2

在Delphi中，我在保存SelStart和SelLength备忘录中遇到困难，该备忘录在选择为负/反向时每5秒更新文本。

对于负/反向选择，我的意思是我已经在某处开始选择，并且在按住 shift 的同时按了左箭头键几次。

代码：

var
  caret: TPoint;
  sel_start, sel_length: Integer;
begin
  sel_start := Memo1.SelStart;    //          =  5
  sel_length := Memo1.SelLength;  //          = 10
  caret := Memo1.CaretPos;        // caret.x  = 15

  //'adi and bl' selected
  caret.x := sel_start;
  Memo1.Lines.Clear;
  Memo1.Lines.Add('laditadi and blah blah');
  Memo1.SelStart := sel_start;
  Memo1.SelLength := sel_length;

  Memo1.CaretPos := caret;
end;

问题是设置 SelLength 似乎实际上移动了插入符号。SelLength并在设置后设置插入符号SelLength := 0;。由于文本不断变化，我不能在前后使用TMemo.SelText/ 。TMemo.SetSelText

我找不到保存插入符号位置的方法……有任何线索吗？

4

1 回答 1

2

如果 sel_start 的值与插入符号的字符位置相同，则通过将 selstart 设置为 selstart+sellength 并将 sellength 设置为 -sellength 来反转选择。

procedure TForm1.Button1Click(Sender: TObject);
var
  caret: TPoint;
  sel_start, sel_length,CharFromPos: Integer;
begin
  Memo1.SetFocus;
  GetCaretPos(Caret);
  CharFromPos := SendMessage(Memo1.Handle, EM_CHARFROMPOS, 0 ,Caret.Y*$FFFF + Caret.X) AND $FFFF;
  sel_start := Memo1.SelStart;    //          =  5
  sel_length := Memo1.SelLength;  //          = 10

  Memo1.Lines.Clear;
  Memo1.Lines.Add('laditadi and blah blah'#13#10'laditadi and blah blah');
  if  sel_start<>CharFromPos then
      begin
       Memo1.SelStart := sel_start;
       Memo1.SelLength := sel_length;
      end
    else
      begin
       Memo1.SelStart := sel_start + sel_length;
       Memo1.SelLength := - sel_length;
      end;

end;
procedure TForm1.Timer1Timer(Sender: TObject);
var
 p:Tpoint;
 b:Boolean;
 CharFromPos:Integer;
begin
   b := GetCaretPos(p);
   CharFromPos := SendMessage(Memo1.Handle, EM_CHARFROMPOS, 0 ,p.Y*$FFFF + p.X) AND $FFFF;
   Caption := Format('SelStart %d CharFromPos %d',[Memo1.SelStart,CharFromPos])
end;
于 2013-02-01T07:10:05.277 回答