An invalid data source is being used for DataList1. A valid data source must implement either IListSource or IEnumerable.

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C#

C#4.0

when i am using where statement for selecting data it is giving error
An invalid data source is being used for DataList1. A valid data source must implement either IListSource or IEnumerable.

presentation layer

protected void btnsearch_Click(object sender, EventArgs e)
        {
            Books language = new Books()
            {
                Language = txtlanguage.Text.Trim(),
            };
            List<Books> l = modle1.GetBookbylanguage(language);
            DataList1.DataSource = language;
            DataList1.DataBind();

        }

collection

public class OnlinebookCollection<T> : List<T> where T : OnlineBookBase
    {
        public string connectionString = System.Configuration.ConfigurationManager.ConnectionStrings["OnlineBookConnectionString"].ToString();

        /// <summary>
        /// Used to Fetch Data from Database.
        /// </summary>
        /// <param name="command"></param>
        public void ExecuteQuery(SqlCommand command)
        {
            try
            {
                using (SqlConnection con = new SqlConnection(connectionString))
                {
                    using (SqlCommand cmd = command)
                    {
                        cmd.Connection = con;
                        con.Open();
                        SqlDataReader reader = cmd.ExecuteReader();
                        if (reader.HasRows)
                        {
                            Load(reader);
                        }

                        reader.Close();
                        reader.Dispose();
                    }
                }
            }
            catch (Exception exc)
            {
                throw exc;
            }
        }

        /// <summary>
        /// Used to Execute the command.
        /// </summary>
        /// <param name="command"></param>
        /// <returns></returns>
        public int ExecuteNonQuery(SqlCommand command)
        {
            try
            {
                int result = 0;
                using (SqlConnection con = new SqlConnection(connectionString))
                {
                    using (SqlCommand cmd = command)
                    {
                        cmd.Connection = con;
                        con.Open();
                        result = cmd.ExecuteNonQuery();
                    }
                }
                return result;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        public object ExecuteScalar(SqlCommand command)
        {
            try
            {
                object result = null;
                using (SqlConnection con = new SqlConnection(connectionString))
                {
                    using (SqlCommand cmd = command)
                    {
                        cmd.Connection = con;
                        con.Open();
                        result = cmd.ExecuteScalar();
                    }
                }
                return result;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

        public virtual void Load(SqlDataReader reader)
        {
        }

    }
}