Sample code:
DataTable table = new DataTable(); // ... // insert column to table table.Columns.Add(\"name\"); // ... // insert val
It depends on your purpose but if you look at a definition of both that may tell you;
DataRow.Item Property (DataColumn) row["name"]
row["name"]
DataRowExtensions.Field Method (DataRow, DataColumn) row.Field("name")
row.Field("name")