【www.gdgbn.com--js教程】

 
 
  网页特效:toi_upimg();">

<script>
function toi_upimg()
{
  var form = document.dform;
  var isrc = form.ifile.value;
  var pos = isrc.lastindexof(".");
  var img = new image();

  // on load
  img.onload = function () {
    var width = img.width;
    var height = img.height;
    img.onload = "";
    if (width > 480 || height > 320)
    {
      // => 480*360
      var ratio1 = 320/width;
      var ratio2 = 240/height;
      if (ratio1 > ratio2)
      {
        width = parseint(ratio2 * width);
        height = 240;
      }
      else
      {
        width = 320;
        height = parseint(ratio1 * height);
      }     
      alert("注意：图片过大, 系统自动进行了一些调整");
 }
   
    toi_img.src = img.src;
    toi_img.width = width;
    toi_img.height = height;
  form.picwidth.value = width;
  form.picheight.value = height;
  form.mserver.value = "no";
    form.xpost.value = "0";
    form.ypost.value = "0";
    form.xposy.value = "0";
    form.yposy.value = "0";
    form.xposa.value = "0";
    form.yposa.value = "0";
 if (form.title.value == "")
    {
      var pos2 = isrc.lastindexof("");
      form.title.value = isrc.substring(pos2+1,pos);
    }
    toi_update();
    delete img;
  };

  // on error
    img.onerror = function () {
    img.onerror = "";
    alert("注意：您刚刚试图上载的一个文件似乎不是合法图片");
    delete img;
  };

  // store the source address
  if (navigator.appversion.indexof("msie 7") >= 0)
  {
   document.getelementbyid("filterimage").filters.item("dximagetransform.microsoft.alphaimageloader").src = isrc;
   img.src = document.getelementbyid("filterimage").filters.item("dximagetransform.microsoft.alphaimageloader").src;
  }
  else
  {
   img.src = isrc;
  }
}
</script>

本文来源：http://www.gdgbn.com/wangyezhizuo/27554/