I can't delete a JSON Object Pair given a name.

WEB TMS WEB Core
1

In WebLin.JSON.pas unit, you have the following method:

function TJSONObject.RemovePair(const PairName: string): TJSONPair;
var
  o: TJSObject;
begin
  Result := nil;
  if Assigned(fjo) then
  begin
    o := fjo;
    asm
      delete o[PairName];
    end;
  end;
end;

Why do you test if fjo is assigned if it is not an object, Is a "PairName :string" what I want to remove?

2

FJO is the internal JSObject handled by TJSONObject.
"Your pair" should be there.

  TJSONObject = class(TJSONValue)
  private
    fjo: TJSObject;
3

Is not there, because I've created the JSON like this.

JSONObject := await(TJSONObject, TDataMng.DataSetToJSON(cdsCallUps));
   try
      JSONObject.RemovePair('DT_CALL_UP');
      JSONObject.AddPair('DT_CALL_UP', TTypeConv.DateTimeToJSON(cdsCallUpsDT_CALL_UP.AsDateTime));
      //await(TModalResult, MessageDlgAsync(TTypeConv.DateTimeToJSON(cdsCallUpsDT_CALL_UP.AsDateTime), mtConfirmation, [mbOk]));
      //await(TModalResult, MessageDlgAsync(JSONObject.ToString, mtConfirmation, [mbOk]));
      Request.PostData := JSONObject.ToString;

      {"CD_TEAM":"asdfasdf",
      "DT_CALL_UP":"04/23/2024",
      "DS_TEAM":"ASDFASDFff",
      "MATCH":"MATCH",
      "MEETING_POINT":"MEETING_POINT",
      "LOCATION":"LOCATION",
      "TRANSPORTATION":"TRANSPORTATION",
      "TRAVEL_BY":"TRAVEL_BY",
      "UNIFORM":"UNIFORM",
      "NOTES":"",
      "DT_CALL_UP":"04/23/2024 14:30"}

   finally
      JSONObject.Free;
   end;

You can see the resulting values in the comment.

4

Seems like it should use FMembers list when fjo is not assigned, but it doesn't.

5

Was indeed an oversight. We will have this fixed for the next update.

6

In the same sense, can you make FMembers public or create another form of traversing all pairs of a TObject?

I'm trying to create a method that copies all the members in a new TJSONObject except the one I want to substitute, but I can't traverse the complete list of members.

Do you know some tip to traverse all the pairs of a TJSONObject by his name?

7

You can use

  TJSONObject = class(TJSONValue)
  published
    property Pairs[const Index: Integer]: TJSONPair read GetPair;
    property Count: Integer read GetCount;
  end;
8

Ok. But How can I get the Name of the TJSONPair?

A pair, in origin, is a Name and its value.
But the TJSONPair don't have a property called "Name".

9

Like this?

class function TDataMng.RemoveAPair(const JSONObject :TJSONObject; PairName :string): TJSONObject;
var Pair :TJSONPair;
    i    :Integer;
begin
   Result := TJSONObject.Create;
   for i := 0 to JSONObject.Count - 1 do begin
      Pair := JSONObject.Pairs[i];
      if Pair.JsonString.Value <> PairName then begin
         Result.AddPair(Pair.JsonString.Value, Pair.JsonValue.Value);
      end;
   end;
end;
10

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11

When I use this code:

var
  jo: TJSONObject;
  i: integer;
  jp: TJSONPair;
begin
  jo := TJSONOBject.Create;
  jo.AddPair(TJSONPair.Create('Name','Joe'));
  jo.AddPair(TJSONPair.Create('City','Paris'));


  for i := 0 to jo.Count - 1 do
  begin
    jp := jo.Pairs[i];
    console.log(jp.JsonString.Value, jp.JsonValue.Value);
  end;

  jo.Free;
end;

it shows the name & value of each pair added