<!-- 在body下写 -->

<div  id="loading" style="position: absolute;width: 100%;height: 100%;z-index:888;display:none;">

<img src="imgage/loading.gif"  style="position: relative;left: 50%;top: 48%;">

<br />

<span style="position: relative;left: 48%;top: 49%;">数据正在加载中...</span>

</div>

$.ajax({

url:"ajax_Video",

dataType:"json",

beforeSend:function () {

$("#loading").css("display","block");

},

complete:function(){

$("#loading").css("display","none");

},

success:function (data) {

}

送上loading.gif（右键保存即可）：

右键保存

效果图：