Implementasi AJAX mirip $.ajax jQuery.

gistfile1.txt

var MyLib = MyLib || {};

MyLib.AJAX = function (options) {
    if ("method" in options && 
        "url" in options &&
        "onSuccess" in options) {

        var xhr,
            method = options.method,
            data   = options.data,
            url    = options.url,
            async  = options.async || true,
            onSuccess = options.onSuccess,
            onFailure = options.onFailure || function () { };

        try {
            xhr = new XMLHttpRequest();
        } catch (e) {
            xhr = new ActiveXObject("Microsoft.XMLHTTP");
        }

        if (xhr === undefined) {
            alert("TIDAK MENDUKUNG AJAX");
        }

        xhr.onreadystatechange = function () {
            if (xhr.readyState === 4) {
                if (xhr.status === 200) {
                    onSuccess(xhr.responseText);
                } else {
                    onFailure();
                }
            }
        };

        xhr.open(method, 
                 url, 
                 async);

        xhr.send(data);
    } else {
        alert("Options tidak lengkap");
    }
};

// Contoh penggunaan

var HandleData = function (data) {
    // do something
};

var HandleError = function () {
    // do something
};

var LogBaru = function (data) {
    // do something
};

MyLib.AJAX({ 
    method    : "GET",
    url       : "http://contoh.com/ajaxapi/departments",
    async     : true,
    onSuccess : HandleData,
    onFailure : HandleError
});

MyLib.AJAX({
    method    : "POST",
    url       : "http://contoh.com/ajaxapi/departments/" + dept_no,
    async     : true,
    onSuccess : LogBaru,
    onFailure : HandleError
});