//设置图片的大小

function Reset_ImgSize(obj, MaxW, MaxH)
{
    if (obj != null) imageObject = obj;
    var state=imageObject.readyState;
    var oldImage = new Image();
    oldImage.src = imageObject.src;
    var dW=oldImage.width; var dH=oldImage.height;
    a=dW/MaxW; b=dH/MaxH; 
    if(b>a) a=b;
    dW=dW/a; dH=dH/a;
    if(dW > 0 && dH > 0)
        imageObject.width=dW;imageObject.height=dH;
    if(state!='complete' || imageObject.width>MaxW || imageObject.height>MaxH) {
        setTimeout("ResizeImage(null,"+MaxW+","+MaxH+")",40); 
    }
}