主题：符合SQLReplaceFor条件的随机抽取

Dim f1 As String = "[sys_user]='" & e.DataRow("sys_user") & "' and [日龄]>='" & e.DataRow("肉猪日龄_低") & "' and [日龄]<='" & e.DataRow("肉猪日龄_高") & "'"

Dim drs As List(Of DataRow) = DataTables("肉猪信息").sqlselect(f1)
Dim count As Integer = 0
Dim ls As New List(Of Integer)
Do While count < 20
    Dim rnd As Integer = Rand.Next(drs.Count)
    If ls.Contains(rnd) = False Then
        count += 1
        drs(rnd)("栋舍") = e.DataRow("原栋舍")
        drs(rnd).save
    End If
Loop