

# 无分组
        origin = "hello alex bcd alex lge alex acd 19"
        r = re.split("alex", origin, 1)
        print(r)

        # 有分组
        
        origin = "hello alex bcd alex lge alex acd 19"
        r1 = re.split("(alex)", origin, 1)
        print(r1)
        r2 = re.split("(al(ex))", origin, 1)
        print(r2)
Demo
IP:
^(25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}$
手机号:
^1[3|4|5|8][0-9]\d{8}$
邮箱:
[a-zA-Z0-9_-]+@[a-zA-Z0-9_-]+(\.[a-zA-Z0-9_-]+)+
常用正则表达式

 

六、序列化

Python中用于序列化的两个模块

  • json     用于【字符串】和 【python基本数据类型】 间进行转换
  • pickle   用于【python特有的类型】 和 【python基本数据类型】间进行转换

Json模块提供了四个功能:dumps、dump、loads、load(序、序写、解、读解)

pickle模块提供了四个功能:dumps、dump、loads、load

 1 # 序列化
 2 
 3 import pickle
 4 user_={
 5 "ming":124,
 6 "xuan":345,
 7 "wang":4546,
 8 }
 9 
10 # 序列化
11 with open("读写.txt","wb") as f:
12     f.write(pickle.dumps(user_))
13 
14 #序列化,写入
15 with open("读写.txt","wb") as f:
16     pickle.dump(user_,f)
17 
18 #序列化
19 with open("读写.txt","rb") as f:
20     users = pickle.loads(f.read())
21     print(users)
22 
23 #序列化,读取
24 with open("读写.txt","rb") as f:   
25     users =pickle.load(f)
26 print(users)
View Code

 

七. configparser

configparser用于处理特定格式的文件,其本质上是利用open来操作文件。(2.x版本为ConfigParser)

# 注释1
;  注释2
 
[section1] # 节点
k1 = v1    #
k2:v2       #
 
[section2] # 节点
k1 = v1    #
特定格式

 

 1 import configparser
 2  
 3 config = configparser.ConfigParser()
 4 config.read('xxxooo', encoding='utf-8')
 5 
 6 #1、获取、节点、键、值
 7 #所有节点
 8 ret = config.sections()
 9 print(ret)
10 
11 #指定节点下所有的键值对
12 ret = config.items('section1')
13 print(reth)
14 
15 #指定节点下所有的建
16 ret = config.options('section1')
17 print(ret)
18 
19 #指定节点下指定key的值
20 v = config.get('section1', 'k1')
21 # v = config.getint('section1', 'k1')
22 # v = config.getfloat('section1', 'k1')
23 # v = config.getboolean('section1', 'k1')
24 
25 #2、检查、删除、添加节点
26 # 检查
27 has_sec = config.has_section('section1')
28 print(has_sec)
29  
30 # 添加节点
31 config.add_section("SEC_1")
32 config.write(open('xxxooo', 'w'))
33  
34 # 删除节点
35 config.remove_section("SEC_1")
36 config.write(open('xxxooo', 'w'))
37 
38 #3、检查、删除、设置指定组内的键值对
39 # 检查
40 has_opt = config.has_option('section1', 'k1')
41 print(has_opt)
42  
43 # 删除
44 config.remove_option('section1', 'k1')
45 config.write(open('xxxooo', 'w'))
46  
47 # 设置
48 config.set('section1', 'k10', "123")
49 config.write(open('xxxooo', 'w'))
View Code

八、XML       pass

XML是实现不同语言或程序之间进行数据交换的协议,XML文件格式如下:

<data>
    <country name="Liechtenstein">
        <rank updated="yes">2</rank>
        <year>2023</year>
        <gdppc>141100</gdppc>
        <neighbor direction="E" name="Austria" />
        <neighbor direction="W" name="Switzerland" />
    </country>
    <country name="Singapore">
        <rank updated="yes">5</rank>
        <year>2026</year>
        <gdppc>59900</gdppc>
        <neighbor direction="N" name="Malaysia" />
    </country>
    <country name="Panama">
        <rank updated="yes">69</rank>
        <year>2026</year>
        <gdppc>13600</gdppc>
        <neighbor direction="W" name="Costa Rica" />
        <neighbor direction="E" name="Colombia" />
    </country>
</data>
xml文件

