Create WPF TextBox that accepts only numbers

Question

I would like to create a TextBox that only accepts numeric values, in a specific range. What is the best way to implement such TextBox?

I thought about deriving TextBox and to override the validation and coercion of the TextProperty. However, I am not sure how to do this, and I understand that deriving WPF control is generally not recommended.

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Edit:
What I needed was a very basic textbox that filters out all key presses which are not digits. The easiest way to achieve it is to handle the TextBox.PreviewTextInput event:

 private void textBox_PreviewTextInput(object sender, TextCompositionEventArgs e)
    {
        int result;
        if (!validateStringAsNumber(e.Text,out result,false))
        {
            e.Handled = true;
        }
    }

(validateStringAsNumber is my function that primarily use Int.TryParse)

Some of the suggested solutions are probably better, but for the simple functionality I needed this solution is the easiest and quickest to implement while sufficient for my needs.

Answer 1

There are several Numbers Only Textbox implementations out there.

Answer 2

Most implementations I have seen so far are using the PreviewTextInput event to implement the correct mask behavior. This one inherits from TextBox and this one uses attached properties. Both use .Net's MaskedTextProvider to provide the correct mask behaviour, but if you just want a simple 'numbers only' textbox you don't need this class.

Answer 3

Whats wrong with the msdn binding validation sample? Code is here

Answer 4

The overall best why is to use the override method OnKeyPressed for the textbox like. Here is the code for the override using the static Char Method IsDigit.

if (!Char.IsDigit(e.KeyChar) && !Char.IsControl(e.KeyChar)) e.Handled = true;

That is all you really need to do.