各位 先進/高手 大家好,小弟又來 問 問題了  src="http://delphi.ktop.com.tw/loadfile.php?TOPICID=11872729&CC=265531"> < >< >

試試看 :

type
  DumClass = class(TCustomGrid);
  TForm1 = class(TForm)
    Table1: TTable;
    DataSource1: TDataSource;
    DBGrid1: TDBGrid;
    StatusBar1: TStatusBar;
    procedure DBGrid1MouseMove(Sender: TObject; Shift: TShiftState; X,
      Y: Integer);
    procedure DBGrid1MouseUp(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
  private
    SelectRect : TRect;
    CG : TGridCoord;
    { Private declarations }
  public
    { Public declarations }
  end;    var
  Form1: TForm1;    implementation    {$R *.dfm}    procedure TForm1.DBGrid1MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
var MG : TGridCoord;
    ColChanged : Boolean;
    Sum : real;
begin
  if SSLeft in Shift then begin
     MG := DBGrid1.MouseCoord(X,Y);
     ColChanged := (MG.X<>CG.X) or (CG.X = 0);
     if ColChanged then begin
       if CG.Y=0 then CG.Y:=MG.Y;
       SelectRect :=DumClass(DBGrid1).CellRect(MG.X,CG.Y);
       DBGrid1.Canvas.Brush.Color := clRed;
       DBGrid1.Canvas.FrameRect(SelectRect);
       if StatusBar1.Panels[0].Text='' then Sum := 0
       else Sum := StrtoFloat(StatusBar1.Panels[0].Text);
       StatusBar1.Panels[0].Text := FloatToStr(sum 
            strtofloat(DumClass(DBGrid1).GetEditText(MG.X,CG.Y)));
       CG.X := MG.X;
     end;
  end;
end;    procedure TForm1.DBGrid1MouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
begin
  DBGrid1.Invalidate;
  CG.X := 0;
  CG.Y := 0;
  StatusBar1.Panels[0].Text := '0';
end;

發表人 - Mickey 於 2003/09/25 19:53:33

感謝 Mickey 版主的 回覆,終於可以動了耶!! 真是太感謝了!!< >< > 不過 如果 我要 加總的欄位有空值就會出現如下訊息 這該如何解決啊?? 原諒小弟才疏學淺,也感謝 Mickey 版主的解答!!

多一個 if 或用 try except 阿...這...有點誇張了喔....

var inc : real;
begin
...
       if StatusBar1.Panels[0].Text='' then Sum := 0
       else Sum := StrtoFloat(StatusBar1.Panels[0].Text);
       try
         inc := strtofloat(DumClass(DBGrid1).GetEditText(MG.X,CG.Y));
       except
         inc := 0;
       end;
       StatusBar1.Panels[0].Text := FloatToStr(sum inc);
       

感謝 Mickey 版主的回覆,解決我的問題了!! 真是 感謝 !!

引言: 多一個 if 或用 try except 阿...這...有點誇張了喔....

var inc : real;
begin
...
       if StatusBar1.Panels[0].Text='' then Sum := 0
       else Sum := StrtoFloat(StatusBar1.Panels[0].Text);
       try
         inc := strtofloat(DumClass(DBGrid1).GetEditText(MG.X,CG.Y));
       except
         inc := 0;
       end;
       StatusBar1.Panels[0].Text := FloatToStr(sum inc);
       

用strtofloatdef(StatusBar1.Panels[0].Text,0)更方便喔 ～～～Delphi K.Top討論區站長～～～

謝謝天使...< >又學到了...< >

感謝 領航天使 & Mickey 兩位版主的耐心教導!!  < >< >< > 因為使用拖曳滑鼠,會有無法跨頁(無法拖曳過去) 能否改為使用按 >< >

被點名了... 舉一隅, 至少也一隅返吧...加油 ! 不過呢...送佛送到西...阿彌陀佛 :

unit Unit1;    interface    uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ComCtrls, Grids, DBGrids, DB, DBTables, Math;    type
  DumClass = class(TCustomGrid);
  TForm1 = class(TForm)
    Table1: TTable;
    DataSource1: TDataSource;
    DBGrid1: TDBGrid;
    StatusBar1: TStatusBar;
    procedure DBGrid1KeyDown(Sender: TObject; var Key: Word;
      Shift: TShiftState);
    procedure DBGrid1KeyUp(Sender: TObject; var Key: Word;
      Shift: TShiftState);
  private
    { Private declarations }
    SelectRect : TRect;
    CG : TGridCoord;
    Selecting : Boolean;
  public
    { Public declarations }
  end;    var
  Form1: TForm1;    implementation    {$R *.dfm}    procedure TForm1.DBGrid1KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
var C,D : TRect;
begin
  if (ssShift in Shift) then begin
    if (not Selecting) then begin
      CG.X := DumClass(DBGrid1).Col;
      CG.Y := DumClass(DBGrid1).Row;
      Selecting := True;
      StatusBar1.Panels[0].Text := 'Selecting...';
    end;
    C := DumClass(DBGrid1).CellRect(CG.X,CG.Y);
    D := DumClass(DBGrid1).CellRect(DumClass(DBGrid1).Col,DumClass(DBGrid1).Row);
    SelectRect.Left := min(C.Left,D.Left);
    SelectRect.Right := max(C.Right,D.Right);
    SelectRect.Top := C.Top;
    SelectRect.Bottom := C.Bottom;
    DBGrid1.Canvas.Brush.Color := clRed;
    DBGrid1.Canvas.FrameRect(SelectRect);
  end;
end;    procedure TForm1.DBGrid1KeyUp(Sender: TObject; var Key: Word;
  Shift: TShiftState);
var i : integer;
    Sum : real;
begin
  if (Shift=[])and(key=16)and(Selecting) then begin
    sum := 0;
    for i := min(CG.X, DumClass(DBGrid1).Col) to
             max(CG.X, DumClass(DBGrid1).Col) do
      sum := sum  strtofloatdef(DumClass(DBGrid1).GetEditText(i,CG.Y),0);
    StatusBar1.Panels[0].Text := FloatToStr(sum);
    Selecting := False;
    DBGrid1.Invalidate;
  end;
end;    end.

感謝 Mickey 兄,真是麻煩 你不少    < >< > 我會多加油的 !! THANKS!!!

對不起...我口吻稍嫌嚴厲了一些...    只是希望一個問題除了獲得解決之外,    問答雙方都能有所收穫, 而非單純"解決"問題...    此篇的重點在於 Class 的繼承與運用, 希望你    "解決"問題後, 能進一步了解這些觀念, 未來    若遇到類似的問題, 就能游刃有餘...

不會啦!! 我真的 很感激 有這塊園地 更感謝 Mickey 兄的 傳授!! 其實 我這一系列的問題,都是在模擬EXCEL 的功能 當然 還是要教育USER,使用上的觀念!!