 

 1 #利用ElementTree.parse将文件直接解析成xml对象
 2 
 3 from xml.etree import ElementTree as ET
 4 # 直接解析xml文件
 5 tree = ET.parse("xo.xml")
 6 # 获取xml文件的根节点
 7 root = tree.getroot()
 8 
 9 
10 #利用ElementTree.parse将文件直接解析成xml对象
11 
12 from xml.etree import ElementTree as ET
13 # 直接解析xml文件
14 tree = ET.parse("xo.xml")
15 # 获取xml文件的根节点
16 root = tree.getroot()
View Code

2、操作XML

XML格式类型是节点嵌套节点,对于每一个节点均有以下功能,以便对当前节点进行操作:

  1 class Element:
  2     """An XML element.
  3 
  4     This class is the reference implementation of the Element interface.
  5 
  6     An element's length is its number of subelements.  That means if you
  7     want to check if an element is truly empty, you should check BOTH
  8     its length AND its text attribute.
  9 
 10     The element tag, attribute names, and attribute values can be either
 11     bytes or strings.
 12 
 13     *tag* is the element name.  *attrib* is an optional dictionary containing
 14     element attributes. *extra* are additional element attributes given as
 15     keyword arguments.
 16 
 17     Example form:
 18         <tag attrib>text<child/>...</tag>tail
 19 
 20     """
 21 
 22     当前节点的标签名
 23     tag = None
 24     """The element's name."""
 25 
 26     当前节点的属性
 27 
 28     attrib = None
 29     """Dictionary of the element's attributes."""
 30 
 31     当前节点的内容
 32     text = None
 33     """
 34     Text before first subelement. This is either a string or the value None.
 35     Note that if there is no text, this attribute may be either
 36     None or the empty string, depending on the parser.
 37 
 38     """
 39 
 40     tail = None
 41     """
 42     Text after this element's end tag, but before the next sibling element's
 43     start tag.  This is either a string or the value None.  Note that if there
 44     was no text, this attribute may be either None or an empty string,
 45     depending on the parser.
 46 
 47     """
 48 
 49     def __init__(self, tag, attrib={}, **extra):
 50         if not isinstance(attrib, dict):
 51             raise TypeError("attrib must be dict, not %s" % (
 52                 attrib.__class__.__name__,))
 53         attrib = attrib.copy()
 54         attrib.update(extra)
 55         self.tag = tag
 56         self.attrib = attrib
 57         self._children = []
 58 
 59     def __repr__(self):
 60         return "<%s %r at %#x>" % (self.__class__.__name__, self.tag, id(self))
 61 
 62     def makeelement(self, tag, attrib):
 63         创建一个新节点
 64         """Create a new element with the same type.
 65 
 66         *tag* is a string containing the element name.
 67         *attrib* is a dictionary containing the element attributes.
 68 
 69         Do not call this method, use the SubElement factory function instead.
 70 
 71         """
 72         return self.__class__(tag, attrib)
 73 
 74     def copy(self):
 75         """Return copy of current element.
 76 
 77         This creates a shallow copy. Subelements will be shared with the
 78         original tree.
 79 
 80         """
 81         elem = self.makeelement(self.tag, self.attrib)
 82         elem.text = self.text
 83         elem.tail = self.tail
 84         elem[:] = self
 85         return elem
 86 
 87     def __len__(self):
 88         return len(self._children)
 89 
 90     def __bool__(self):
 91         warnings.warn(
 92             "The behavior of this method will change in future versions.  "
 93             "Use specific 'len(elem)' or 'elem is not None' test instead.",
 94             FutureWarning, stacklevel=2
 95             )
 96         return len(self._children) != 0 # emulate old behaviour, for now
 97 
 98     def __getitem__(self, index):
 99         return self._children[index]
100 
101     def __setitem__(self, index, element):
102         # if isinstance(index, slice):
103         #     for elt in element:
104         #         assert iselement(elt)
105         # else:
106         #     assert iselement(element)
107         self._children[index] = element
108 
109     def __delitem__(self, index):
110         del self._children[index]
111 
112     def append(self, subelement):
113         为当前节点追加一个子节点
