I'm new to all this and trying to only allow numeric values to be entered into an existing TextBox in ASP.Net. I've got the code for this, but can't figure out where to put it in. If I do it like the below, it creates an additional box in the textbox (that works). How can I apply this limitation to the current textbox?
<asp:TableCell>
<asp:TextBox ID="txtS2" runat="server" Width="95%" AutoPostBack="true" OnTextChanged="WerklikChanged"></asp:TextBox>
<input type="text" onkeypress="filterDigits(event)"/>
</asp:TableCell>
Update:
I ended up using the below, which is not really what I wanted as it still only checks the field once I leave the field. I'll look into blocking the entry of letters completely at a later stage and post the answer here.
<asp:CompareValidator
ID="ProgrammaticID"
ControlToValidate="txtS2KoringA"
Type="Double"
Operator="DataTypeCheck"
ErrorMessage="Error Message"
Text=" Net nommers word toegelaat in die 'Werklik' velde"
ForeColor="Red"
BackColor="White"
SetFocusOnError="false"
Display="Dynamic"
runat="server">
</asp:CompareValidator>