If Request.QueryString IsNot Nothing AndAlso _
            Request.QueryString.GetKey("id") IsNot Nothing Then
            DeleteVehicle(Request.QueryString.GetKey("id"))
 End If

System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

Line 16:         If Request.QueryString IsNot Nothing AndAlso _
Line 17:             Request.QueryString.GetKey("id") IsNot Nothing Then

Source File: G:projects_backupToaabToaaadminvehicleview.aspx.vb    Line: 16

If Request.QueryString("id") IsNot Nothing OrElse Request.QueryString("id") IsNot String.Empty Then
 DeleteVehicle(Request.QueryString("id").ToString)
End If

If String.IsNullOrEmpty(Request.QueryString("id")) = False Then
    DeleteVehicle(Request.QueryString("id"))
End If

If Request.QueryString("id") IsNot Nothing
                 AndAlso String.IsNullOrEmpty(Request.QueryString("id")) = False Then
    DeleteVehicle(Request.QueryString("id").ToString)
End If

Request.Params.AllKeys.Contains("id")