主题：回款额自动计算填充到订单表

做个按钮，一次性执行

Dim dt1 As DataTable = DataTables("订单表")
Dim dt2 As DataTable = DataTables("回款表")
For Each bm As String In dt2.GetValues("客户编码")
    Dim drs As List(Of DataRow) = dt1.Select("客户编码 = '" & bm & "'")
    Dim sum As Double = dt2.Compute("sum(回款额)", "客户编码 = '" & bm & "'")
    For Each cdr As DataRow In drs
        If sum > cdr("销售额") Then
            cdr("回款额") = cdr("销售额")
            sum -= cdr("销售额")
        Else
            cdr("回款额") = sum
            Exit For
        End If
    Next
Next

 引用系统菜单模板

http://www.foxtable.com/webhelp/scr/1079.htm