Delphi 的绘图功能[13] TBrush 类

//画刷类 TBrush 有三个重要属性: Color、Style、Bitmap.

{Style: 样式; Delphi 为画刷定义了样式枚举 TBrushStyle, 包含以下样式:}
bsSolid
bsClear
bsHorizontal
bsVertical
bsFDiagonal
bsBDiagonal
bsCross
bsDiagCross


//下面小程序展示了上面的其中填充样式:
var
  i,n: Integer;
  r: TRect;
begin
  Canvas.Pen.Color := clRed;
  Canvas.Pen.Width := 1;

  n := 10;
  for i := 0 to 7 do
  begin
    Canvas.Brush.Color := clYellow;
    Canvas.Brush.Style := TBrushStyle(i);
    r := Rect(n, 10, n+36, ClientHeight-10);
    Canvas.FillRect(r);
    Canvas.Rectangle(r);
    n := n + 48;
  end;
end;


//效果图:

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//使用画刷的 Bitmap 属性则可以使用图片填充.

procedure TForm1.FormClick(Sender: TObject);
var
  bit: TBitmap;
begin
  bit := TBitmap.Create;
  bit.LoadFromFile('c:\temp\bg.bmp');
  Canvas.Brush.Bitmap := bit;
  Canvas.Ellipse(0, 0, ClientWidth, ClientHeight);
  bit.Free;
end;


//效果图:

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