MDI窗体的问题,每点击一次按钮就创建一个窗体,我只想创建一个窗体,不能重复,怎么判断窗体已体创建
procedure TForm1.Button1Click(Sender: TObject);
begin
Application.CreateForm(TForm2, Form2);
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
Application.CreateForm(TForm2, Form2);
end;
Form2 := TForm2.Create(Application);
form2.show;
procedure TForm1.Button1Click(Sender: TObject);
begin
if not assigned(form2) then
begin
Form2 := TForm2.Create(Application);
end;
end;
end.
procedure TForm2.FormClose(Sender: TObject; var Action: TCloseAction);
begin
action:=cafree;
end;当关闭FORM2后,怎么打不开了啊