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;   经常需要在满足某个条件时执行一条语句，而在不满足该条件时执行其它语句，这正是
   <TT
CLASS="literal"
>else</TT
> 的功能。<TT
CLASS="literal"
>else</TT
> 延伸了
   <TT
CLASS="literal"
>if</TT
> 语句，可以在 <TT
CLASS="literal"
>if</TT
>
   语句中的表达式的值为 <TT
CLASS="constant"
><B
>FALSE</B
></TT
> 时执行语句。例如以下代码在
   <CODE
CLASS="varname"
>$a</CODE
> 大于 <CODE
CLASS="varname"
>$b</CODE
> 时显示
   <SAMP
CLASS="computeroutput"
>a is bigger than b</SAMP
>，反之则显示
   <SAMP
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<font color="#0000BB">&lt;?php<br /></font><font color="#007700">if (</font><font color="#0000BB">$a </font><font color="#007700">&gt; </font><font color="#0000BB">$b</font><font color="#007700">) {<br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#DD0000">"a is bigger than b"</font><font color="#007700">;<br />} else {<br />&nbsp;&nbsp;&nbsp;&nbsp;echo </font><font color="#DD0000">"a is NOT bigger than b"</font><font color="#007700">;<br />}<br /></font><font color="#0000BB">?&gt;</font>
</font>
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>
   <TT
CLASS="literal"
>else</TT
> 语句仅在 <TT
CLASS="literal"
>if</TT
> 以及
   <TT
CLASS="literal"
>elseif</TT
>（如果有的话）语句中的表达式的值为
   <TT
CLASS="constant"
><B
>FALSE</B
></TT
> 时执行（参见 <A
HREF="control-structures.elseif.html"
>elseif</A
>）。
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