114         """Add *subelement* to the end of this element.
115 
116         The new element will appear in document order after the last existing
117         subelement (or directly after the text, if it's the first subelement),
118         but before the end tag for this element.
119 
120         """
121         self._assert_is_element(subelement)
122         self._children.append(subelement)
123 
124     def extend(self, elements):
125         为当前节点扩展 n 个子节点
126         """Append subelements from a sequence.
127 
128         *elements* is a sequence with zero or more elements.
129 
130         """
131         for element in elements:
132             self._assert_is_element(element)
133         self._children.extend(elements)
134 
135     def insert(self, index, subelement):
136         在当前节点的子节点中插入某个节点,即:为当前节点创建子节点,然后插入指定位置
137         """Insert *subelement* at position *index*."""
138         self._assert_is_element(subelement)
139         self._children.insert(index, subelement)
140 
141     def _assert_is_element(self, e):
142         # Need to refer to the actual Python implementation, not the
143         # shadowing C implementation.
144         if not isinstance(e, _Element_Py):
145             raise TypeError('expected an Element, not %s' % type(e).__name__)
146 
147     def remove(self, subelement):
148         在当前节点在子节点中删除某个节点
149         """Remove matching subelement.
150 
151         Unlike the find methods, this method compares elements based on
152         identity, NOT ON tag value or contents.  To remove subelements by
153         other means, the easiest way is to use a list comprehension to
154         select what elements to keep, and then use slice assignment to update
155         the parent element.
156 
157         ValueError is raised if a matching element could not be found.
158 
159         """
160         # assert iselement(element)
161         self._children.remove(subelement)
162 
163     def getchildren(self):
164         获取所有的子节点(废弃)
165         """(Deprecated) Return all subelements.
166 
167         Elements are returned in document order.
168 
169         """
170         warnings.warn(
171             "This method will be removed in future versions.  "
172             "Use 'list(elem)' or iteration over elem instead.",
173             DeprecationWarning, stacklevel=2
174             )
175         return self._children
176 
177     def find(self, path, namespaces=None):
178         获取第一个寻找到的子节点
179         """Find first matching element by tag name or path.
180 
181         *path* is a string having either an element tag or an XPath,
182         *namespaces* is an optional mapping from namespace prefix to full name.
183 
184         Return the first matching element, or None if no element was found.
185 
186         """
187         return ElementPath.find(self, path, namespaces)
188 
189     def findtext(self, path, default=None, namespaces=None):
190         获取第一个寻找到的子节点的内容
191         """Find text for first matching element by tag name or path.
192 
193         *path* is a string having either an element tag or an XPath,
194         *default* is the value to return if the element was not found,
195         *namespaces* is an optional mapping from namespace prefix to full name.
196 
197         Return text content of first matching element, or default value if
198         none was found.  Note that if an element is found having no text
199         content, the empty string is returned.
200 
201         """
202         return ElementPath.findtext(self, path, default, namespaces)
203 
204     def findall(self, path, namespaces=None):
205         获取所有的子节点
206         """Find all matching subelements by tag name or path.
207 
208         *path* is a string having either an element tag or an XPath,
209         *namespaces* is an optional mapping from namespace prefix to full name.
210 
211         Returns list containing all matching elements in document order.
212 
213         """
214         return ElementPath.findall(self, path, namespaces)
215 
216     def iterfind(self, path, namespaces=None):
217         获取所有指定的节点,并创建一个迭代器(可以被for循环)
218         """Find all matching subelements by tag name or path.
