Question

请查看此代码。我希望它能够：

执行保存两个值的{ajax（latitude和longitude）
在这里使用这些值= var center = new google.maps.LatLng(resplat, resplon);

问题是代码没有按此顺序执行。它“跳过”最初的Ajax并在运行其他代码时首先返回它。这使我的两个价值观无用。有人可以解释代码执行顺序背后的逻辑吗？

 function Initialize() {
     $.ajax({
         type: "GET",
         url: 'http://ip-api.com/json',
         dataType: "json",
         success: function (resp) {
             resplat = resp.lat;
             resplon = resp.lon;
         }
     });
     // Google has tweaked their interface somewhat - this tells the api to use that new UI
     google.maps.visualRefresh = true;
     var center = new google.maps.LatLng(resplat, resplon);

     // These are options that set initial zoom level, where the map is centered globally to start, and the type of map to show
     var mapOptions = {
         zoom: 15,
         center: center,
         mapTypeId: google.maps.MapTypeId.G_NORMAL_MAP
     };

Answer 1

移动使用ajax成功回调中的resplat和resplon 的代码：

function Initialize() {
      $.ajax({
          type: "GET",
          url: 'http://ip-api.com/json',
          dataType: "json",
          success: function (resp) {
              var resplat = resp.lat;
              var resplon = resp.lon;

              // Google has tweaked their interface somewhat - this tells the api to use that new UI
             google.maps.visualRefresh = true;
             var center = new google.maps.LatLng(resplat, resplon);

             // These are options that set initial zoom level, where the map is centered globally to start, and the type of map to show
             var mapOptions = {
                  zoom: 15,
                 center: center,
                 mapTypeId: google.maps.MapTypeId.G_NORMAL_MAP
             };
         }
      });
}

$.ajax是异步调用。您必须等待，直到数据到来（success处理程序）。然后你可以使用它。

另一种方法是添加.done(foo)处理程序：

$.ajax({...}).done(function (...) { /* do something */ });

Jquery以奇怪的顺序执行

1 个答案: