Question

我希望我的函数（对控制器执行ajax调用）从响应中返回消息。

我试过这个，但它不起作用。如何才能达到我的目标？对此有更好的解决方案吗？

var exists = personExists ();

   if (exists != null) {
      alert('The person already exists');
      return;
   }

var personExists = function () {

   var exists = false;
   var errorMsg = null;

$.ajax({
      url: "@Url.Action("PersonExist", "Person")",
      type: "POST",
      dataType: 'json',
      data: { name: self.name(), socialSecurityNumber: self.socialSecurityNumber() },
      async: false,
      contentType: "application/json",
      success: function (response) {
          if (response.exists) {
             exists = true;
             errorMsg = response.message;
          }
      }
 });

 if (exists)
   return errorMsg;

 return null;
};

Answer 1

您需要使用回调：

function getErrorMessage(message) {
    //do whatever
}

在AJAX请求中：

$.ajax({
  url: "@Url.Action("PersonExist", "Person")",
  type: "POST",
  dataType: 'json',
  data: { name: self.name(), socialSecurityNumber: self.socialSecurityNumber() },
  async: false,
  contentType: "application/json",
  success: function (response) {
      if (response.exists) {
         exists = true;
         getErrorMessage(response.message); //callback
      }
  }

}）;

Answer 2

您可以使用回调函数执行此操作;

var personExists = function (callback) {

   var exists = false;
   var errorMsg = null;

    $.ajax({
          url: "@Url.Action("PersonExist", "Person")",
          type: "POST",
          dataType: 'json',
          data: { name: self.name(), socialSecurityNumber: self.socialSecurityNumber() },
          async: false,
          contentType: "application/json",
          success: function (response) {
              if (response.exists) {
                 exists = true;
                 errorMsg = response.message;
                 callback(exists, errorMsg);
              }
          }
     });

     if (exists)
       return errorMsg;

     return null;
};

和用法;

personExists(function(exists, err) {
    if (exists != null) {
      alert('The person already exists');
      return;
   }    
});

简单地说，您可以将exists和errorMsg传递给回调。有关回调函数

的更多详细信息，请参阅here

函数不从ajax调用返回消息

2 个答案: