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我已经声明了这些新类型:

type
 TRacer = record
  name: string;
  win, tie, loss, points: integer;
 end;

 TRacersList = TList<TRacer>;

我在数据模块中有一个如下所示的过程:

procedure DMConnection.getDivision(aList: TRacersList; const game, id: string);
begin

 //1) setup the REST params
 RESTRequest.Params[0].Value := game;
 RESTRequest.Params[1].Value := id;

 //2) execute async so UI won't freeze
 RESTRequest.ExecuteAsync(procedure
 var tmp: TRacer;
    ja: TJSONArray;
    jv: TJSONValue;
 begin

  //parse the JSON. The RESTResponse is a TRESTResponse that holds the result of the RESTRequest. I have made a test inside the component (right click -> execute) and it works properly (= I can see the JSON inside the Content property).
  ja := TJSONObject.ParseJSONValue(RESTResponse.Content) as TJSONArray;

  for jv in ja do begin
   tmp.name := jv.GetValue<string>('name');
   tmp.win := jv.GetValue<integer>('Wins');
   tmp.tie := jv.GetValue<integer>('Ties');
   tmp.loss := jv.GetValue<integer>('Loss');
   tmp.points := jv.GetValue<integer>('Pts');

   aList.Add(tmp);
  end;

 end);

end;

如果您想知道,这是 JSON 字符串:

[{"name":"payer1","Wins":"1","Ties":"0","Loss":"0","Pts":"3"},{"name":"Velocity","Wins":"0","Ties":"0","Loss":"1","Pts":"0"},{"name":"test2","Wins":"0","Ties":"0","Loss":"0","Pts":"0"}]

在主窗体中,我可以通过这种方式调用该过程:

DMConnection.getDivision(myList, 'mku', 'k2');

我有以下问题。该变量myList: TRacersList在表单的 OnCreate 和 OnDestroy 事件中创建和释放。如果您尝试运行此代码:

DMConnection.getDivision(myList, 'mku', 'k2');
ShowMessage(myList.Count.toString);

结果为 0。相反,如果我将异步请求放在aList.Add(tmp); 外部(例如,在参数设置之前),则计数为 1。

这意味着当列表在完成处理程序之外时正在填充列表,ExecuteAsync但当列表在内部时则不会。任何想法?

我已经确认默认情况下同步设置为 True,所以添加

TTHread.Synchronize(nil, procedure
begin
 aList.Add(tmp);
end)

将是无用的。我应该怎么办?我想在数据模块中有这个解析/休息的东西,这样我就可以把互联网的东西与我的应用程序实现分开。

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