Limit TextBox entry

How do I prevent a user from being able to entry non-numeric text in a textbox Are there textbox classes available that only accept integer values

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Limit TextBox entry

wvbotha
Perfect. Thanks.
jbaynham

You should have a look at the MaskedTextBox class where you can define a mask to be all numeric with the Mask property.
Pradeep K R

Hi again

this is little snippet that validates during the user input
Butterfly Boy

Hi

I don't think there is a textBox to perfom what you what. The way I do it is to have a class that is going to validate all your textBoxes have a looksie at this class.
netguruf

The simplest way to limit the input type, is to validate the input befour it is even shown, here I use: OnKeyPress

Here is a one method to do it, there might be some simpler way out there:

this.MyTextBox += new KeyPressEventHandler(OnlyNumbers);

void OnlyNumbers(object sender, KeyPressEventArgs e)
{
if (Convert.ToInt32('0') <= Convert.ToInt32(e.KeyChar) && Convert.ToInt32(e.KeyChar) <= Convert.ToInt32('9'))
e.Handled = false; //Allow
else
e.Handled = true; //Not allow
}

You would ofcourse have to add: backspace and so on.

Like I said, I think there are more simpler way out there, like the above user seaid, use Masked TextBox :)

Cameron Black

hi,

you can use keypress event handler to achive that

public partial class Form1 : Form

{
public Form1()
{
InitializeComponent();
//event handlers

this.textBox1.Leave += new System.EventHandler(this.textBox1_Leave);
this.textBox1.KeyPress += new System.Windows.Forms.KeyPressEventHandler(this.textBox1_KeyPress);
}
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
//this to validate during data entry

if (!char.IsNumber(e.KeyChar) && e.KeyChar != '.')
{
MessageBox.Show("plz enter numbers only");
e.Handled = true;
}
}
private void textBox1_Leave(object sender, EventArgs e)
{
//this to validate during user right click the textbox and hit past

double value;
bool result = double.TryParse(textBox1.Text,out value);
if (!result)
{
MessageBox.Show("this is not numeric \n plz insert numeric value");
textBox1.Focus();
}
}
}

hope this helps

Limit TextBox entry

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