[End User]

One thing I've noticed about most AJAX handlers out there is that they typically do GET requests...often I have to pass a substantial amount of data 10K, 100K, etc) and GET may fail silently or (even worse) truncate the data when that much data is passed (depending on the browser). I've gone to using POST for most of my AJAX stuff now. The code below is a simple example of what I use....I'm posting it in the hopes that perhaps it may help someone here:

HTML Code:

<script language="Javascript">
function xmlhttpPost(strURL) {
    var xmlHttpReq = false;
    var self = this;
    // Mozilla/Safari
    if (window.XMLHttpRequest) {
        self.xmlHttpReq = new XMLHttpRequest();
    }
    // IE
    else if (window.ActiveXObject) {
        self.xmlHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
    }
    self.xmlHttpReq.open('POST', strURL, true);
    self.xmlHttpReq.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
    self.xmlHttpReq.onreadystatechange = function() {
        if (self.xmlHttpReq.readyState == 4) {
            updatepage(self.xmlHttpReq.responseText);
        }
    }
    self.xmlHttpReq.send(getquerystring());
}

function getquerystring() {
    var form = document.forms['foo'];
    var word = form.word.value;
    qstr = 'w=' + escape(word); 
    return qstr;
}

function updatepage(str){
    document.getElementById("result").innerHTML = str;
}
</script>

And a sample form:

HTML Code:

<form name="foo">
  <p>word: <input name="word" type="text">  
  <input value="Go" type="button" onclick='JavaScript:xmlhttpPost("/somepage.php")'></p>
  <div id="result"></div>
</form>