I'm using the following AJAX code to send GET vars to my processing PHP file. This works great as is except that it will not accept a *&* (AND symbol) in the text input. It trys to pass what is after the *&* as a new GET var. I totaly get what is happening, just don't get how to fix it. I hope my example code is sufficient.

HTML:

<input type="text" class="inputbox" value="pb&j" id="input_name" name="input_name" onblur="javascript:makeRequest('my_file.php?new=',this.value);"/>

Javascript:

var http_request = false;
function makeRequest(url, parameters) { //alert(parameters)
    http_request = false;
    if (window.XMLHttpRequest) { // Mozilla, Safari,...
        http_request = new XMLHttpRequest();
        if (http_request.overrideMimeType) {
            // set type accordingly to anticipated content type
            //http_request.overrideMimeType('text/xml');
            http_request.overrideMimeType('text/html');
        }
    } else if (window.ActiveXObject) { // IE
        try {
            http_request = new ActiveXObject("Msxml2.XMLHTTP");
        } catch (e) {
            try {
                http_request = new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e) {}
        }
    }
    if (!http_request) {
        alert('Cannot create XMLHTTP instance');
        return false;
    }
    http_request.onreadystatechange = alertContents;

    // FOR POST VARS
    //http_request.open('POST', url, true);
    //http_request.send(parameters);

    // FOR GET VARS
    http_request.open('GET', url + parameters + "&time=" + get_date(), true);
    http_request.send(null);
}

function alertContents() {
if (http_request.readyState == 4) {
 if (http_request.status == 200) {
    //alert(http_request.responseText);
    result = http_request.responseText;
    document.getElementById('myspan').innerHTML = result;
 } else {
    alert('There was a problem with the request.');
 }
}
}

My solutions was to add the replace() function at line 2 of the following code.

function makeRequest(url, parameters) {
        parameters = parameters.replace(/&/g,"%26");
    http_request = false;

        ... rest of function
}

another way is with the 'escape' function. It will take care of other characters as well.

param = escape("hello&goodbye");

will set param to: "hello%26goodbye"

There is also an 'unescape' function that will do the reverse.