要在TMemoBox中显示的字符串内的换行符

FullMemo := txtFistMemo.Text + #13#10 + txtDetails.Text;
FullMemo := txtFistMemo.Text + sLineBreak + txtDetails.Text;

TStringList

var
  Strings: TStrings;
begin
  Strings := TStringList.Create;
  try
    Strings.Assign(txtFirstMemo.Lines); // Assuming you use a TMemo
    Strings.AddStrings(txtDetails.Lines);
    FullMemo := Strings.Text;
  finally
    Strings.Free;
  end;
end;

Strings.Add('');

FullMemo := txtFistMemo.Text + #13#10 + txtDetails.Text

FullMemo := txtFistMemo.Text + #13 + txtDetails.Text
    + Chr(13) + 'some more text'#13.

const 
 CRLF = #13#10;
 LBRK = CRLF+ CRLF;