219 
220         *path* is a string having either an element tag or an XPath,
221         *namespaces* is an optional mapping from namespace prefix to full name.
222 
223         Return an iterable yielding all matching elements in document order.
224 
225         """
226         return ElementPath.iterfind(self, path, namespaces)
227 
228     def clear(self):
229         清空节点
230         """Reset element.
231 
232         This function removes all subelements, clears all attributes, and sets
233         the text and tail attributes to None.
234 
235         """
236         self.attrib.clear()
237         self._children = []
238         self.text = self.tail = None
239 
240     def get(self, key, default=None):
241         获取当前节点的属性值
242         """Get element attribute.
243 
244         Equivalent to attrib.get, but some implementations may handle this a
245         bit more efficiently.  *key* is what attribute to look for, and
246         *default* is what to return if the attribute was not found.
247 
248         Returns a string containing the attribute value, or the default if
249         attribute was not found.
250 
251         """
252         return self.attrib.get(key, default)
253 
254     def set(self, key, value):
255         为当前节点设置属性值
256         """Set element attribute.
257 
258         Equivalent to attrib[key] = value, but some implementations may handle
259         this a bit more efficiently.  *key* is what attribute to set, and
260         *value* is the attribute value to set it to.
261 
262         """
263         self.attrib[key] = value
264 
265     def keys(self):
266         获取当前节点的所有属性的 key
267 
268         """Get list of attribute names.
269 
270         Names are returned in an arbitrary order, just like an ordinary
271         Python dict.  Equivalent to attrib.keys()
272 
273         """
274         return self.attrib.keys()
275 
276     def items(self):
277         获取当前节点的所有属性值,每个属性都是一个键值对
278         """Get element attributes as a sequence.
279 
280         The attributes are returned in arbitrary order.  Equivalent to
281         attrib.items().
282 
283         Return a list of (name, value) tuples.
284 
285         """
286         return self.attrib.items()
287 
288     def iter(self, tag=None):
289         在当前节点的子孙中根据节点名称寻找所有指定的节点,并返回一个迭代器(可以被for循环)。
290         """Create tree iterator.
291 
292         The iterator loops over the element and all subelements in document
293         order, returning all elements with a matching tag.
294 
295         If the tree structure is modified during iteration, new or removed
296         elements may or may not be included.  To get a stable set, use the
297         list() function on the iterator, and loop over the resulting list.
298 
299         *tag* is what tags to look for (default is to return all elements)
300 
301         Return an iterator containing all the matching elements.
302 
303         """
304         if tag == "*":
305             tag = None
306         if tag is None or self.tag == tag:
307             yield self
308         for e in self._children:
309             yield from e.iter(tag)
310 
311     # compatibility
312     def getiterator(self, tag=None):
313         # Change for a DeprecationWarning in 1.4
314         warnings.warn(
315             "This method will be removed in future versions.  "
316             "Use 'elem.iter()' or 'list(elem.iter())' instead.",
317             PendingDeprecationWarning, stacklevel=2
318         )
319         return list(self.iter(tag))
320 
321     def itertext(self):
322         在当前节点的子孙中根据节点名称寻找所有指定的节点的内容,并返回一个迭代器(可以被for循环)。
323         """Create text iterator.
324 
325         The iterator loops over the element and all subelements in document
326         order, returning all inner text.
327 
328         """
329         tag = self.tag
330         if not isinstance(tag, str) and tag is not None:
331             return
332         if self.text:
333             yield self.text
334         for e in self:
335             yield from e.itertext()
336             if e.tail:
337                 yield e.tail
338 
339 节点功能一览表
节点功能一览表

