Delphi中让文本框中只准输入数字

在keypress中加代码：


if not (key in ['0'..'9',#8]) then
   key:=#0;

#8:退格键
#13:Enter键
#27:Esc键
#32:空格键

＃１０　换行
＃４８　０
＃１２７　ＤＥＬ

keyprees事件下
允許輸入’.’ ,’Enter’, ‘BackSpace’,’0…9 數字’
但 ‘.’只能有一個


procedure TForm1.Edit1KeyPress(Sender: TObject; var Key: Char);
var
   S : string;
begin
   S := Edit1.Text;
   if ((key = char(8))or ((key >= char(48)) and (key <= char(57))) or (key = char(13)) or (key = ‘.’)) then
   begin
     if ((key = ‘.’) and (pos(‘.’,S) > 0)) then
       key := char(0);
   end
   else
     key := char(0);
end;