//图片预览自适应大小
var __raye_image_preview_object;
function ResizeImage(obj, MaxW, MaxH) {
    if (obj == null) return ;
    __raye_image_preview_object = obj;
    
    var state=__raye_image_preview_object.readyState;
	if(state && state!='complete') {
        setTimeout("ResizeImage(null,"+MaxW+","+MaxH+")",50);
		return;
    }
    var oldImage = new Image();
    oldImage.src = __raye_image_preview_object.src;
    var dW=oldImage.width; var dH=oldImage.height;
    if(dW>MaxW || dH>MaxH) {
        a=dW/MaxW; b=dH/MaxH;
        if(b>a) a=b;
        dW=dW/a; dH=dH/a;
    }
    if(dW > 0 && dH > 0) {
        __raye_image_preview_object.width=dW;
		__raye_image_preview_object.height=dH;
	}
}