实现查询ajax的action,ajax 怎么获取action中返回的SUCCESS和ERROR。。

没怎么学js，我是想验证用户名是否存在的，网上的能够跑出来，但是思路理不顺，，

代码

jsp

Created by IntelliJ IDEA.

User: Administrator

Date: 2017/7/8

Time: 11:47

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--%>

Title

ajax异步测试

$("input").blur(function () {

$.ajax({

type:"POST",

url:"${pageContext.request.contextPath}/user/ifuser",

data:"userinfo.u_name=" + $("input").val(),

success: function(message){

/**

}

}

)

})

action

@Action(value = "/ifuser", results = {

@Result(name = "success",location = "/test.jsp"),

@Result(name = "error",location = "/test.jsp")

})

public String regYz(){

System.out.println("sss"+userinfo.getU_name());

HttpServletRequest request = ServletActionContext.getRequest();

boolean flag = userService.regYZ(userinfo);

if (flag){

request.setAttribute("saveMsg", "已经存在");

System.out.println("已经存在");

return ERROR;

}else {

System.out.println("不存在，可以注册");

return SUCCESS;

}

}

我是想获取到SUCCESS 或者error来判断是否存在，不知道ajax怎么获取到。谢谢大家