DataColChanged事件,代码
Select Case e.DataCol.Name
Case "客户","客户性质","商品名称", "重量"
Dim filter As String = "客户 = '" & e.DataRow("客户") & "' and 客户性质 = '" & e.DataRow("客户性质") & "' and 商品名称 = '" & e.DataRow("商品名称") & "'"
Dim fdr As DataRow = DataTables("价格表").Find(filter & " and 最低重量 >= " & e.DataRow("重量"), "最低重量")
If fdr IsNot Nothing Then
e.DataRow("金额") = fdr("单价") * e.DataRow("重量")
End If
End Select