System.Data.dll中发生类型为'System.Data.SqlClient.SqlExc

private void metroButtonLogin_Click(object sender, EventArgs e)
{
        try
        {
            //Your insert code here
            DataSet1TableAdapters.UsersTableAdapter userAda = new DataSet1TableAdapters.UsersTableAdapter();
            DataTable dt = userAda.GetDataByUserAndPass(metroTextBoxUser.Text, metroTextBoxPass.Text);

            if (dt.Rows.Count > 0)
            {
                //valid
                MessageBox.Show("Login Ok");
                UserID = int.Parse(dt.Rows[0]["UserID"].ToString());
                loginFlag = true;
            }
            else
            {
                // not valid
                MessageBox.Show("Access Denied");
                loginFlag = false;

            }

            Close();
        }// above is your origine code
        catch (System.Data.SqlClient.SqlException sqlException)
        {
            System.Windows.Forms.MessageBox.Show(sqlException.Message);
        }
}