为什么类型System.TimeSpan无法转换为String?

[iathere]

我自己在VB2005下写了如下代码:
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim dt1, dt2 As DateTime
Dim days As TimeSpan
dt1 = DateTime.Now
dt2 = DateTime.Parse("2000-1-1")
days = dt1 - dt2
ErrorDays.Text = days
End Sub
但是在运行的时候总是提示类型System.TimeSpan无法转换为String,想问下各位高手这是怎么回事情,应该如何转换格式.
小弟刚上手,请大家帮我一把,谢谢~