prevent user from enter non-numeric data in ASP.NET textboxes

Question

I'm working on an ASP.NET web project using VS2010/C#, I have some text boxes which users should enter only numbers in them, how can I prevent users from entering non-numeric, floating point numbers and negative numbers in my text boxes? of course I can check entered numbers in server side code, but I think sending data to server and performing validation will take a huge amount of time, is there a way to prevent users from entering non-numeric values? or at least not sending data to server with incorrect data?

thanks

Its too late to do it serverside (the user already tried typing something). You can easily do it with jQuery - look here http://stackoverflow.com/questions/995183/how-to-allow-only-numeric-0-9-in-html-inputbox-using-jquery — Marco Johannesen, Oct 14 '11 at 06:25

Sai Kalyan Kumar Akshinthala · Accepted Answer · 2011-10-14T07:01:11.227

2

Simply use some javascript and apply to the text box required, then it will not allow the others except numbers, see the following code part.

 <script language="JavaScript">
function onlyNumbers(evt)
{
    var e = event || evt; // for trans-browser compatibility
    var charCode = e.which || e.keyCode;

    if (charCode > 31 && (charCode < 48 || charCode > 57))
        return false;

    return true;

}
</script>

EDIT:

<asp:textbox id="txtNOD" runat="server" Width="52px" Font-Size="10px" 
 Font-Names="Verdana" Height="16px" Enabled="False" onkeypress="return onlyNumbers();"></asp:textbox>

edited Oct 14 '11 at 07:01

answered Oct 14 '11 at 06:25

Sai Kalyan Kumar Akshinthala

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thanks but how can I apply this javascript on my text box? where should I call it? – Ali_dotNet Oct 14 '11 at 06:57
1

@Ali_dotNet , see the Edited Code for that – Sai Kalyan Kumar Akshinthala Oct 14 '11 at 07:01
Hi @SaiKalyanKumarAkshinthala. Can you please tell me how can I update the code to allow period (.) as well. I have tried the following but it doesn't work. Thanks ----------------------------------------- if (charCode != 190) { ((charCode > 31 && (charCode < 48 || charCode > 57))) return false; } return true; – Rizwan606 Oct 11 '15 at 04:32

score 1 · Answer 2 · answered Oct 14 '11 at 06:25

1

You can use ASP.NET validation controls or write JavaScript to handle text/key events or even better try out jQuery or pluging to validate user input.

answered Oct 14 '11 at 06:25

KV Prajapati

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prevent user from enter non-numeric data in ASP.NET textboxes

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