→→→DataGridにフィールドの値の１部を表示する

商品コード　種別
A001          CA
B001          IC
I005           BA

Dim dCol As DataColumn

Dim dSet As DataSet = New DataSet

Dim dAdp As OleDbDataAdapter

Dim ocn As OleDbConnection = New OleDbConnection

ocn.ConnectionString = "Provider～"

dAdp = New OleDbDataAdapter ("SELECT * FROM テスト" , ocn)

dAdp.Fill( dSet, "t_テスト")

dCol = dSet.Tables("t_テスト").Columns.Add(種別)

dCol.Expression = "SUBSTRING(商品コード,1,2)"

DataGrid1.SetDataBinding( dSet , "t_テスト")