Delphi 學習筆記 Listbox 著色

Delphi 學習筆記 Listbox 著色

=============================================================

ListBox  property 中的 style 選lbOwnerDrawFixed

程式中加這一段

procedure TfrmPhotoDispatch2.ListBox1DrawItem(Control: TWinControl;

  Index: Integer; Rect: TRect; State: TOwnerDrawState);

var c:Tcanvas;

    l:integer;

    sr:string;

    cr:string;

begin

    c:=Listbox1.Canvas;

    if not (odSelected in state) then

    begin

        sr:=ListBox1.Items[Index];

        l:=Pos(',',sr);

        cr:=copy(sr,l+1,length(s)-l);

        if cr='PFS' then

        begin

              c.Brush.Color:=clgreen;

              c.Font.Color:=clWhite;

              c.FillRect(Rect);

              with Rect do

                c.textout(Left,Top,copy(sr,1,l-1));

        end;

        if cr='CD_PFS' then

        begin

              c.Brush.Color:=clyellow;

              c.Font.Color:=clblue;

              c.FillRect(Rect);

              with Rect do

                c.textout(Left,Top,copy(sr,1,l-1));

        end;

        if cr='OSI_PFS' then

        begin

              c.Brush.Color:=clPurple;

              c.Font.Color:=clWhite;

              c.FillRect(Rect);

              with Rect do

                c.textout(Left,Top,copy(sr,1,l-1));

        end;

    end;

end;

Delphi 學習筆記偵測檔案夾的檔案個數

如何偵測檔案夾的檔案個數

function FileCount(filePath:string):integer;

var pathstr:string;

    sr: TSearchRec;

    FileAttrs: Integer;

begin

    pathstr:=GetCurrentDir;

    pathstr:=pathstr+'\sqlFile\*.*';

    Form1.Edit1.Text:=pathstr;

    FileAttrs := FileAttrs + faAnyFile;

    FileCount:=0;

    // FindFirst returns 0 if a file was successfully located, otherwise, it returns an //error code.

    if SysUtils.FindFirst('K:\torch\sqlFile\*.*', FileAttrs, sr) = 0 then

    begin

            with Form1.stringgrid1 do

            begin

                rowCount:=1;

                repeat

                if (sr.Attr and FileAttrs) = sr.Attr then

                begin

                   RowCount := RowCount + 1;

                   Cells[1,RowCount-1] := sr.Name;

                   Cells[2,RowCount-1] := IntToStr(sr.Size);

                   inc(FileCount);

                end;

//FindNext returns the next entry that matches the name and attributes specified in a //previous call to FindFirst. The search record must be one that was passed to FindFirst. //The return value is zero if the function was successful. Otherwise the return value is an //error code.            

    until FindNext(sr) <> 0;

            end;

    end;

end;

Delphi 學習筆記 指標

『@』是一個運算子，放在變數前面，傳回該變數再記憶體所在之位置。@也可以傳回程序或函數的記憶體位置。『^』有兩種用法，放在型態前面表示要宣告一個指標變數。放在指標變數後面，則為一個運算子，會傳回指標變數所紀錄的記憶體位置的資料值。

ex:

var x,y:Integer;

    p:^Integer;

begin

    x:=17 ;

    p:=@x;

    y:=p^;    showmessage(inttostr(y));

end;

type PInteger=^Integer; //宣告指標形態

var R:Real;

    I:Integer;

    P:Pointer;          //宣告通用型指標變數

    PI:PInteger;

begin

    P:=@R;             //任何型態變數均可指派記憶體位置給p

    PI=Pinteger(P);    //轉換通用型態指標P為整數指標

    I:=PI^;

end;

Pointer型態為通用型態指標，因為指定任何型態資料的記憶體位址，可以利用多用途的指標型態進行強制的資料型態轉換

程序型態允許開發人員以處理變數數值的方式來處理程序和函數

function Max(x,y:Integer):Integer;

begin

    if x>y then result:=x

    else result:=y;

procedure TForm1.Button3Click(Sender: TObject);

var F:function(x,y:Integer):Integer;

begin

   F:=Max; //可以將函數Max 指定給F

   showmessage(inttostr(F(3,5)));

end;end;