jquery中如何获取图片真实大小

$("<img/>") // Make in memory copy of image to avoid css issues  在内存中创建一个img标记

    .attr("src", $(''#imgid").attr("src"))

    .load(function() {

        pic_real_width = this.width;   // Note: $(this).width() will not

        pic_real_height = this.height; // work for in memory images.

    });