How to pass a table-value parameter

The following example illustrates using either a DataTable or an IEnumerable<SqlDataRecord>:

SQL Code

CREATE TABLE dbo.PageView
(
    PageViewID BIGINT NOT NULL CONSTRAINT pkPageView PRIMARY KEY CLUSTERED,
    PageViewCount BIGINT NOT NULL
);
CREATE TYPE dbo.PageViewTableType AS TABLE
(
    PageViewID BIGINT NOT NULL
);
CREATE PROCEDURE dbo.procMergePageView
    @Display dbo.PageViewTableType READONLY
AS
BEGIN
    MERGE INTO dbo.PageView AS T
    USING @Display AS S
    ON T.PageViewID = S.PageViewID
    WHEN MATCHED THEN UPDATE SET T.PageViewCount = T.PageViewCount + 1
    WHEN NOT MATCHED THEN INSERT VALUES(S.PageViewID, 1);
END

C# Code

private static void ExecuteProcedure(bool useDataTable, string connectionString, IEnumerable<long> ids) {
    using (SqlConnection connection = new SqlConnection(connectionString)) {
        connection.Open();
        using (SqlCommand command = connection.CreateCommand()) {
            command.CommandText = "dbo.procMergePageView";
            command.CommandType = CommandType.StoredProcedure;

            SqlParameter parameter;
            if (useDataTable) {
                parameter = command.Parameters.AddWithValue("@Display", CreateDataTable(ids));
            }
            else {
                parameter = command.Parameters.AddWithValue("@Display", CreateSqlDataRecords(ids));
            }
            parameter.SqlDbType = SqlDbType.Structured;
            parameter.TypeName = "dbo.PageViewTableType";

            command.ExecuteNonQuery();
        }
    }
}

private static DataTable CreateDataTable(IEnumerable<long> ids) {
    DataTable table = new DataTable();
    table.Columns.Add("ID", typeof(long));
    foreach (long id in ids) {
        table.Rows.Add(id);
    }
    return table;
}

private static IEnumerable<SqlDataRecord> CreateSqlDataRecords(IEnumerable<long> ids) {
    SqlMetaData[] metaData = new SqlMetaData[1];
    metaData[0] = new SqlMetaData("ID", SqlDbType.BigInt);
    SqlDataRecord record = new SqlDataRecord(metaData);
    foreach (long id in ids) {
        record.SetInt64(0, id);
        yield return record;
    }
}

Adding a new answer with updated links.

According to the documentation (learn.microsoft.com), you can use one of the following parameter types:

SqlClient supports populating table-valued parameters from DataTable, DbDataReader or IEnumerable \ SqlDataRecord objects. You must specify a type name for the table-valued parameter by using the TypeName property of a SqlParameter. The TypeName must match the name of a compatible type previously created on the server.

Not included in the docs but important for high-performance apps, a sample using IEnumerable<SqlDataRecord> (.NET Core 3.1, async):

  using var timeout = new CancellationTokenSource(TimeSpan.FromSeconds(30));
  using SqlConnection connection = this.GetConnection();
  await connection.OpenAsync(timeout.Token);

  using SqlCommand command = connection.CreateCommand();
  command.CommandType = CommandType.StoredProcedure;
  command.CommandText = "Mycommand";

  IEnumerable<SqlDataRecord> records = // ...

  SqlParameter parameter = command.Parameters.Add("@MyObjects", SqlDbType.Structured);
  parameter.TypeName = "MyCustomTableType";
  parameter.Value = records;

  await command.ExecuteNonQueryAsync(timeout.Token);

Example using a DataTable:

  // Create a DataTable with the modified rows.  
  DataTable addedCategories = CategoriesDataTable.GetChanges(DataRowState.Added);  

  // Configure the SqlCommand and SqlParameter.  
  SqlCommand insertCommand = new SqlCommand("usp_InsertCategories", connection);  
  insertCommand.CommandType = CommandType.StoredProcedure;  
  SqlParameter tvpParam = insertCommand.Parameters.AddWithValue("@tvpNewCategories", addedCategories);  
  tvpParam.SqlDbType = SqlDbType.Structured;  

  // Execute the command.  
  insertCommand.ExecuteNonQuery(); 

Example using DbDataReader:

 // Assumes connection is an open SqlConnection.  
 // Retrieve data from Oracle.  
 OracleCommand selectCommand = new OracleCommand(  
     "Select CategoryID, CategoryName FROM Categories;",  
     oracleConnection);  
 OracleDataReader oracleReader = selectCommand.ExecuteReader(  
     CommandBehavior.CloseConnection);  

  // Configure the SqlCommand and table-valued parameter.  
  SqlCommand insertCommand = new SqlCommand(  
      "usp_InsertCategories", connection);  
  insertCommand.CommandType = CommandType.StoredProcedure;  
  SqlParameter tvpParam =  
      insertCommand.Parameters.AddWithValue(  
      "@tvpNewCategories", oracleReader);  
  tvpParam.SqlDbType = SqlDbType.Structured;  

  // Execute the command.  
  insertCommand.ExecuteNonQuery();