//以下程序是用来做像windows的开始菜单,可是为什么会在下面的
//rect(0,0,mbitmap.Width,mbitmap.Height);这一句出现raised exception异常
//把mbitmap.Width和mbitmap.Height改成数字这句话就通过了,没有异常unit Unit1;interfaceuses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, Menus, ExtCtrls, jpeg;type
TForm1 = class(TForm)
MainMenu1: TMainMenu;
N1: TMenuItem;
N2: TMenuItem;
N3: TMenuItem;
N4: TMenuItem;
N5: TMenuItem;
N6: TMenuItem;
Image1: TImage;
procedure FormCreate(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
procedure N4AdvancedDrawItem(Sender: TObject; ACanvas: TCanvas;
ARect: TRect; State: TOwnerDrawState);
procedure N5Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;var
Form1: TForm1;
Mbitmap:Tbitmap;
implementation{$R *.dfm}procedure TForm1.FormCreate(Sender: TObject);
begin
Mbitmap:=Tbitmap.Create;
mbitmap.LoadFromFile('2.bmp');
end;procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
mbitmap.Free;
end;procedure TForm1.N4AdvancedDrawItem(Sender: TObject; ACanvas: TCanvas;
ARect: TRect; State: TOwnerDrawState);
var
Mrect:Trect;
begin
acanvas.TextWidth(TMenuItem(Sender).Caption);
mrect:= rect(0,0,mbitmap.Width,mbitmap.Height);//出现异常
acanvas.Draw(arect.Left,arect.Top-arect.Bottom,mbitmap);
acanvas.TextRect(rect(arect.Left+mbitmap.Width+2,arect.Top,arect.Right,arect.Bottom),arect.Left+mbitmap.Width+2,arect.Top+3,TMenuItem(Sender).Caption);
setbkmode(acanvas.Handle,TRANSPARENT);
DrawText(acanvas.Handle,'我'+#13+'的'+#13+'菜'+#13+'单',-1,mrect,DT_LEFT+DT_Center);
end;procedure TForm1.N5Click(Sender: TObject);
begin
Close;
end;end.
//rect(0,0,mbitmap.Width,mbitmap.Height);这一句出现raised exception异常
//把mbitmap.Width和mbitmap.Height改成数字这句话就通过了,没有异常unit Unit1;interfaceuses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, Menus, ExtCtrls, jpeg;type
TForm1 = class(TForm)
MainMenu1: TMainMenu;
N1: TMenuItem;
N2: TMenuItem;
N3: TMenuItem;
N4: TMenuItem;
N5: TMenuItem;
N6: TMenuItem;
Image1: TImage;
procedure FormCreate(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
procedure N4AdvancedDrawItem(Sender: TObject; ACanvas: TCanvas;
ARect: TRect; State: TOwnerDrawState);
procedure N5Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;var
Form1: TForm1;
Mbitmap:Tbitmap;
implementation{$R *.dfm}procedure TForm1.FormCreate(Sender: TObject);
begin
Mbitmap:=Tbitmap.Create;
mbitmap.LoadFromFile('2.bmp');
end;procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
mbitmap.Free;
end;procedure TForm1.N4AdvancedDrawItem(Sender: TObject; ACanvas: TCanvas;
ARect: TRect; State: TOwnerDrawState);
var
Mrect:Trect;
begin
acanvas.TextWidth(TMenuItem(Sender).Caption);
mrect:= rect(0,0,mbitmap.Width,mbitmap.Height);//出现异常
acanvas.Draw(arect.Left,arect.Top-arect.Bottom,mbitmap);
acanvas.TextRect(rect(arect.Left+mbitmap.Width+2,arect.Top,arect.Right,arect.Bottom),arect.Left+mbitmap.Width+2,arect.Top+3,TMenuItem(Sender).Caption);
setbkmode(acanvas.Handle,TRANSPARENT);
DrawText(acanvas.Handle,'我'+#13+'的'+#13+'菜'+#13+'单',-1,mrect,DT_LEFT+DT_Center);
end;procedure TForm1.N5Click(Sender: TObject);
begin
Close;
end;end.
先把那些值赋给变量,再用mrect:= rect(0,0,mbitmap.Width,mbitmap.Height);这里用被赋值的变量试试.