keypressed() and onCLick() implementation problem in IE - php

Question

I've the following input text box and a button.
<div id="sender" onKeyUp="keypressed(event);">
Your message: <input type="text" name="msg" size="70" id="msg" />
<button onClick="doWork();">Send</button>
</div>
The keypressed(event) function actually detects if the key being pressed is "Enter" and calls the doWork() function.
function keypressed(e){
if(e.keyCode=='13'){
doWork();
}
}
This code seems to work fine in Chrome & Firefox. But in IE, the function seems to called twice.
Can anyone help me tweak the code so that it works properly in IE also.
Thanks
EDITED:
Whole ajax codes
<!--
var httpObject = null;
var link = "";
var timerID = 0;
var nickName = "Unname"; //"<?php echo $nickname; ?>";
// Get the HTTP Object
function getHTTPObject(){
if (window.ActiveXObject) return new ActiveXObject("Microsoft.XMLHTTP");
else if (window.XMLHttpRequest) return new XMLHttpRequest();
else {
alert("Your browser does not support AJAX.");
return null;
}
}
// Change the value of the outputText field
function setOutput(){
if(httpObject.readyState == 4){
var response = httpObject.responseText;
var objDiv = document.getElementById("result");
objDiv.innerHTML += response;
objDiv.scrollTop = objDiv.scrollHeight;
var inpObj = document.getElementById("msg");
inpObj.value = "";
inpObj.focus();
}
}
// Change the value of the outputText field
function setAll(){
if(httpObject.readyState == 4){
var response = httpObject.responseText;
var objDiv = document.getElementById("result");
objDiv.innerHTML = response;
objDiv.scrollTop = objDiv.scrollHeight;
}
}
// Implement business logic
function doWork(){
httpObject = getHTTPObject();
if (httpObject != null) {
link = "message.php?nick="+nickName+"&msg="+encodeURIComponent(document.getElementById('msg').value);
httpObject.open("GET", link , true);
httpObject.onreadystatechange = setOutput;
httpObject.send(null);
}
}
// Implement business logic
function doReload(){
httpObject = getHTTPObject();
var randomnumber=Math.floor(Math.random()*10000);
if (httpObject != null) {
link = "message.php?all=1&rnd="+randomnumber;
httpObject.open("GET", link , true);
httpObject.onreadystatechange = setAll;
httpObject.send(null);
}
}
function UpdateTimer() {
doReload();
timerID = setTimeout("UpdateTimer()", 5000);
}
function keypressed(e){
if(e.keyCode=='13'){
doWork();
}
}
//-->

Answer 1

If someone is facing a similar problem, this could be useful.
I solved the problem by detecting IE browser using PHP script and discarding the onKeyUp() function while rendering HTML for IE.
IE Detection PHP script
//Detect IE function
function detectIE() {
if (isset($_SERVER['HTTP_USER_AGENT']) && (strpos($_SERVER['HTTP_USER_AGENT'], 'MSIE') !== false))
return true;
else
return false;
}
And this is how i changed the event handling.
<div id="sender" <?php if (detectIE()) { /*do nothing */ } else { echo "onKeyUp=\"keypressed(event);\""; } ?> >
Your message: <input type="text" name="msg" size="70" id="msg" />
<button onClick="doWork();">Send</button>
</div>