DataGrid Columns

Hi just asking on how to add columns in DataGrid manually? using only code..

i add it in a datatable

VB Code:

Dim cn As New SqlConnection()
      cn.ConnectionString = "user id=sa;password=password;initial catalog=northwind"
      cn.Open()
 
      Dim dt As New DataTable()
      Dim cmdtext As String = "select * from categories"
 
      Dim da As New SqlDataAdapter(cmdtext, cn)
      da.Fill(dt)
      dt.Columns.Add("Brown Monkey")   'hehe
 
      DataGrid1.DataSource = dt
 
      cn.Close()