（' ＃txtdistanceops'）。keydown（function（ event ）{
if （ event 。 keyCode == 46 || event .keyCode == 8 || event .keyCode == 9 ）
{

}
else
{

if （（ event .keyCode < 48 || event .keyCode > 57 ）&& ;（ event .keyCode < 96 || event .keyCode > 105 ））
{
event .preventDefault（）;

}
}
}）;

- 但这不起作用



--aspx page

 <   asp：TemplateField     HeaderText   = 批准的Km By Ops >  
<   ItemTemplate  >  
<   asp：TextBox     ID   =  txtdistanceops    MaxLength   =  6    CssClass   =  textBox_for6tds    runat   =  server >  <   / asp：TextBox  >  
<   asp：RegularExpressionValidator     ID   =  revtxtdistanceops    runat   =  server   显示  = 静态  
  
                                                                        SetFocusOnError   =  True    ValidationExpression   =  [0-9] * \。？[0-9] *     ControlToVal idate   =  txtdistanceops >  <   / asp：RegularExpressionValidator  >  
<   / ItemTemplate  > ;  
<   ItemStyle     Horizo​​ntalAlign   =  center    /  >  

- 如果按下其他任何其他内容，则应立即显示Altert消息

尝试下面的一个。

 
 
（  document ）。ready（ function （）{
 
--the textbox id is txtdistanceops


--it should allow only numberic values


like 23

24.45

46


$('#txtdistanceops').keydown(function(event) {
                     if ( event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 )
                     {

                     }
                    else
                    {

                       if ((event.keyCode < 48 || event.keyCode > 57) && (event.keyCode < 96 || event.keyCode > 105 ))
                       {
                       event.preventDefault();

                       }
                   }
                });




--but this is not working


--aspx page
<asp:TemplateField HeaderText="Approved Km By Ops">
                           <ItemTemplate>
                               <asp:TextBox ID="txtdistanceops" MaxLength="6" CssClass="textBox_for6tds" runat="server">  </asp:TextBox>
                               <asp:RegularExpressionValidator ID="revtxtdistanceops" runat="server" Display="Static"

                                   SetFocusOnError="True" ValidationExpression="[0-9]*\.?[0-9]*" ControlToValidate="txtdistanceops"></asp:RegularExpressionValidator>
                           </ItemTemplate>
                           <ItemStyle HorizontalAlign="center" />




--Altert message should be displayed immediatedly if except number anything else is pressed
('#txtdistanceops').keydown(function(event) {
                     if ( event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 )
                     {

                     }
                    else
                    {

                       if ((event.keyCode < 48 || event.keyCode > 57) && (event.keyCode < 96 || event.keyCode > 105 ))
                       {
                       event.preventDefault();

                       }
                   }
                });

--but this is not working

--aspx page

<asp:TemplateField HeaderText="Approved Km By Ops">
                           <ItemTemplate>
                               <asp:TextBox ID="txtdistanceops" MaxLength="6" CssClass="textBox_for6tds" runat="server">  </asp:TextBox>
                               <asp:RegularExpressionValidator ID="revtxtdistanceops" runat="server" Display="Static"

                                   SetFocusOnError="True" ValidationExpression="[0-9]*\.?[0-9]*" ControlToValidate="txtdistanceops"></asp:RegularExpressionValidator>
                           </ItemTemplate>
                           <ItemStyle HorizontalAlign="center" />

--Altert message should be displayed immediatedly if except number anything else is pressed

Try below one.

(document).ready(function() {