如何在Delphi中获取RichEdit的文本范围

var
  StartPos, Length: Integer;
  Text: string;
begin
  StartPos := RichEdit1.SelStart;
  Length := RichEdit1.SelLength;
  Text := RichEdit1.Text;
  // 获取选择区域的文本
  Text := Copy(Text, StartPos + 1, Length);
end;

var
  Text: string;
begin
  Text := RichEdit1.GetSelText;
end;

var
  StartPos, EndPos, Length: Integer;
  Text: string;
begin
  StartPos := 0;
  EndPos := 10;
  Length := EndPos - StartPos;
  Text := RichEdit1.Text;
  // 获取指定范围内的文本
  Text := Copy(Text, StartPos + 1, Length);
end;