ErrorProvider example and solution to remove error icon

Refer to http://stackoverflow.com/questions/7936438/errorprovider-using-class

public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }



        private readonly ErrorProvider errorProvider1 = new ErrorProvider();



        private void textBox1_TextChanged(object sender, EventArgs e)

        {

            string text = textBox1.Text;

            bool hasDigit = false;

            foreach (char letter in text)

            {

                if (char.IsDigit(letter))

                {

                    hasDigit = true;

                    break;

                }

            }



            // Call SetError or Clear on the ErrorProvider.

            if (!hasDigit)

            {

                errorProvider1.SetError(textBox1, "Needs to contain a digit");

            }

            else

            {

                Icon i =  errorProvider1.Icon;

                errorProvider1.SetError(textBox1, "");

                i = errorProvider1.Icon;

            }

        }

    }