主题：关于子表有多个父表的问题

你的【钢瓶号码】肯定是关联字段，可能是和别的表设置的关联，父表的关联字段是不能重复的。

 自己参考编号的生成

http://www.foxtable.com/help/topics/2403.htm

查找重复，参考 http://www.foxtable.com/help/topics/2481.htm

Datacolchanging事件，参考代码

If e.DataCol.Name = "订单号" AndAlso e.newvalue <> Nothing Then
    Dim dr As DataRow
    dr = e.DataTable.Compute("", "订单号 like '" & e.NewValue & "%'")
    If dr IsNot Nothing Then
        Dim max As String = e.DataTable.Compute("max(订单号)", "订单号 like '" & e.NewValue & "%'")
        Dim idx As Integer = val(max.SubString(e.newvalue.length)) + 1
        e.newvalue = e.newvalue & format(idx,"000")
    End If
End If

 哦，写错了

If e.DataCol.Name = "订单号" AndAlso e.newvalue <> Nothing Then
    Dim dr As DataRow
    dr = e.DataTable.find("订单号 like '" & e.NewValue & "%'")
    If dr IsNot Nothing Then
        Dim max As String = e.DataTable.Compute("max(订单号)", "订单号 like '" & e.NewValue & "%'")
        Dim idx As Integer = val(max.SubString(e.newvalue.length)) + 1
        e.newvalue = e.newvalue & format(idx,"000")
    End If
End If

如下代码

If e.DataCol.Name = "订单号" AndAlso e.newvalue <> Nothing Then
    Dim dr As DataRow
    dr = e.DataTable.find("订单号 like '" & e.NewValue & "%'")
    If dr IsNot Nothing Then
        Dim max As String = e.DataTable.Compute("max(订单号)", "订单号 like '" & e.NewValue & "%'")
        max = max.SubString(e.newvalue.length)
        If max IsNot Nothing Then
            e.newvalue = e.newvalue.PadRight(e.newvalue.length + max.Length + 1,"*")
        End If
    End If
End If