function Ajax() {
     PageMethod = function(fn, paramArray, successFn, errorFn) {
        var pagePath = "memberpost.aspx";
        //Create list of parameters in the form:  
        //{"paramName1":"paramValue1","paramName2":"paramValue2"}  
        var paramList = '';
        if (paramArray.length > 0) {
            for (var i = 0; i < paramArray.length; i += 2) {
                if (paramList.length > 0) paramList += ',';
                paramList += '"' + paramArray[i] + '":"' + paramArray[i + 1] + '"';
            }
        }
        paramList = '{' + paramList + '}';
        //Call the page method  
        $.ajax({
            type: "POST",
            url: pagePath + "/" + fn,
            contentType: "application/json; charset=utf-8",
            data: paramList,
            dataType: "json",
            success: successFn,
            error: errorFn
        });
    }
}