Dephi 屏蔽进程声音

常用于 WebBrowser控件后台打开网页时，需要屏蔽网页的视频声音

function DSoundsCode():Integer ;stdcall;
var
  hDSound: Cardinal;
  pDirectSoundCreate: Pointer;
  lp: Cardinal;
begin
  if Win32MajorVersion >= 6 then //Vista以上的操作系统
  begin
    Result := Integer(ControlVolume.SetVolumeMute(Master,True));
    Exit;
  end;    
  hDSound := GetModuleHandle('DSound.dll');
  if hDSound = 0 then hDSound := LoadLibrary('DSound.dll');
  if hDSound > 0 then
  begin
    pDirectSoundCreate := GetProcAddress(hDSound, 'DirectSoundCreate');
    if Assigned(pDirectSoundCreate) then
    begin
      VirtualProtect(pDirectSoundCreate, 3, PAGE_EXECUTE_READWRITE, lp);
      Move(#$C2#$0C#$00, pDirectSoundCreate^, 3);
    end;
  end;  


  hDSound := GetModuleHandle('Winmm.dll');
  if hDSound = 0 then hDSound := LoadLibrary('Winmm.dll');
  if hDSound > 0 then
  begin
    pDirectSoundCreate := GetProcAddress(hDSound, 'midiStreamOpen');
    if Assigned(pDirectSoundCreate) then
    begin
      VirtualProtect(pDirectSoundCreate, 3, PAGE_EXECUTE_READWRITE, lp);
      Move(#$C2#$04#$00, pDirectSoundCreate^, 3);
    end;
    pDirectSoundCreate := GetProcAddress(hDSound, 'waveOutWrite');
    if Assigned(pDirectSoundCreate) then
    begin
      VirtualProtect(pDirectSoundCreate, 3, PAGE_EXECUTE_READWRITE, lp);
      Move(#$C2#$0C#$00, pDirectSoundCreate^, 3);
    end;
  end;
  Result := 1597;
end;