Superobject

[Ryzinski]

Hello!

Is there a more native way to do this in XE3? Without the superobject library?

Delphi-Quellcode:

unit Unit4;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs,superobject, Vcl.StdCtrls;

type
  TForm4 = class(TForm)
    Button1: TButton;
  procedure TestMethod(value,test: string);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form4: TForm4;

implementation

{$R *.dfm}
procedure TForm4.Button1Click(Sender: TObject);
begin
Label1.Caption:=SOInvoke(Self, 'TestMethod', SO('{value: "hello",test: "hello"}')).AsString;
end;

procedure TForm4.TestMethod(value,test: string);
begin
  Caption := value;
  Button1.Caption:=test;
  result:='blabla';
end;
end.

[Sir Rufo]

Maybe its a good advice to have a close look at the sources (superobject.pas)

[himitsu]

- '{value: "hello", test: "hello"}' represents a JSON string

- convert JSONString to JSONObject

- convert values of JSONObject to array of TValue

- TRttiMethod.Invoke to call the method

untested code:

Delphi-Quellcode:

uses System.RTTI, Data.DBXJSON, Data.DBXJSONReflect;

type
  TJSONUnMarshal2 = class(TJSONUnMarshal);  // hack for protected JSONToTValue

var
  MethodName, ParamStr: string;
  Method: TRttiMethod;
  MethodParams: TArray<TRttiParameter>;
  JSONValues: TJSONValue;
  JSONPair: TJSONPair;
  JSONConvert: TJSONUnMarshal2;
  Values: TArray<TValue>;
  i: Integer;
begin
  MethodName := 'TestMethod';
  ParamStr := '{value: "hello", test: "hello"}';  // '{}' if none Parameters exists

  Method := TRttiContext.Create.GetType(Self.ClassType).GetMethod(MethodName);
  if not Assigned(Method) then
    raise Exception.CreateFmt('Method "%s" does not exists.', [MethodName]);
  MethodParams := Method.GetParameters;

  JSONValues := TJSONObject.ParseJSONValue(ParamStr);
  if not (JSONValues is TJSONObject) then
    raise Exception.CreateFmt('Invalid Parameters for Method "%s".', [MethodName]);
  if TJSONObject(JSONValues).Size <> Length(MethodParams) then
    raise Exception.CreateFmt('Invalid Parameter-Count for Method "%s".', [MethodName]);
  JSONConvert := TJSONUnMarshal2(TJSONConverters.GetJSONUnMarshaler);
  SetLength(Values, TJSONObject(JSONValues).Size);
  for i := 0 to High(Values) do begin
    JSONPair := TJSONObject(JSONValues).Get(i);
    if not SameText(JSONPair.JsonString.Value, MethodParams[i].Name) then
      raise Exception.CreateFmt('Invalid Parameter "%s" for Method "%s".', [MethodParams[i].Name, MethodName]);
    Values[i] := JSONConvert.JSONToTValue(JSONPair.JsonValue, MethodParams[i].ParamType);
  end;

  Result := Method.Invoke(Self, Values).AsString;
end;