php $$变量赋值与详细说明
可变变量名指的是使用一个变量的值作为这个变量的名称,在上面的例子中,通过使用两个$符号,你可以把hello设置成一个变量的名称,例:
,就像下面那样。
通过上面的两个语句,有两个变量被定义:变量$a,装的内容是"hello" 以及变量$hello,装的内容是 "world",于是,下面的语言:
<?php echo "$a ${$a}"; ?> 跟下面的语句的输出完全一致.
<?php echo "$a $hello"; ?> 它们都输出：hello world.文章地址:
转载随意^^请带上本文地址!
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