ASP.NET AJAX 1.0 Sample

1 Partial Class _Default

2 Inherits System.Web.UI.Page

3

4 '' Label1 is inside Update Panel.

5 '' Button1 is inside Update Panel.

6

7 '' TextBox1 is outside Update Panel.

8 '' Button2 is outside Update Panel.

9

10 Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)

11 Me.Label1.Text = "Label"

12 Me.TextBox1.Text = "TextBox"

13 '' The content of Label1 has been changed into "Label".

14 '' The content of TextBox1 hasn't been changed.

15 End Sub

16

17 Protected Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button2.Click

18 Me.Label1.Text = "Label1"

19 Me.TextBox1.Text = "TextBox1"

20 '' Both of Label1 and TextBox has changed.

21 '' Their text have been changed into "Label1" and "TextBox1".

22 End Sub

23 End Class

从这一小段Sample可以看出，确实如Microsoft ASP.NET AJAX Documents所说，UpdatePanel内的更新不会影响到UpdatePanel外的更新。同样我们也可以看到，在默认情况下UpdatePanel内发出的更新如果请求UpdtePanel外的更新，也将被屏蔽掉，当然我们可以通过设置一些参数来获得我们希望得到的结果。

通过这个Sample我们大致可以看出新的ASP.NET AJAX启动了人为划分“控件作用域”的一个机制，如此一来通过人为划分来避免一些信息丢失或无用更新的发生，用人工规划代替原来的作用域以外全部否定的“智能规划”。