一直以来,也经常有人问这个问题。包括Java下Map的元素的遍历。我在水木清华的Java版也回答过这个问题。
.NET平台下:
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Java环境下:
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点评:
.NET环境下,引入了foreach的写法,但是IDictionary和ICollection的GetEnumerator()方法返回的类型是不一样的,这一点,很容易让人迷惑,初学者很多都会写错。如下是初学者常用的写法:
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Java下,使用起来的方式,有点麻烦,很多初学者,不使用恰当的方法遍历Map,甚至一些写了多年Java程序员都是用比较笨的办法。
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