# -*- coding: utf-8 -*-
# @Time : 2018/12/20 4:28 PM
# @Author : cxa
# @File : DictHelper.py
# @Software: PyCharm
# -*- coding: utf-8 -*-
# @Time : 2018/10/16 10:34
# @Author : cxa
# @File : dictMethod.py
# @Software: PyCharm
# -*- coding: utf-8 -*-
"""
requests.structures
~~~~~~~~~~~~~~~~~~~
Data structures that power Requests.
"""
from collections import OrderedDict
from collections.abc import Mapping, MutableMapping, Iterable
class CaseInsensitiveDict(MutableMapping):
"""A case-insensitive ``dict``-like object.
Implements all methods and operations of
``MutableMapping`` as well as dict's ``copy``. Also
provides ``lower_items``.
All keys are expected to be strings. The structure remembers the
case of the last key to be set, and ``iter(instance)``,
``keys()``, ``items()``, ``iterkeys()``, and ``iteritems()``
will contain case-sensitive keys. However, querying and contains
testing is case insensitive::
cid = CaseInsensitiveDict()
cid['Accept'] = 'application/json'
cid['aCCEPT'] == 'application/json' # True
list(cid) == ['Accept'] # True
For example, ``headers['content-encoding']`` will return the
value of a ``'Content-Encoding'`` response header, regardless
of how the header name was originally stored.
If the constructor, ``.update``, or equality comparison
operations are given keys that have equal ``.lower()``s, the
behavior is undefined.
"""
def __init__(self, data=None, **kwargs):
# 初始化的时候进入，初始化一个 OrderedDict()
self._store = OrderedDict()
if data is None:
data = {}
self.update(data, **kwargs) # 把属性加入到 self 的__dict__里，也是一个字典操作。
def __setitem__(self, key, value):
# key.lower() 把字符串转换成小写
# 这句话在属性赋值的时候会被调用。实现的无视字母大小写进行赋值
self._store[key.lower()] = (key, value)
# setattr(self,key.lower(),(key, value))
def __getitem__(self, key):
return self._store[key.lower()][1]
def __delitem__(self, key):
del self._store[key.lower()]
def __iter__(self):
return (casedkey for casedkey, mappedvalue in self._store.values()) # 调用父类的__iter__
def __len__(self):
return len(self._store)
def lower_items(self):
"""Like iteritems(), but with all lowercase keys."""
return (
(lowerkey, keyval[1])
for (lowerkey, keyval)
in self._store.items()
)
def __eq__(self, other):
if isinstance(other, Mapping):
other = CaseInsensitiveDict(other)
else:
return NotImplemented
# Compare insensitively
return dict(self.lower_items()) == dict(other.lower_items())
# Copy is required
def copy(self):
return CaseInsensitiveDict(self._store.values())
def __repr__(self):
# print 的时候会进入
print(isinstance(self.items(), Iterable)) # 输入可迭代对象，此时
##内部实际
# dict(iterable)
# d = {}
# for k, v in iterable: #会调用__iter__
# d[k] = v
return str(dict(self.items()))
if __name__ == '__main__':
dic= {
"Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8",
"Accept-Encoding": "gzip, deflate",
"Accept-Language": "zh,en-US;q=0.9,en;q=0.8,zh-CN;q=0.7,zh-TW;q=0.6",
"Connection": "keep-alive",
"Upgrade-Insecure-Requests": "1",
"user-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36",
}
dic1 = CaseInsensitiveDict(dic)
print(dic1.get("UseR-agEnt"))
