表事件DataColChanged:
If e.DataCol.Name = "第三列" Then
If e.NewValue.Length = 6 Then
Dim km As String
Dim dr As DataRow
dr = DataTables("表A").Find("第一列 = '" & e.NewValue.SubString(0,4) & "'")
If dr IsNot Nothing Then '如果找到的话
km=dr("第二列")
End If
Dim dr1 As DataRow
dr1 = DataTables("表A").Find("第一列 = '" & e.NewValue & "'")
If dr1 IsNot Nothing Then '如果找到的话
km=km & "\" & dr1("第二列")
End If
e.DataRow("第四列")=km
End If
End If