前台问号传参到后台接收时为null

Js中，这样把值传到后台，serverName能拿到

```![图片说明](https://img-ask.csdn.net/upload/201904/15/1555305857_326976.png)

        $("body").delegate("#selectServer","click",function () {
        var serverName =$("#soso").children("input").val();
        window.location.href = SPRING_URL+"monitor/index?serverName="+serverName;
    })
到后台


![图片说明](https://img-ask.csdn.net/upload/201904/15/1555305936_716617.png)
就成这样了 serverName为null

@RequestMapping("/index")

        public String monitorIndex(@RequestParam(name = "serverName", required = false) String serverName, Model model, HttpServletRequest request) {
    List list =  serverStatusService.selectAllServerStatus(serverName);
       model.addAttribute("serverList",JSONObject.toJSONString(list));
        return "/monitor/monitor";
    }

![图片说明](https://img-ask.csdn.net/upload/201904/15/1555306037_701316.jpg)

？后面的参数没了 
上午还好好的  下午就不行了 不知道什么情况 其他地方相同的用法，就没问题
求大佬解惑
！！！！！！！![图片说明](https://img-ask.csdn.net/upload/201904/15/1555306153_961443.jpg)

所有的图片都是403.

所以没有办法判问题症结。