private void txbUsername_KeyPress(object sender, KeyPressEventArgs e)
 {
     if (!char.IsLetterOrDigit(e.KeyChar) && !validatorUtils.IsSpecialCharacter(e.KeyChar) && e.KeyChar != (char)Keys.Back ||
         validatorUtils.IsLetterWithAccent(e.KeyChar) || e.KeyChar == 'ª' || e.KeyChar == 'º')
     {
         e.Handled = true;
     }
 }
 private void txbEmail_KeyPress(object sender, KeyPressEventArgs e)
 {
     if (!char.IsLetterOrDigit(e.KeyChar) && e.KeyChar != (char)Keys.Back && e.KeyChar != '_' && e.KeyChar != '.' &&
         e.KeyChar != '@' || validatorUtils.IsLetterWithAccent(e.KeyChar) || e.KeyChar == 'ª' || e.KeyChar == 'º')
     {
         e.Handled = true;
     }
 }