Delphi程序开启XP的ClearType显示效果

微软雅黑字体在没有开启ClearType效果时显示会一塌糊涂,最近项目中因使用了雅黑字体,所以系统启动时候需要自动开启这个功能.

网上大部份资料都是针对注册表的,几乎没有什么用.

相关位置:HKEY_CURRENT_USER\Control Panel\Desktop

类似如下:

if NOT reg.ValueExists('FontSmoothing') then reg.WriteString('FontSmoothing','2');

if NOT reg.ValueExists('FontSmoothingType') then reg.WriteInteger('FontSmoothingType',2);

下面的方法是通过调用SystemParametersInfo来实现:98和2000没有ClearType的功能

使用方法:

Font smoothing is handled by the OS, but can be controlled via the SystemParametersInfo API. Please note that the smoothing type does not apply to Win2K, only XP and above.

// Example usage

const

FE_FONTSMOOTHINGSTANDARD   = $00000001;

FE_FONTSMOOTHINGCLEARTYPE = $00000002;

SPI_GETFONTSMOOTHINGTYPE   = $0000200A;

SPI_SETFONTSMOOTHINGTYPE   = $0000200B;

procedure TForm1.Button1Click(Sender: TObject);

var dwType:        DWORD;

     bIsSet:        BOOL;

begin

if SystemParametersInfo(SPI_GETFONTSMOOTHING, 0, @bIsSet, 0) then

begin

     if bIsSet then

     begin

        ShowMessage('Font smoothing is applied');

        if SystemParametersInfo(SPI_GETFONTSMOOTHINGTYPE, 0, @dwType, 0) then

        begin

           case dwType of

              FE_FONTSMOOTHINGSTANDARD   : ShowMessage('Smoothing type is standard');

              FE_FONTSMOOTHINGCLEARTYPE : ShowMessage('Smoothing type is clear type');

           end;

        end;

     end

     else

        ShowMessage('Font smoothing not is applied');

end;

// Enable clear type font smoothing

SystemParametersInfo(SPI_SETFONTSMOOTHING, 1, nil, SPIF_UPDATEINIFILE or SPIF_SENDCHANGE);

SystemParametersInfo(SPI_SETFONTSMOOTHINGTYPE, 0, Pointer(FE_FONTSMOOTHINGCLEARTYPE), SPIF_UPDATEINIFILE or SPIF_SENDCHANGE);

// Disable font smoothing

SystemParametersInfo(SPI_SETFONTSMOOTHING, 0, nil, SPIF_UPDATEINIFILE or SPIF_SENDCHANGE);

end;