mORMot Open Source

            fld := cx.NewRootedObject(cx.NewObject(nil));
 
            try
                for fldCount := 0 to FQuery.FieldCount -1 do begin
                  fldName  := LowerCase(FQuery.Fields[fldCount].FieldName);
                  fldValue := FQuery.Fields[fldCount].AsString;

                  fld.ptr.SetProperty(cx, PAnsiChar(fldName), SimpleVariantToJSval(cx,fldValue)) ;// <-------------you have chance to get AV here if garbage collector will start work
                end;

                arr.ptr.SetElement(cx, loop, fld.ptr.ToJSValue);
            finally
              cx.FreeRootedObject(fld );
            end;

consoleLog(JSON.stringify(source)); // -> {}

consoleLog(stringify(source.<propertyName>));

function <funcName>(cx: PJSContext; argc: uintN; var vp: jsargRec): Boolean; cdecl;
var arr: PJSRootedObject;
...
begin
  try
    ....
    arr := cx.NewRootedObject(cx.NewArrayObject(0));
    try
      arr.ptr.SetElement(cx, 0, SimpleVariantToJSval(cx, 'Some string'));
      arr.ptr.SetElement(cx, 1, SimpleVariantToJSval(cx, 25));
      arr.ptr.SetElement(cx, 2, SimpleVariantToJSval(cx, true));
      ...
      vp.rval := arr.ptr.ToJSValue;
    finally
      cx.FreeRootedObject(arr);
    end;
    Result := True;

  except
    on E: Exception do
    begin
      Result := False;
      vp.rval := JSVAL_VOID;
      JSError(cx, E);
    end;
  end;
end;

function <funcName>(cx: PJSContext; argc: uintN; var vp: jsargRec): Boolean; cdecl;
const arrSize = 50;
var arr: PJSRootedObject;
     arrData: Puint32Vector;
     i: integer;
     isShared: Boolean;
...
begin
  try
    ....
    arr := cx.NewRootedObject(cx.NewUint32Array(arrSize));
    try
      arrData := arr.GetUint32ArrayData(isShared, nil);
      for i := 0 to arrSize - 1 do
        arrData [i] := i*i;
      ...
      vp.rval := arr.ptr.ToJSValue;
    finally
      cx.FreeRootedObject(arr);
    end;
    Result := True;

  except
    on E: Exception do
    begin
      Result := False;
      vp.rval := JSVAL_VOID;
      JSError(cx, E);
    end;
  end;
end;

function TfrmSM45Demo.JSTestOnlyZeroAfterDecimal(cx: PJSContext; argc: uintN; var vp: JSArgRec): Boolean;
var
  dblval: Double;
begin
  try
    if (argc = 0) or  not vp.argv[0].isNumber then
      raise ESMException.Create('Expectig argument number type ');
    if vp.argv[0].isDouble then
      dblval := vp.argv[0].asDouble
    else if vp.argv[0].isInteger then
      dblval := vp.argv[0].asInteger
    else
      raise ESMException.Create('This can never happen');
    mResult.Lines.Add('########    ' + FloatToStrF(dblval, ffFixed, 20, 8) + '   ########');
    Result := True;
  except
    on E: Exception do begin
      Result := False;
      vp.rval := JSVAL_VOID;
      JSError(cx, E);
    end;
  end;
end;