Network Programming in .NET

If you have an Iframe on a page, and you press the back button, then oftentimes, only the Iframe goes back in it’s history, not the containing page.

 

There are a few workarounds for this, this is just a proposal, if it helps…

 

firstly, if you have a pre-loader on the iframe, such as…

 

graph.contentWindow.document.write(‘Please wait…’);
graph.src = ‘someurl’

 

when you can poll the Iframe for a change in the "Please wait message". (Note, that the url that you are redirecting to must be on the same domain as the parent page, or else you get a security exception)

 

// 951 – back button fix. 
 var wasGraphLoaded = false;
 setTimeout(‘checkGraph()’,500);
 function checkGraph()
 {
  if (imgGraph.document.body.innerHTML.indexOf("…")==-1)
  {
   // Graph must be loaded…
   wasGraphLoaded = true;  
   
  }
  else
  {
   // Graph isn’t loaded.
   if (wasGraphLoaded)
   {
    // The back button bust have been pressed
    window.history.go(-1);
   }
  }
  setTimeout(‘checkGraph()’,500);
 }