public DataTable GetSelectedColumns(DataTable _dataTable)
{
string[] selectedColumns = new[] { "First_Name", "Salary" };

DataTable tableWithOnlySelectedColumns =
new DataView(_dataTable).ToTable(false, selectedColumns);

return tableWithOnlySelectedColumns;
}

Read more: http://feeds.dzone.com/~r/dzone/snippets/~3/m4684X_MZJg/13813