Prohibit user enter key char

[DucLinh]

how to prohibit user enter the key char on key board except num key. thanks Mr Duc Linh Nguyen

[Heath Stewart]

Depends on what you want to do this. If you want to provide a numeric-only TextBox or something similar, extend the class and override IsInputKey (or a number of other methods that would do the same thing in effect):

public class NumericTextBox : TextBox
{
protected override bool IsInputKey(Keys keyData)
{
return ((keyData >= Keys.NumPad0 && keyData <= Keys.NumPad9) ||
(keyData >= Keys.D0 && keyData <= Keys.D9));
}
}

Read the class member documentation for the TextBox for more information and other methods you can override if this isn't (for some odd reason) sufficient.

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