utf-8编码转换成gb2312

[code]<script>  
function  chinesefromutf8url(strutf8)    
{  
           var  bstr  =  "";  
           var  noffset  =  0; 
 //  processing  point  on  strutf8               
           if(  strutf8  ==  ""  )  
               return  "";                 
           strutf8  =  strutf8.tolowercase();  
           noffset  =  strutf8.indexof("%e");  
           if(  noffset  ==  -1  )  
               return  strutf8;  

           while(  noffset  !=  -1  )  
           {  
               bstr  +=  strutf8.substr(0,  noffset);  
               strutf8  =  strutf8.substr(noffset,  strutf8.length  -  noffset);  
               if(  strutf8  ==  ""    ¦  ¦  strutf8.length  <  9  )      //  bad  string  
                   return  bstr;  

               bstr  +=  utf8codetochinesechar(strutf8.substr(0,  9));  
               strutf8  =  strutf8.substr(9,  strutf8.length  -  9);  
               noffset  =  strutf8.indexof("%e");