Image swap with testing

[Haunter]

I have a calendar that is used to select a date and then display an image based on that date. Now future dates of the pictures dont exist on the server. I need to test to see if an image exists before displaying it. If the image does not exist I want to display a default image.

    var imgDefault  = "day-2005-03-03.png";
	var imgSrc      = "day-2005-03-04.png";
	var imgW        = "30";
	var imgH        = "30";
    var imgBaseDir  = "";
    var imgExt      = ".png";
    var imgBaseName = "day-";
	var imgNew      = "";
	var urlBase     = "[URL unfurl="true"]http://localhost/";[/URL]

function dateChanged(calendar) {
    if (calendar.dateClicked) {
      var y = calendar.date.getFullYear();
      var m = calendar.date.getMonth() + 1;     
      var d = calendar.date.getDate();      
		if (m < 10) {
			m = "0" + m;
		}
		if (d < 10) {
			d = "0" + d;
		}

		 imgNew = urlBase + imgBaseDir  + "/" +imgBaseName + y + "-" + m + "-" + d + imgExt;
		 
		 testImage(imgNew);
		
    }
  };

function testImage(URL) { 
   var tester=new Image(); 
   tester.onLoad=switchImage(graph, imgNew ); 
   tester.onError=switchImage(graph, imgDefault); 
   tester.src=URL; 
} 


function switchImage(imgName, imgSrc) 
{
  if (document.images)
  {
    if (imgSrc != "none")
    {
      document.images.graph.src = imgSrc;
    }
  }
}

<img src="day-2005-03-04.png" name="graph">

Any Help would be greatly appreciated, Thank



haunter@battlestrata.com

 

[BillyRayPreachersSon]

A quick search of the forum shows this post I made a while back:

http://www.tek-tips.com/viewthread.cfm?qid=864035

You might also consider using server-side code to return a default image if none exists to cater for browsers that don't support the image onerror event.

Hope this helps,
Dan


The answers you get are only as good as the information you give!