带参数的SqlHelper

namespace WpfApplication3
{
    class 简化SqlHelper
    {
        private static string ConnStr = ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;

        public static int ExecuteNonQuery(string sql, params SqlParameter[] parameter)
        { 
            using(SqlConnection conn=new SqlConnection (ConnStr))
            {
                conn.Open();
                using(SqlCommand cmd=conn.CreateCommand())
                {
                    cmd.CommandText = sql;
                    cmd.Parameters.AddRange(parameter);
                    return cmd.ExecuteNonQuery();
                }
            }
        }
        public static object ExecuteScalar(string sql, params SqlParameter[] parameter)
        { 
            using(SqlConnection conn=new SqlConnection (ConnStr))
            {
                conn.Open();
                using(SqlCommand cmd=conn.CreateCommand())
                {
                    cmd.CommandText = sql;
                    cmd.Parameters.AddRange(parameter);
                    return cmd.ExecuteScalar();
                }
            }
        }
        public static DataTable ExecuteDataTable(string sql, params SqlParameter[] parameter)
        { 
            using(SqlConnection conn=new SqlConnection (ConnStr))
            {
                conn.Open();
                using(SqlCommand cmd=conn.CreateCommand())
                {
                    cmd.CommandText = sql;
                    cmd.Parameters.AddRange(parameter);
                    SqlDataAdapter adapter = new SqlDataAdapter(cmd);
                    DataSet dataset = new DataSet();
                    adapter.Fill(dataset);
                    return dataset.Tables[0];
                }
            }
        }
    }
}

       private void button1_Click(object sender, RoutedEventArgs e)
        {
           int a=(int) 简化SqlHelper.ExecuteScalar("select count(*) from Table_1 where othersnum=@num ",new SqlParameter("@num",5));
            MessageBox.Show(a.ToString());
        }