屏幕亮度(XE10.1+WIN8.164)

相关资料：

http://bbs.csdn.net/topics/390664310

实例代码：

 unit Unit1;

 interface

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

 type
   TRampArray = array[..] of array[byte] of word;

 type
   TForm1 = class(TForm)
     Button1: TButton;
     Button2: TButton;
     Image1: TImage;
     procedure Button1Click(Sender: TObject);
     procedure FormCreate(Sender: TObject);
     procedure Button2Click(Sender: TObject);
     procedure FormDestroy(Sender: TObject);
   private
     { Private declarations }
   public
     { Public declarations }
   end;

 var
   Form1: TForm1;
   origRampArray: TRampArray;

 implementation

 {$R *.dfm}

 function SetBrightness(wBrightness: word): boolean;
 var
   RampArray: TRampArray;
   I, Value: integer;
   DC: HDC;
 begin
   for I :=  to MAXBYTE do
   begin
     Value := I * (wBrightness + );
     if (Value > MAXWORD) then Value := MAXWORD;
     RampArray[][I] := Value;
     RampArray[][I] := Value;
     RampArray[][I] := Value;
   end;
   DC := GetDC();
   try
     Result := SetDeviceGammaRamp(DC, RampArray);
   finally
     ReleaseDC(, DC);
   end;
 end;

 procedure TForm1.Button1Click(Sender: TObject);
 begin
   SetBrightness();
 end;

 procedure TForm1.Button2Click(Sender: TObject);
 var
   DC: HDC;
 begin
   DC := GetDC();
   try
     SetDeviceGammaRamp(DC, origRampArray);
   finally
     ReleaseDC(, DC);
   end
 end;

 procedure TForm1.FormCreate(Sender: TObject);
 var
   DC: HDC;
 begin
   DC := GetDC();
   try
     GetDeviceGammaRamp(DC, origRampArray);
   finally
     ReleaseDC(, DC);
   end
 end;

 procedure TForm1.FormDestroy(Sender: TObject);
 begin
   Button2Click(Button2);
 end;

 end.