Sophie: php-manual-zh-5.2.4-1mdv2008.1 noarch

php-manual-zh-5.2.4-1mdv2008.1.noarch.rpm

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>&#13;   当 unset 一个引用，只是断开了变量名和变量内容之间的绑定。这并不意味着变量内容被销毁了。例如：
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><code><font color="#000000">
<font color="#0000BB">&lt;?php<br />$a </font><font color="#007700">= </font><font color="#0000BB">1</font><font color="#007700">;<br /></font><font color="#0000BB">$b </font><font color="#007700">=&amp; </font><font color="#0000BB">$a</font><font color="#007700">;<br />unset(</font><font color="#0000BB">$a</font><font color="#007700">);<br /></font><font color="#0000BB">?&gt;</font>
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>
   不会 unset <CODE
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>$b</CODE
>，只是 <CODE
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>$a</CODE
>。
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>&#13;   再拿这个和 Unix 的 <B
CLASS="command"
>unlink</B
> 调用来类比一下可能有助于理解。
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