贴出主窗体增强复用性 源代码 各位再帮我修改、修改

Question

主窗体form1:
unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;type
  Tfrm=class of TForm;
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    procedure Showfrm(Frmclass:Tfrm; FrmValue:TForm);
  end;var
  Form1: TForm1;implementation
     uses unit2,unit3,unit4;
   const
      ArrFrm:array[0..2] of Tfrm=(Tform2,Tform3,Tform4);
{$R *.dfm}
procedure TForm1.Showfrm(Frmclass:Tfrm; FrmValue:TForm);  
begin
      if assigned(FrmValue) then
                begin
               showmessage('存在');
               FrmValue.ShowModal;
                  end
               else
               begin
      FrmValue:=Frmclass.Create(application);
      try
      FrmValue.Showmodal;
      finally
         FrmValue.Free;   (1)
         FrmValue:=nil;   (2)
      end;
      end;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
showfrm(Tfrm(ArrFrm[0]),form2);             //问题是怎么把form2,form3,form4用数组来调用
end;                                        end.   (1)与(2)调换一下才不会出现:FrmValue从来没有使用的delphi编译器的提示，但能顺利执行.

Answer 1

恩 思路還可以。。
showfrm(Tfrm(ArrFrm[0]),form2);             //问题是怎么把form2,form3,form4用数
你可以再定義一個數組 保存form2.form3..與 
ArrFrm:array[0..2] of Tfrm=(Tform2,Tform3,Tform4);中類型要一一對應 不然會出錯的。

Answer 2

beyondtkl(大龙驹)老师:   我正是想把引用变量 form2、form3、form4用数组来表示。因为这样，我可以不理会以后的一些变动，只调换枚举值，不知道怎么写?

Answer 3

直接用一个就行了，没必要用数组了，反正你用完了就释放了type
  Tfrm=class of TForm;
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    procedure Showfrm(FrmClass:TFrm;FrmValue: TForm);
  end;var
  Form1: TForm1;
  VarForm:Tform;Const
  ArrFrm:array[0..2] of Tfrm=(Tform2,Tform3,Tform4);implementation{$R *.dfm}{ TForm1 }procedure TForm1.Showfrm(FrmClass:TFrm;FrmValue: TForm);
begin
   if assigned(FrmValue) then
   begin
     showmessage('´æÔÚ');
     FrmValue.ShowModal;
   end
   else
     begin
      FrmValue:=FrmClass.Create(application);
      try
        FrmValue.Showmodal;
      finally
         Freeandnil(FrmValue);
     end;
   end;
end;procedure TForm1.Button1Click(Sender: TObject);
begin
  showfrm(ArrFrm[0],VarForm);
end;

Answer 4

俺又修改的:主窗体form1:
unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;type
  Tfrm=class of TForm;
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    procedure Showfrm(Frmclass:Tfrm; FrmValue:TForm);
  end;var
  Form1: TForm1;implementation
     uses unit2,unit3,unit4;
   const
      ArrFrm:array[0..2] of Tfrm=(Tform2,Tform3,Tform4);
{$R *.dfm}
procedure TForm1.Showfrm(Frmclass:Tfrm; FrmValue:TForm);  
begin
   if not  assigned(FrmValue) then
      FrmValue:=Frmclass.Create(application);
      try
      FrmValue.Showmodal;
      finally
    
         FreeAndNil(FrmValu);
      end;
      end;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
showfrm(Tfrm(ArrFrm[0]),form2);             //问题是怎么把form2,form3,form4用数组来调用
end;                                        end.