javascript - Ajax在jsp中进行id检查仅返回相同的结果

Question

我一直在jsp中使用ajax来检查id。因此，当用户尝试创建一个新帐户时，他们将输入他们想要创建的 id，ajax 将检查数据库中是否存在相同的 id。如果有，则返回“n”，并在jsp中将其更改为“不可用”。如果没有相同的 id，则返回“y”，并在 jsp 中更改为“available”。问题是它似乎只返回“n”。

这是 JavaScript。

 $('#email').keyup(function(){
    var str = $(this).val();
    var server = "idcheck";     
    $.post(server, {"email":str}, function(data){
        if(data.ret =='y'){
            $('#valid_check').html("available");
        }else if(data.ret =='n'){
            $('#valid_check').html("unavailable");
        }

        });
    });

这是 join.jsp。

<label id="valid_check">check if you can use id</label>
<input id="email" name="email" type="email" class="form-style-join" placeholder="ex> mymail477@gmail.com" />    

这是 Controller 。

@RequestMapping(value = "/idcheck", method = { RequestMethod.GET, RequestMethod.POST })
public @ResponseBody HashMap<String,String> idCheck(HttpServletRequest request,
        HttpServletResponse response){
    response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
    response.setHeader("Access-Control-Max-Age", "3600");
    response.setHeader("Access-Control-Allow-Headers", "x-requested-with");
    response.setHeader("Access-Control-Allow-Origin", "*");
    response.setContentType("application/json");
    response.setCharacterEncoding("UTF-8");

    String mem_id = request.getParameter("mem_id"); 
    int ret= memberMapper.memberIDCheck(mem_id);

    HashMap<String,String> map = new HashMap<String,String>();


    if(ret == 1){
        map.put("ret", "y");

    }else if( ret != 1){
        map.put("ret", "n");
    }

    System.out.println(map);
    return map;
}

这是映射器。

@Select("SELECT count(*) AS cnt FROM `member` WHERE mem_id=#{mem_id}")
public int memberIDCheck(String mem_id); 

Answer 1

首先，您需要确保在 Spring Controller 方法中获取输入字段值。因此，您在这里发送一个参数 {"email":str} 但在 Controller 中您正在寻找“mem_id”。

试试这个代码:

@RequestMapping(value = "/idcheck", method =  RequestMethod.POST })
public @ResponseBody HashMap<String,String> idCheck(HttpServletRequest request, HttpServletResponse response, @RequestBody String email){
response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
response.setHeader("Access-Control-Max-Age", "3600");
response.setHeader("Access-Control-Allow-Headers", "x-requested-with");
response.setHeader("Access-Control-Allow-Origin", "*");
response.setContentType("application/json");
response.setCharacterEncoding("UTF-8");

String mem_id = email; 
int ret= memberMapper.memberIDCheck(mem_id);

HashMap<String,String> map = new HashMap<String,String>();


if(ret == 1){
    map.put("ret", "y");

}else if( ret != 1){
    map.put("ret", "n");
}

System.out.println(map);
return map;

}

这里我添加了一个@RequestBody。这样ajax请求中绑定(bind)的数据“email”就可以映射到方法参数email上。