delete multiple row from gridview as well database also in vb

on button click event write

Here DGListData is your grid viwe name.
the following code for delete multiple record.

  If DGListData.SelectedRows.Count >= 1 Then

            Dim x As Windows.Forms.DialogResult = MsgBox("Are You Sure To DELETE Selected Class Detail ?", MsgBoxStyle.YesNo, "")

            If x = Windows.Forms.DialogResult.Yes Then

                For Each Row In DGListData.SelectedRows

                  'here flagId is your primary key field or may which you use for delete in where condition

Dim flagId As Integer = DGListData.Item(0, Row.index).Value

                Next

            End If

          Else

            MsgBox("Please Select One or More Record", MsgBoxStyle.Information, BasicConfig.MsgInformationTitle) 

  End If