using System;

using System.Data;

public class Program

{

    public static void Main()

    {

        DataTable table = new DataTable();

        table.Columns.Add("foo", typeof(string));

        table.Columns["foo"].ColumnName = "FOO";

        table.Columns["FOO"].ColumnName = "bar";

        table.Columns["bar"].ColumnName = "foo";

    }

}