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定义
使用键值对，
>>> person = {"name":"keven","age":15,"gender":"male"}
>>> person[‘name‘]
‘keven‘
>>> type(person)
<type ‘dict‘>
字典可以原地修改，即它是可变的。
>>> dict1={} >>> id(dict1) 139736380198256 >>> dict1["name"] = "Keven" >>> id(dict1) 139736380198256 >>> dict1 {‘name‘: ‘Keven‘}
利用元组在建构字典，方法如下：
>>> name = (["first","Google"],["second","Yahoo"]) >>> website = dict(name) >>> website {‘second‘: ‘Yahoo‘, ‘first‘: ‘Google‘}
或者用这样的方法：
>>> ad = dict(name="keven", age=42) >>> ad {‘age‘: 42, ‘name‘: ‘keven‘
基本操作
• len(d)，返回字典(d)中的键值对的数量
>>> city_code = {‘suzhou‘: ‘0512‘, ‘beijing‘: ‘011‘, ‘shanghai‘: ‘012‘, ‘tangshan‘: ‘0315‘}
>>> len(city_code)
4
• d[key]，返回字典(d)中的键(key)的值
>>> city_code["suzhou"] ‘0512‘
• d[key]=value，将值(value)赋给字典(d)中的键(key)
>>> city_code = {‘suzhou‘: ‘0512‘, ‘beijing‘: ‘011‘, ‘shanghai‘: ‘012‘, ‘tangshan‘: ‘0315‘}
>>> city_code["shenzhen"]="1212"
>>> city_code
{‘suzhou‘: ‘0512‘, ‘beijing‘: ‘011‘, ‘shanghai‘: ‘012‘, ‘tangshan‘: ‘0315‘, ‘shenzhen‘: ‘1212‘}
• del d[key]，删除字典(d)的键(key)项（将该键值对删除）
>>> del city_code["shanghai"] >>> city_code {‘suzhou‘: ‘0512‘, ‘beijing‘: ‘011‘, ‘tangshan‘: ‘0315‘, ‘shenzhen‘: ‘1212‘}
• key in d，检查字典(d)中是否含有键为 key 的项
>>> "shenzhen" in city_code True >>> "sz" in city_code False
字典也可以实现格式化字符
>>> city_code = {"suzhou":"0512", "tangshan":"0315", "hangzhou":"0571"}
>>> " Suzhou is a beautiful city, its area code is %(suzhou)s" % city_code
‘ Suzhou is a beautiful city, its area code is 0512
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原文地址：http://www.cnblogs.com/zydev/p/5840024.html
