AJAX request handler 1

[JBellTek]

I am writing a script that hits against the server on keyup to populate a list, but I want to write something to keep the server from getting flooded as they are typing

My thought was to write a handler that would start a global variable countdown and send the request when the counter hit 0, with each subsequent keystroke resetting the counter. That way rapid keystrokes would not all be processed if the user was still typing or a scan gun was used, and only one AJAX request would be sent.

I have been working on this all week. I thought that this would be a common issue. Either I am missing something obvious, or I don't know the keywords to use in searching. If anyone could offer a suggestion, or better yet point me to a tutorial where this kind of thing is done, I would greatly appreciate it.

 

[BillyRayPreachersSon]

You probably want to use the setTimeout and clearTimeout commands. This pseudo-code should give you the general idea, and you can ask in forum216 if you get stuck with the JS:

- initialise a timer handle to be null
- onkeypress (1) if the timer handle is not null, clear it using clearTimeout and set it back to null
- onkeypress (2) set a timer going and store the handle in your variable

I'd say something like 500 ms would be a good time, although you can tweak this.

When the timer fires you know you can fire your AJAX request.

Hope this helps,
Dan

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[JBellTek]

BillyRay:
Thank you for your input.

My final code:

var scnTime;
$(document).ready(function(){
 $("#scanned").focus();

 $("#scanned").keyup(function(){
	 clearTimeout(scnTime);
	 scnTime = setTimeout("loadContent()", 500);
  });
});

It turns out what I was missing was the global declaration of var scnTime.