求教小疑点

求教小问题。

<?php<br />
<br />
$subject = "abcdef";<br />
$pattern = '/^def/';<br />
preg_match($pattern, $subject, $matches);<br />
print_r($matches);<br />
?><br />

为啥什么也输出不了？

分享到：

------解决方案--------------------
^表示开头，但字符串开头是abc而不是def，所以不能匹配
------解决方案--------------------
因为正则没有匹配，如果你想找最后的应该是 /def$/ ,这样就应该有输出了
------解决方案--------------------

引用:

<?php<br />
<br />
$subject = "abcdef";<br />
$pattern = '/^def/';<br />
preg_match($pattern, $subject, $matches);<br />
print_r($matches);<br />
?><br />

为啥什么也输出不了？

这是最简单问题，正则表达式的特殊字符含义还不是很清楚，建议抽时间学一下正则表达式吧。

Related labels：

def nbsp pattern

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