主题：筛选的问题

此主题相关图片如下：image 2.jpg

窗口中按钮的代码如下：

Tables("窗口_Table1").Filter = "张数 is null"
Dim t As Table = Tables("窗口_Table1")
For Each r As Row In t.rows
    Dim cn As Integer= Tables("出库单明细").Compute("Count(出库单号)","[出库单号] = '" & r("出库单号")  & "'")
    Dim Val As Double=cn/10
    Dim lng As Integer= Math.Ceiling(Val)
    r("张数")=lng
Next
说明：先筛选出张数是空的行，接着根据代码把张数填上。上面的代码执行后，窗口_Table1显示为空。我想要的是：填上张数之后，窗口_Table1显示的记录保持着原张数为空时一样。  

改成这样

Dim t As Table = Tables("窗口_Table1")
Dim ids As String = t.DataTable.GetComboListString("_Identify", "张数 is null")
ids = "-1," & ids.Replace("|", ",")
ids = ids.trim(",")
t.Filter = "_Identify in (" & ids & ")"
For Each r As Row In t.rows
    Dim cn As Integer= Tables("出库单明细").Compute("Count(出库单号)","[出库单号] = '" & r("出库单号")  & "'")
    Dim Val As Double=cn/10
    Dim lng As Integer= Math.Ceiling(Val)
    r("张数")=lng
Next