Actualizacion de Base de Datos y DataGrid

[mariabarros]

Hola. Tengo problemas al armar la consulta de actualización de una base de datos ya que al tomar el valor de un texto dentro del datagrid al editar los datos toma el dato anterior y no el que modifico en la caja de texto.
El código de actalización es:


Sub cmUpdate(Sender As Object, e As DataGridCommandEventArgs)

rejilla.EditItemIndex = -1
Dim CurrentTextBox As TextBox
CurrentTextBox = E.Item.FindControl("txtDesc")
Dim ColValue As String = CurrentTextBox.Text

Dim connectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0; Ole DB Services=-4; Data Source=C:\BACKUP\Mis d"& _
"ocumentos\Personales\Qubika\SitiosWeb\ProvincialP laza\Provincial.mdb"
Dim dbConnection As System.Data.IDbConnection = New System.Data.OleDb.OleDbConnection(connectionString )

Dim queryString As String = "UPDATE TAB_PROMOCIONES SET promocion_desc= '" + ColValue + "' WHERE TAB_PROMOCIONES.promocion_id = " + CStr(rejilla.DataKeys(E.Item.ItemIndex))
Dim dbCommand As System.Data.IDbCommand = New System.Data.OleDb.OleDbCommand
dbCommand.CommandText = queryString
dbCommand.Connection = dbConnection

Dim dbParam_promocion_id As System.Data.IDataParameter = New System.Data.OleDb.OleDbParameter

Dim rowsAffected As Integer = 0
dbConnection.Open
Try
rowsAffected = dbCommand.ExecuteNonQuery
Finally
dbConnection.Close
End Try

label1.text=queryString

rejilla.DataBind()

End Sub