layui加載層的寫法

<script type="text/javascript" src="jquery-1.8.3.min.js"></script>
    <script type="text/javascript" src="layer/layer.js"></script>

//在js中寫出前后加載的函數 加載層
 1 ; !function () {
            layer.config({//加載擴展模塊  
                extend: '../lib/jquery.plugins/layer/extend/layer.ext.js'
            });
            layer.ready(function () {
            });
        }();

        function ityzl_SHOW_LOAD_LAYER() {
            return layer.msg('努力中...', { icon: 16, shade: [0.5, '#f5f5f5'], scrollbar: false, offset: '50%', time: 300000 });
        }
        function ityzl_CLOSE_LOAD_LAYER(index) {
            layer.close(index);
        }
        function ityzl_SHOW_TIP_LAYER() {
            layer.msg('恭喜您，加載完成！', { time: 1000, offset: '50%' });
        } 

//ajax做處理 當然 也可以是點擊事件。
var i;
        $(function () {
            $.ajax({
                type: "POST",
                dataType: "text",
                url: "",
                beforeSend: function () {
                   i = ityzl_SHOW_LOAD_LAYER();
                },
                success: function (msg) {
                    ityzl_CLOSE_LOAD_LAYER(i);
                    ityzl_SHOW_TIP_LAYER();
                },
                error: function (e, jqxhr, settings, exception) {
                    ityzl_CLOSE_LOAD_LAYER(i);
                }
            });
        });