KeyPressEventArgs does not exist in the namespace 'System.Windows.Input' (are you missing an assembly reference?) Windows Phone 2012 SDK C#

Question

I am having a bug with my coding and it is really starting to get hard around

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using Business_Card.Resources;
using Windows;
using Microsoft;


namespace Business_Card
{
    public partial class MainPage : PhoneApplicationPage
    {
        // Constructor
        public MainPage()
        {
            InitializeComponent();

            // Sample code to localize the ApplicationBar
            //BuildLocalizedApplicationBar();
        }

        private void TextBox_TextChanged_1(object sender, TextChangedEventArgs e)
        {

        }

        private void TextBox_KeyPress(object sender, System.Windows.Input.KeyPressEventArgs e)    
        {

            string[] nums = { "1", "2", "3", "4", "5", "6", "7", "8", "9", "0", "-" };

            if (!nums.Contains(e.KeyChar.ToString()))

                e.Handled = true;

        }
    }
}

That is the full class

But here is the part with the error

    private void TextBox_KeyPress(object sender, System.Windows.Input.KeyPressEventArgs e)    
    {

        string[] nums = { "1", "2", "3", "4", "5", "6", "7", "8", "9", "0", "-" };

        if (!nums.Contains(e.KeyChar.ToString()))

            e.Handled = true;

    }

Specificly the line

private void TextBox_KeyPress(object sender, System.Windows.Input.KeyPressEventArgs e)    

The part where it says System.Windows.Input.KeyPressEventArgs it is telling me that the namespace or name isn't found in System.Windows.Input

I have also tried doing using System.Windows.Forms; It says Forms isn't found either and I did go the the references and it wasn't found there.

Answer 1

Try KeyDown event.

private void textBox_KeyDown(object sender, KeyEventArgs e)
{

     string[] nums = { "1", "2", "3", "4", "5", "6", "7", "8", "9", "0", "-" };
     if (!nums.Contains(e.Key.ToString()))
     e.Handled = true;
}