OpenTween.HashtagManage.UseHashText_KeyPress C# (CSharp) Method

        private void UseHashText_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar == '#')
            {
                _hashSupl.ShowDialog();
                if (!string.IsNullOrEmpty(_hashSupl.inputText))
                {
                    string fHalf = "";
                    string eHalf = "";
                    int selStart = UseHashText.SelectionStart;
                    if (selStart > 0)
                    {
                        fHalf = UseHashText.Text.Substring(0, selStart);
                    }
                    if (selStart < UseHashText.Text.Length)
                    {
                        eHalf = UseHashText.Text.Substring(selStart);
                    }
                    UseHashText.Text = fHalf + _hashSupl.inputText + eHalf;
                    UseHashText.SelectionStart = selStart + _hashSupl.inputText.Length;
                }
                e.Handled = true;
            }
        }