function GetRegistryString(const RootKey: Windows.HKEY;
  const SubKey, Name: string): string;
var
  Reg: Registry.TRegistry;          // registry access object
  ValueInfo: Registry.TRegDataInfo; // info about registry value
begin
  Result := '';
  // Open registry at required root key
  Reg := Registry.TRegistry.Create;
  try
    Reg.RootKey := RootKey;
    // Open registry key and check value exists
    if Reg.OpenKeyReadOnly(SubKey)
      and Reg.ValueExists(Name) then
    begin
      // Check if registry value is string or integer
      Reg.GetDataInfo(Name, ValueInfo);
      case ValueInfo.RegData of
        Registry.rdString, Registry.rdExpandString:
          // string value: just return it
          Result := Reg.ReadString(Name);
        Registry.rdInteger:
          // integer value: convert to string
          Result := SysUtils.IntToStr(Reg.ReadInteger(Name));
        else
          // unsupported value: raise exception
          raise SysUtils.Exception.Create(
            'Unsupported registry type'
          );
      end;
    end;
  finally
    // Close registry
    Reg.Free;
  end;
end;
//delphi/2292