$.get()和$.post()、$.ajax()

 // 异步的几种基本写法

 1　<script type="text/javascript">
    function fn1(){
        //get异步访问
        $.get(
            "/WEB22/ajaxServlet2", //url地址
            {"name":"张三","age":25}, //请求参数
            function(data){ //执行成功后的回调函数
                //{"name":"tom","age":21}
                alert(data.name);
            },
            "json"
        );
    }
    function fn2(){
        //post异步访问
        $.post(
            "/WEB22/ajaxServlet2", //url地址
            {"name":"李四","age":25}, //请求参数
            function(data){ //执行成功后的回调函数
                alert(data.name);
            },
            "json"
        );
    }
    function fn3(){
        $.ajax({
            url:"/WEB22/ajaxServlet2",
            async:true,
            type:"POST",
            data:{"name":"lucy","age":18},
            success:function(data){
                alert(data.name);
            },
            error:function(){
                alert("请求失败");
            },
            dataType:"json"
        });
    }
</script>