主题：计算年龄表达式

If e.DataCol.name = "出生年月" Then
    If e.newvalue <> Nothing Then

        Dim d As Date = New Date(e.newvalue.substring(0,4), e.newvalue.substring(5,2), 1)
        Dim y As Integer = d.year
        If format(d, "MMdd") <= Format(Date.Today, "MMdd") Then
            e.DataRow("年龄") = Date.Today.Year - y
        Else
            e.DataRow("年龄") = Date.Today.Year - y -1
        End If
    Else
        e.DataRow("年龄") = Nothing
    End If
End If