var     flag=false;   
    function     DrawImage(ImgD){   
          var     image=new     Image();   
          image.src=ImgD.src;   
          if(image.width>0     &&     image.height>0){   
            flag=true;   
            if(image.width/image.height>=     170/170){   
              if(image.width>170){       
              ImgD.width=170;   
              ImgD.height=(image.height*170)/image.width;   
              }else{   
              ImgD.width=image.width;       
              ImgD.height=image.height;   
              }   
              }   
            else{   
              if(image.height>170)   
      {       
              ImgD.height=170;   
              ImgD.width=(image.width*170)/image.height;             
              }else{   
              ImgD.width=image.width;       
              ImgD.height=image.height;   
              }   
              }   
            }   
    }