DataReader获取结果集架构信息

打开DataReader时，可以使用GetSchemaTable方法检索有关当前结果集的架构信息。

SqlCommand command = new SqlCommand( "SELECT CategoryID, CategoryName FROM Categories;", connection);

connection.Open();

SqlDataReader reader = command.ExecuteReader();

DataTable schemaTable = reader.GetSchemaTable();

foreach (DataRow row in schemaTable.Rows)

{     foreach (DataColumn column in schemaTable.Columns)

    {

       Console.WriteLine(String.Format("{0} = {1}",

       column.ColumnName, row[column]));

    }

}