过滤负数

Question

   Delphi开发的， RzSpinEdit空间怎么过滤负数，  就是不能输入负数，   注意，不是输入过后进行处理。是直接不能输入负数

Answer 1

不让输入负号就行了
if(key='-')

Answer 2

  if not (key  in ['0'..'9',#8,'.'])then
      Key:=#0;是输入数字 且不要负数吧？

Answer 3

procedure Tdenglu.Button1Click(Sender: TObject);
begin
if(length(trim(edit1.text))>0) and (length(trim(edit2.text))>0) then
    begin
          with Adoquery1 do
          begin
            close;
            sql.Clear;
            sql.add('select * from yhb where username=:un and password=:pw and type=:op');
            parambyname('un').asstring:=edit1.Text;
            parambyname('pw').asstring:=edit2.Text;
            parambyname('op').asstring:=ComboBox1.Text;
            prepare;
            open;
          end;          If Adoquery1.recordcount = 0 Then
            begin
                showmessage('请确认登录的用户名和密码是否正确!');
                edit1.SetFocus;
                edit1.SelectAll;
                edit1.Text:='';
                edit2.Text:='';
                ComboBox1.Text:='';
            End
             Else
             begin
             G_number:=Adoquery1['username'];
             g_qx:=Adoquery1['type'];
             denglu.modalresult:=mrok;
             end;
     End
     Else
         begin
                showmessage('请输入登录用户名和密码!');
                edit1.SelectAll;
         end;
end;
新人不能发帖 ，请哪个高人帮我看看这段语言有什么错误啊  一直提示错误
从这一行 parambyname('un').asstring:=edit1.Text;
开始出错