var

  MainForm: TclForm;

void TestUpdateJsonValue;

var

  OrderListArrRef: TCLJSONArray;

  ExistingItem: TCLJSONObject;

  J, TargetItemID, NewAmount, FoundIndex: Integer;

{

  try

    // 1. Setup: Create a sample JSON Array

    OrderListArrRef = TCLJSONArray.CreateFromJSON('[{"item_id": 27, "amount": 4}, {"item_id": 13, "amount": 1}]');

    // 2. Define Test Data

    TargetItemID = 27;  // We want to change item 27

    NewAmount = 99;     // We want to change amount from 4 to 99

    FoundIndex = -1;

    ShowMessage('Before Update: ' + OrderListArrRef.ToJSONString);

    // 3. Logic: Loop to find and update

    for (J = 0 to OrderListArrRef.Count - 1)

    {

      ShowMessage('TCLJSONValue: '+OrderListArrRef.GetItem(J).ToString);//GetItem Returns TCLJSONValue

      ExistingItem = TCLJSON.ParseToJsonObject(OrderListArrRef.GetItem(J).ToString);

      // Check if IDs match

      if (ExistingItem.GetValue('item_id').AsInteger == TargetItemID )

      {

        // --- First Remove After AddPair ---

        ShowMessage('ExistingItem before changing amount: '+ExistingItem.ToJSONString)

        //ExistingItem.RemovePair('amount');                  // Remove old value

        //ExistingItem.AddPair('amount', TCLJSONValue.Int(NewAmount)); // Add new value

        // ---------------------

        // SetValue Clause

        //ShowMessage(ExistingItem.ToJsonString)

        ExistingItem.SetValue('amount', TCLJSONValue.Int(NewAmount)); // Add new value

        ShowMessage('ExistingItem: '+ExistingItem.ToJSONString)

        OrderListArrRef.Remove(J);

        OrderListArrRef.AddObject(ExistingItem);

        FoundIndex = J;

        Break; // Optimization: Stop once found

      }

    }

    // 4. Verification

    if (FoundIndex > -1 )

      ShowMessage('After Update:  ' + OrderListArrRef.ToJSONString)

    else

      ShowMessage('Error: Item ID ' + IntToStr(TargetItemID) + ' not found.');

  except

    ShowMessage('Exception: ' + LastExceptionMessage);

  }

}

{

  MainForm = TclForm.Create(Self);

  TestUpdateJsonValue; // Run the test

  MainForm.Run;

}