Delphi richedit获取选中文字

function TForm1.GetSendText(RichEdit: TExRichEdit): string;
var
MsgListInfo: TStrings;
i, m, n: integer;
x, y: LongInt;
WideStr: WideString;
begin
Result := '';
MsgListInfo := RichEdit.Lines;
Y := SendMessage(RichEdit.Handle, EM_LINEFROMCHAR, MsgList.SelStart, 0); //得到rich光标所在行与列
X := RichEdit.SelStart - SendMessage(RichEdit.Handle, EM_LINEINDEX, Y, 0);
if RichEdit.SelLength = 0 then
begin
for i := y downto 0 do
begin
m := Pos('[', MsgListInfo.Strings[i]);
n := Pos(']', MsgListInfo.Strings[i]);
if (m = 1) and (n = 21) then
begin
Result := Copy(MsgListInfo.Strings[i], m + 1, n - 2);
Break;
end;
end;
end else
begin
WideStr := MsgListInfo.Strings[y];
Result :=Copy(WideStr, x + 1, RichEdit.SelLength);
end;
end;