Dim Val As Object = e.Form.Controls("TextBox4").Value
If val <>"" Then
e.Form.Controls("ComboBox5").ComboList = DataTables("业务").GetComboListString("流向", "[客户] ='" & Val & "'")
Else
e.Form.Controls("ComboBox5").ComboList = DataTables("业务").GetComboListString("流向")
End If
这样看看