 

由于 每个节点 都具有以上的方法,并且在上一步骤中解析时均得到了root(xml文件的根节点),so   可以利用以上方法进行操作xml文件。

a. 遍历XML文档的所有内容

from xml.etree import ElementTree as ET

############ 解析方式一 ############
"""
# 打开文件,读取XML内容
str_xml = open('xo.xml', 'r').read()

# 将字符串解析成xml特殊对象,root代指xml文件的根节点
root = ET.XML(str_xml)
"""
############ 解析方式二 ############

# 直接解析xml文件
tree = ET.parse("xo.xml")

# 获取xml文件的根节点
root = tree.getroot()


### 操作

# 顶层标签
print(root.tag)


# 遍历XML文档的第二层
for child in root:
    # 第二层节点的标签名称和标签属性
    print(child.tag, child.attrib)
    # 遍历XML文档的第三层
    for i in child:
        # 第二层节点的标签名称和内容
        print(i.tag,i.text)
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 ggg

dsfs

sdf

sdf

 

sdf

 

sfd

sdf

 

 

 

 

 

 

 

 

 

 

 

 

九、requests        pass

Python标准库中提供了:urllib等模块以供Http请求,但是,它的 API 太渣了。它是为另一个时代、另一个互联网所创建的。它需要巨量的工作,甚至包括各种方法覆盖,来完成最简单的任务

十、logging          pass

用于便捷记录日志且线程安全的模块

十一、系统命令  pass

十二、shutil      pass

高级的 文件、文件夹、压缩包 处理模块

 

十三、paramiko     pass

paramiko是一个用于做远程控制的模块,使用该模块可以对远程服务器进行命令或文件操作,值得一说的是,fabric和ansible内部的远程管理就是使用的paramiko来现实。

十四、time               pass

时间相关的操作,时间有三种表示方式:

  • 时间戳               1970年1月1日之后的秒,即:time.time()
  • 格式化的字符串    2014-11-11 11:11,    即:time.strftime('%Y-%m-%d')
  • 结构化时间          元组包含了:年、日、星期等... time.struct_time    即:time.localtime()
 1 #_*_coding:utf-8_*_
 2 __author__ = 'Alex Li'
 3 
 4 import time
 5 
 6 
 7 # print(time.clock()) #返回处理器时间,3.3开始已废弃 , 改成了time.process_time()测量处理器运算时间,不包括sleep时间,不稳定,mac上测不出来
 8 # print(time.altzone)  #返回与utc时间的时间差,以秒计算\
 9 # print(time.asctime()) #返回时间格式"Fri Aug 19 11:14:16 2016",
10 # print(time.localtime()) #返回本地时间 的struct time对象格式
11 # print(time.gmtime(time.time()-800000)) #返回utc时间的struc时间对象格式
12 
13 # print(time.asctime(time.localtime())) #返回时间格式"Fri Aug 19 11:14:16 2016",
14 #print(time.ctime()) #返回Fri Aug 19 12:38:29 2016 格式, 同上
15 
16 
17 
18 # 日期字符串 转成  时间戳
19 # string_2_struct = time.strptime("2016/05/22","%Y/%m/%d") #将 日期字符串 转成 struct时间对象格式
20 # print(string_2_struct)
21 # #
22 # struct_2_stamp = time.mktime(string_2_struct) #将struct时间对象转成时间戳
23 # print(struct_2_stamp)
24 
25 
26 
27 #将时间戳转为字符串格式
28 # print(time.gmtime(time.time()-86640)) #将utc时间戳转换成struct_time格式
29 # print(time.strftime("%Y-%m-%d %H:%M:%S",time.gmtime()) ) #将utc struct_time格式转成指定的字符串格式
30 
31 
32 
33 
34 
35 #时间加减
36 import datetime
37 
38 # print(datetime.datetime.now()) #返回 2016-08-19 12:47:03.941925
39 #print(datetime.date.fromtimestamp(time.time()) )  # 时间戳直接转成日期格式 2016-08-19
40 # print(datetime.datetime.now() )
41 # print(datetime.datetime.now() + datetime.timedelta(3)) #当前时间+3天
42 # print(datetime.datetime.now() + datetime.timedelta(-3)) #当前时间-3天
43 # print(datetime.datetime.now() + datetime.timedelta(hours=3)) #当前时间+3小时
44 # print(datetime.datetime.now() + datetime.timedelta(minutes=30)) #当前时间+30分
45 
46 
47 #
48 # c_time  = datetime.datetime.now()
49 # print(c_time.replace(minute=3,hour=2)) #时间替换
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1 rhgth
2 jojjo
3 jjjjjjjjjjjjj
4 jjjjj
5 jjjjjjjj
6 jjjjjjjj
7 jjjjjj
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posted @ 2017-09-30 03:08  明宣  阅读(113)  评论(0编辑  收藏  举报