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  • 零基础学python-8.7 字典常用方法

    1.列举字典的值、键与对

    >>> d={'a':1,'b':2,'c':3,'d':4}
    >>> list(d.keys ())
    ['c', 'd', 'a', 'b']
    >>> list(d.values ())
    [3, 4, 1, 2]
    >>> list(d.items ())
    [('c', 3), ('d', 4), ('a', 1), ('b', 2)]
    >>> 

    2.获取相对位置

    >>> d={'a':1,'b':2,'c':3,'d':4}
    >>> d.get ('a')
    1
    >>> 

    3.合并(注意:不能够使用+,只能够使用update)

    >>> d={'a':1,'b':2,'c':3,'d':4}
    >>> e={'e':5}
    >>> d+e
    Traceback (most recent call last):
      File "<pyshell#30>", line 1, in <module>
        d+e
    TypeError: unsupported operand type(s) for +: 'dict' and 'dict'
    >>> d.update (e)
    >>> d
    {'c': 3, 'e': 5, 'd': 4, 'a': 1, 'b': 2}
    >>> 

    4.删除

    >>> d={'a':1,'b':2,'c':3,'d':4}
    >>> d.pop ('a')
    1
    >>> d
    {'c': 3, 'd': 4, 'b': 2}
    >>> del d['b']
    >>> d
    {'c': 3, 'd': 4}
    >>> 

    就说到这里,谢谢大家

    ------------------------------------------------------------------

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    版权声明:本文为博主原创文章,未经博主允许不得转载。

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  • 原文地址:https://www.cnblogs.com/raylee2007/p/4774470.html
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