Hostanwendung für gegebenen Dateityp bestimmen

[paritycheck]

Könnte damit klappen

Delphi-Quellcode:

function FindExecutableA(lpFile: PChar; lpDirectory: PChar; lpResult: PChar): Cardinal; stdcall; external 'shell32.dll' name 'FindExecutableA';

function GetExeFromDocument(const Document: String; const Directory: String): String;
var
  ret: array[0..MAX_PATH-1] of char;
  lpFile,
  lpDirectory: PChar;
begin
  result:= '';
  ZeroMemory(@ret, MAX_PATH);
  lpFile:= PChar(Document);
  lpDirectory:= PChar(Directory);
  if FindExecutableA(lpFile, lpDirectory, @ret[0]) > 32 then
     Result:= ret;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  Showmessage(GetExeFromDocument('a.txt', 'D:\Temp'));
end;