Accept only number in a text box in asp.net with VB

[mgpsivan]

while entering data to text box it should only accept the numbers and no text should be accepted.. so how should this be done... please do reply..

[vhormaza]

while entering data to text box it should only accept the numbers and no text should be accepted.. so how should this be done... please do reply..

Hello, try this ... at the "Leave" of the control

dim tx_Value as long

if txt_Box.text = space(0) then
exit sub
endif

try
tx_value = txt_Box.text
catch
msgbox("this text box only accept numbers")
end try


Bye

[Frinavale]

Are you trying to let your user enter whatever they'd like and then checking for invalid data using code on the server ?

Or

Are you trying to prevent the user from even entering in the information in the first place?

If the second case is what you're trying to do, I believe that you will have to use JavaScript to prevent the text from ever being entered. This means you'll have to develop a client side script that simply will not allow input that doesn't match the type you're expecting. Be aware that some users can by-pass this check so it is advisable to also validate the data in your server side logic.

There is no way to really prevent users from entering certain text this using pure .NET; however, there is a nice extension developed by Microsoft for .NET that will filter your textboxes for you. If you're interested, check out the package offered by Microsoft called: ASP.NET AJAX

Cheers!

-Frinny

[pdh12783]

while entering data to text box it should only accept the numbers and no text should be accepted.. so how should this be done... please do reply..

Hi,

Try paste this code in the KeyPress event of the text box

If Asc(e.KeyChar) >= 48 And Asc(e.KeyChar) <= 57 Then
e.Handled = False
ElseIf Asc(e.KeyChar) = 46 Then
e.Handled = False
Else
e.Handled = True
End If

Thanks and Regards,

Prashant Hirapara

[radcaesar]

private void HandleKeyPress( object sender, KeyPressEventArgs e )
{
if( !char.IsDigit( e.KeyChar ) )
{
e.Handled = true;
}
}

[Frinavale]

Wow this is an old thread!

I have since written an article on this because it's such a commonly asked question.

Check out How to check if a textbox contains a number for more detail on this topic :)

The article gives you a two of ways to check this: using JavaScript and using .NET... it is advisable to use both methods to ensure that the data is valid.

Cheers!

-Frinny

[jijuanair]

Hi Prashanth,
your posting was very helpful.
i being a fresher in C# looks forward to solutions that are simple.
you are doing a great job.
keep up the good work.....
Thanking you,
Jiju A Nair

[Shashi Sadasivan]

You could make use of a regular expression validator [1-9]{1}[0-9]*

will reduce postbacks

cheers

[ktraju]

by using regular expression validator control ur problem will be solved.

[minhnhat2807]

while entering data to text box it should only accept the numbers and no text should be accepted.. so how should this be done... please do reply..

you should use javascript

var value = document.getElementById("TextBox").value
if(isNaN(value) == true)
{
alert("This is not a number!");
}

[Harsh Aggarwal]

Private Sub TextBox1_KeyPress(ByVal sender As System.Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
Dim num As Integer
num = Asc(e.KeyChar)
If num = 8 Or num = 32 Then
Exit Sub
End If

If (Not (num >=48 And num <= 57 )) Then
e.Handled = True
End If
End Sub