private void lbluserName_DoubleClick(object sender, EventArgs e)
        {
            txtReadName.Visible = true;
            txtReadName.Enabled = true;
        }

        private void txtReadName_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                lbluserName.Text = txtReadName.Text;
                txtReadName.Visible = false;
                txtReadName.Enabled = false;
            }
        }