How do I save a physical .json file to my C: \ drive starting from my JSONObject3 object?

procedure CreateJSON;
var
  JSONObject2, JSONObject3: TJSONObject;
  JSONValue1, JSONValue2: TJSONValue;
  JSONArray: TJSONArray;
  JSONString1, JSONString2: TJSONString;
  AText, BText: string;
  mStringStream:      TStringStream;
begin
  JSONObject2 := TJSONObject.Create;
  JSONObject3 := TJSONObject.Create;
  JSONArray := TJSONArray.Create;
  try   
    AText := 'Name';
    BText := '"Charles"';
    JSONString2 := TJSONString.Create(AText);
    JSONValue2 :=  TJSONObject.ParseJSONValue(BText);

    JSONObject2.AddPair(JSONString2, JSONValue2);   
    JSONArray.Add(JSONObject2);    
    JSONObject3.AddPair('People', JSONArray);

    mStringStream := TStringStream.Create('', TEncoding.UTF8);
    // m_StringStream.LoadFromStream(JSONObject3.ToString); <---ERROR
    mStringStream.SaveToFile('people.json');
  finally
    JSONObject3.Free;
  end;
end;

Thank you, I am a beginner with the json topic

CodePudding user response：

TJSONObject does not have any streaming support, but it does have several To...() output methods (ToBytes(), ToJSON() ToString()). The output of any of those methods can be written to a file, such as with TFile.WriteAll...() methods (WriteAllBytes(), WriteAllText()).

Try this instead:

uses
  ...,
  Data.DBXJSON, // use System.JSON in XE6 
  System.IOUtils,
  System.SysUtils;

procedure CreateJSON;
var
  JSONObject, JSONObject2: TJSONObject;
  JSONValue: TJSONValue;
  JSONArray: TJSONArray;
  AText, BText: string;
begin
  JSONObject := TJSONObject.Create;
  try   
    AText := 'Name';
    BText := '"Charles"';

    JSONValue := TJSONObject.ParseJSONValue(BText);
    if JSONValue <> nil then
    try
      JSONObject.AddPair(AText, JSONValue);
    except
      JSONValue.Free;
      raise;
    end;

    JSONArray := TJSONArray.Create;
    try
      JSONObject2 := TJSONObject.Create;
      try
        JSONArray.Add(JSONObject2);
      except
        JSONObject2.Free;
        raise;
      end;
      JSONObject.AddPair('People', JSONArray);
    except
      JSONArray.Free;
      raise;
    end;

    TFile.WriteAllText('people.json', JSONObject.ToJSON, TEncoding.UTF8);
  finally
    JSONObject.Free;
  end;
end;