jquery 验证用户名是否重复代码实例

$("#form-admin-add").validate({
		rules:{
			userName:{
				required:true,
				minlength:2,
				maxlength:16,
				remote: {
     type: "post",
     url: "/checkUserName.html",
     data: {
      userName: function() {
       return $("#userName").val();
      }
     },
     dataType: "html",
     dataFilter: function(data, type) {
     var data=JSON.parse(data)
      if (data.status ==400)
       return false;
      else
       return true;
     }
    }
			},
			password:{
				required:true,
			},
			password2:{
				required:true,
				equalTo: "#password"
			},
			sex:{
				required:true,
			},
			phone:{
				required:true,
				isPhone:true,
			},
			email:{
				required:true,
				email:true,
			},
			roleId:{
				required:true,
			},
		},
		success: function(label) {
   //正确时的样式
   label.text(" ").addClass("success");
  },
   messages: {
   userName: {
    required: "请输入用户名，3-16个字符（字母、数字、下划线），注册后不能更改",
    minlength: "用户名长度不能小于3个字符",
    maxlength: "用户名长度不能大于16个字符",
    remote: "用户名不可用"
   }
  },
		onkeyup:false,
		focusCleanup:true,
		success:"valid"
	});