PHP如何比较变量的大小
php前段通过row获取到A字段的值
$A=$row['A'] ;
想要将$A和“无”这个字做比较，相等的话就显示“无”为红色。请问一下比较这里该怎么写呢。
------解决方案--------------------
$s = '想要将$A和“无”这个字做比较，相等的话就显示“无”为红色。请问一下比较这里该怎么写呢';<br />$A = '无';<br />echo preg_replace("/$A/", '<span style="color:#f00">$0</span>', $s);<br />
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