Visual Basic 2010 DataGridView筛选器无法正常工作

Question

两个代码段都不起作用。 我的专栏名称为rowspan

中的Shipment End

DataGridView1

和

Dim az As Date = DateTimePicker3.Value
Dim bz As Date = DateTimePicker4.Value
Me.Sheet1BindingSource.Filter = "([Shipment End]<= '" & DateTimePicker3.Value & "' and [Shipment End]>= '" & DateTimePicker4.Value & ")"