class DBHelper

    {

     private static string strSql = string.Format(@"server=CHENJINGLONGPC\SQLEXPRESS;database=FamilyFinace;Integrated Security=True");

     public static SqlConnection connect= new SqlConnection(strSql);

    }

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 try

                {

                    DBHelper.connect.Open();

                    string sql = string.Format(@"select count(*) from FamilyUser where UserName='{0}' and UserPassword='{1}'", txtUserName.Text.Trim(), txtPassWord.Text);

                    SqlCommand conform = new SqlCommand(sql, DBHelper.connect);

                    int result = (int)conform.ExecuteScalar();

                    if (result > 0)

                    {

                        this.DialogResult = DialogResult.OK;

                    }

                    else

                    {

                        lblUPError.Visible = true;

                    }



                    // MessageBox.Show("success");

                }