Question

我正在调用以下函数来在Spring Controller中执行操作。问题是alert消息不包含我发送的消息，但打印[Object object]。有没有办法发送特定的消息，根据结果，打印它还发送状态代码？

function saveButton(button) {
  var data = gatherData(button);
  $.ajax({
    type: "POST",
    url: '/editRecord',
    data: data,
    dataType: 'json',
    contentType: false,
    processData: false,
    success: function(response) {
      alert(response);
    },
    error: function(error) {
      alert(getData().done(error));
    }
  });
}

@RequestMapping(value = "/editRecord", method = RequestMethod.POST)
public @ResponseBody
String editRecord(HttpServletRequest httpRequest) 
{
  Map<String, String[]> map = httpRequest.getParameterMap();

  // do stuff

  String messageToReturn = "";
  if (userService.updateTable(pr.getUpdateQuery(fileMap))) 
  {
    messageToReturn = "Operation was successful";
  } 
  else
    messageToReturn = "Operation failed";

  return messageToReturn;
}

Answer 1

您的方法返回text（即messageToReturn）而不是JSON。您可以按如下方式生成text：

@RequestMapping(value = "/editRecord", method = RequestMethod.POST, produces="text/plain")
public @ResponseBody String editRecord(HttpServletRequest httpRequest){}

在这种情况下，从AJAX方法中删除dataType: 'json'。

但是如果你返回JSON，那么你可以用JSON格式输入它。

messageToReturn = "{\"check\":\"Operation was successful\"}"; //(without produces="text/plain")

然后像这样访问：

success: function(response) {
 console.log(response.check);
}

Answer 2

我使用Jackson库的ObjectMapper（jackson-databind）完成了它。只需修改您的方法如下：

@RequestMapping(value = "/editRecord", method = RequestMethod.POST)
public @ResponseBody
String editRecord(HttpServletRequest httpRequest) 
{
  Map<String, String[]> map = httpRequest.getParameterMap();

  // do stuff

  String messageToReturn = "";
  if (userService.updateTable(pr.getUpdateQuery(fileMap))) 
  {
    messageToReturn = "Operation was successful";
  } 
  else
    messageToReturn = "Operation failed";

  ObjectMapper mapper = new ObjectMapper();
  String json = mapper.writeValueAsString(messageToReturn);
  return json;
}

Answer 3

success: function(response) {
  alert(response.responseText);
},

Answer 4

您从弹簧控制器发送的数据可通过response.data获得。

success: function (response) {
  alert(response.data);
},
error: function (error) {
  alert(getData().done(error.data));
}

AJAX回调中的alert（）显示[Object object]

4 个答案: