请教一个小问题？

Question

我怎么控制memo控件每行只可以输入规定的字符数呢？

Answer 1

var
  Form1: TForm1;
  Lpos,Cpos,Linelength:integer; //Lpos返回行的位置，Cpos返回字符位置，LineLength返回选中的长度implementation{$R *.dfm}procedure TForm1.Memo1KeyDown(Sender: TObject; var Key: Word;
  Shift: TShiftState);
begin
  Lpos:=SendMessage(Memo1.Handle,EM_LINEFROMCHAR,Memo1.SelStart,0);
  Cpos:=SendMessage(Memo1.Handle,EM_LINEINDEX,Lpos,0);
  LineLength:=SendMessage(Memo1.Handle,EM_LINELENGTH,Cpos,0);
  Cpos:=Memo1.SelStart-Cpos;
  if Cpos>=9 then    //如果 规定10个字符
     keybd_event( VK_RETURN, MapVirtualKey( VK_RETURN, 0 ), 0 , 0 );
end;