How to find the width of an image before it loads.

I need to know the width of an image before it is called in the html source. I know the name of the image and I'm trying to use javascript to discover the width. This returns a vale of 0 for the width.


var img = new Image();
img.src = "http://mysite.com/graphics/myimage.png"
window.confirm(img.width);
Gary SamuelsPlant ManagerAsked:
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Randy PooleCommented:
There is no way to know before it is loaded.  You can however catch this info before you add it to your page and do what needs to be done:
img = new Image();
img.onload = function() {
  alert("(" + this.width + "x" + this.height+")");
};
img.src = "http://mysite.com/graphics/myimage.png";

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duncanb7Commented:
You can do get the image width before adding it into DOM

Duncan    
<script type="text/javascript">
var getImageSize = function(src) {
    var img = new Image();
    $(img).bind('load', function(e) {
        var height = img.height;
        var width = img.width;
      //  document.write('width:' + width + ', height: ' + height);
	  alert("width="+width);
    });
    img.src = src;
};	
getImageSize('http://localhost/data/php/water.jpg');
</script>

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