//先来个例子:
procedure TForm1.FormPaint(Sender: TObject);
const
  S = '万一的 Delphi 博客';
var
  font: TFont;
begin
  font := TFont.Create;
  font.Name := '微软雅黑';
  font.Style := [fsBold, fsItalic];
  font.Color := clRed;
  font.Height := 72;

  Canvas.Font := font;
  Canvas.TextOut(10, 10, S);

  font.Free;
end;


//效果图:

//因为 Canvas 的 Font 属性就是 TFONT 类的一个实例, 所以上面的程序可以简化为:
procedure TForm1.FormPaint(Sender: TObject);
const
  S = '万一的 Delphi 博客';
begin
  Canvas.Font.Name := '微软雅黑';
  Canvas.Font.Style := [fsBold, fsItalic];
  Canvas.Font.Color := clRed;
  Canvas.Font.Height := 72;

  Canvas.TextOut(10, 10, S);
end;

//TFont 类的常用属性:

{Name: 字体名称}

{Color: 颜色}

{Size、Height: 字号与字体高度, 都可以设定字体大小}

{Style: 字体样式; 是个集合值, 是下面可选值或它们的组合:}
fsBold
fsItalic
fsUnderline
fsStrikeOut

{Pitch: 是字间距相关的, 有三个枚举值可选(不过我没测试出效果):}
fpDefault
fpVariable
fpFixed

{Charset: 字符集, 是个整数, 可能的值有:}
ANSI_CHARSET        = 0;
DEFAULT_CHARSET     = 1;
SYMBOL_CHARSET      = 2;
SHIFTJIS_CHARSET    = 128;
HANGEUL_CHARSET     = 129;
GB2312_CHARSET      = 134;
CHINESEBIG5_CHARSET = 136;
OEM_CHARSET         = 255;
JOHAB_CHARSET       = 130;
HEBREW_CHARSET      = 177;
ARABIC_CHARSET      = 178;
GREEK_CHARSET       = 161;
TURKISH_CHARSET     = 162;
VIETNAMESE_CHARSET  = 163;
THAI_CHARSET        = 222;
EASTEUROPE_CHARSET  = 238;
RUSSIAN_CHARSET     = 204;

{Orientation: 旋转角度, 单位是 1/10 度, 举个例子:}

//代码:
const
  S = '万一的 Delphi 博客';
begin
  Canvas.Font.Style := [fsBold];
  Canvas.Font.Color := clRed;
  Canvas.Font.Height := 32;

  Canvas.Font.Orientation := 450;
  Canvas.TextOut(0, ClientHeight-20, S);
end;


//效果图: