德尔福 - 获取脱字符在备忘录中的整个单词

Question

如果脱字符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（其中，|是脱字符号）

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 ''

Answer 1

用注释检查这段代码以解释工作原理。

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; 

，你可以使用这样

procedure TForm1.Button1Click(Sender: TObject); 
begin 
    Caption := SelectWordUnderCaret(Memo1) ; 
end;