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字符串中的 字符替换解决办法

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Release: 2016-06-13 10:13:57
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字符串中的 字符替换
我现在有一些如这样的字符串

[3]/([2]*[2])

其中[3] [2] 分别对应我系统里的3号和2号变量 $e3 和$e2

希望将上面的式子通过程序转换成如下字符串

$e3/($e2*$e2)

这样就可以用eval计算了。

请问如何实现这个转换?有什么方法。



------解决方案--------------------
$str='[3]/([2]*[2])';
for($i=1;$i $str=str_replace('['.$i.']', '$e'.$i, $str);
}
echo $str;
?>
------解决方案--------------------

C/C++ code
$str = '[3]/([2]*[2])';echo procnum($str);function procnum($str){    //$i = 0;    while (preg_match('/(\[\d+\])/',$str)){        $str = preg_replace('/\[(\d+)\]/',"\$e\$1",$str,1);    //    if($i++>100) break;    }    return $str;}<div class="clear">
                 
              
              
        
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