PHP数组访问一些有关问题的猜测
PHP数组访问一些问题的猜测
首先:据说,PHP的数组是抄袭了PERL的数组,但对它的使用做了简化。
那么,要访问一个数组中的成员自然是:
$数组名[键名]
或者
$数组名{键名}
在PERL中,[]索引指的是数组,{}专用于散列数组。
但是PHP官方文档中并没有{}索引方式的说明。只是在用户评注中存在。自然,我想这些用户一定是看过PHP源码的。也许是不经意测试出来的。
但不管怎么说,如果你不看源码,是无法得知二者的真正区别的。
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另外有一点,那就是,可以用数组方式访问字符串中的单个字符。但是,如果变量为空。用数组方式向其中写一个字串,那就成数组了。
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对于字符串,我个人喜好使用{}式索引访问。这样做的根本目的,是为了与数组相区分。标明,此变量是字符串。
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对于[]与{}的区别,改日有空需要看一下源码了。在些仅作个记录。

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