preg_replace 不支持元字符"\b"???
我想匹配一个单词，例如hi，想用\b标出开始与结束。但是用这个函数无法执行。后来在网上查了说是用/作为定界符，但是匹配的时候还是将所有的都匹配了。无法做到匹配单独的hi这个单词？请高手赐教一下
------解决方案--------------------
/\bhi\b/ 也行的, 你试试
------解决方案--------------------
- PHP code
$a ='fhia hi fefefhi hiasdf hi';$b = '/\bhi\b/';$c = 'jj';echo preg_replace($b,$c,$a);<div class="clear">
</div>
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