银行理财计算方式:DropDownList 绑定sqldatareader

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
OleDbDataAdapter1.Fill(DataSet11)
DataGrid1.DataBind()
Dim constr As String = "SELECT * FROM History_sp "
Dim conn As String = _
"Provider=Microsoft.Jet.OLEDB.4.0;" & _
"Data Source=C:\spdb.mdb;" & _
"User ID=Admin;" & _
"Password="
Dim mycon As OleDb.OleDbConnection = New OleDb.OleDbConnection(conn)
Dim da As DropDownList
Dim mycmd As OleDb.OleDbCommand
Dim myreader As OleDb.OleDbDataReader
mycon.Open()
mycmd = New OleDb.OleDbCommand(constr, mycon)
myreader = mycmd.ExecuteReader
da = DataGrid1.FindControl("DropDownList1")
da.DataSource = myreader.GetValue(11)
da.DataBind()
'在此处放置初始化页的用户代码
End Sub
DropDownList1是我在datagrid加的模板，我想把它绑到某一字段上可是不行
，程序哪里有问题，谢谢
我已经该为：
Private Sub DataGrid1_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DataGridItemEventArgs) Handles DataGrid1.ItemDataBound
Dim constr As String = "SELECT h2 FROM History_sp "
Dim conn As String = _
"Provider=Microsoft.Jet.OLEDB.4.0;" & _
"Data Source=C:\spdb.mdb;" & _
"User ID=Admin;" & _
"Password="
Dim mycon As OleDb.OleDbConnection = New OleDb.OleDbConnection(conn)
Dim da As DropDownList
Dim mycmd As OleDb.OleDbCommand
Dim myreader As OleDb.OleDbDataReader
mycon.Open()
mycmd = New OleDb.OleDbCommand(constr, mycon)
myreader = mycmd.ExecuteReader
da = e.Item.FindControl("DropDownList1")
da.DataSource = myreader
da.DataBind()
'在此处放置初始化页的用户代码
End Sub
但还是不行，是哪里的问题呀