如果插入符号直接相邻或在备忘录中的单词中,我需要能够选择 TMemo 的整个单词。
考虑以下内容(其中 | 是插入符号)
Here is some text|
= 选择text
Here is so|me text
= 选择some
|Here is some text
= 选择Here
Here is some text |
=选择''
使用注释检查此代码以解释其工作原理。
function SelectWordUnderCaret(AMemo:TMemo):string;
var
Line : Integer;
Column : Integer;
LineText: string;
InitPos : Integer;
EndPos : Integer;
begin
//Get the caret position
Line := AMemo.Perform(EM_LINEFROMCHAR,AMemo.SelStart, 0) ;
Column := AMemo.SelStart - AMemo.Perform(EM_LINEINDEX, Line, 0) ;
//Validate the line number
if AMemo.Lines.Count-1 < Line then Exit;
//Get the text of the line
LineText := AMemo.Lines[Line];
Inc(Column);
InitPos := Column;
//search the initial position using the space symbol as separator
while (InitPos > 0) and (LineText[InitPos] <> ' ') do Dec(InitPos);
Inc(Column);
EndPos := Column;
//search the final position using the space symbol as separator
while (EndPos <= Length(LineText)) and (LineText[EndPos] <> ' ') do Inc(EndPos);
//Get the text
Result := Trim(Copy(LineText, InitPos, EndPos - InitPos));
//Finally select the text in the Memo
AMemo.SelStart := AMemo.Perform(EM_LINEINDEX, Line, 0)+InitPos;
AMemo.SelLength := Length(Result);
end;
你可以像这样使用
procedure TForm1.Button1Click(Sender: TObject);
begin
Caption := SelectWordUnderCaret(Memo1) ;
end;