Note: Please check JavaScript Utility Functions Note.

The following function will allow you to change the value of a specified parameter from the URL. You just have to pass the parameter name and desired parameter value.

/*Define the namespaces*/
var JavaScript = {};
JavaScript.Utils = {};
JavaScript.Utils.URL = {};

JavaScript.Utils.URL.ReplaceUrlParam = function(name, value) {
    name = name.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]");
    var regexS = "[\\?&]" + name + "=([^&#]*)";
    var regex = new RegExp(regexS);
    var results = regex.exec(window.location.href);
    if (results == null)
        return false;
    else {
        var form = document.forms[0];
        if (form) {
            form.action = form.action.replace(results[0], results[0].replace(/=(.*)/, '=' + value));
        }
    }
};