原文請見Leon.Zhou的：http: //pfzhou.cnblogs.com/archive/2006/03/31/363342.html
下載了範例程式碼，並轉換成VB了，AJAX功能測試成功。但遇到些小問題：
Demo1很正常。
Demo2按Leon原來的寫法testAJAX.aspx.vb中Line 22不成功。所以我直接在IDE環境中，修改button3的OnClientClick屬性，請參考testAJAX.asp的Line 52。測試成功。
Demo3按原來的加入客戶端屬性無法成功，在testAJAX.aspx.vb中第20行並未運作。不知道是什麼原因。 因此我只有加上一個button3來引發客戶端事件。
這是個很好的例子，值得學習，詳細原理說明請見作者的原文。測試時，請在您專案的web.config中新增<add name="NorthWind" connectionString="...對應的資料庫連接串...">
testAJAX.aspx
1<%@ Page Language="VB" AutoEventWireup="false" CodeFile="testAJAX.aspx.vb" Inherits="testAJAX" %>
2
3<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" " http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd ">
4
5<html xmlns=" http://www.w3.org/1999/xhtml " >
6<head id="Head1" runat="server">
7 <title>ASP.NET 2.0 頁面提交無刷新示範</title>
8 <script type="text/javascript" language ="javascript">
9 Function CallServer1()function CallServer1(inputcontrol, context)
10 {
11 context.innerHTML = "<IMG SRC='images/pie.gif' />Loading";
12 arg = 'ServerMethod1|' + inputcontrol.value;
13 <%= ClientScript.GetCallbackEventReference(Me, "arg", "ReceiveServerData1", "context")%>;
14 }
15
16 Function ReceiveServerData1()function ReceiveServerData1(result, context)
17 {
18 context.innerHTML = context.id + "：" + result;
19 }
20
21 Function CallServer2()function CallServer2(obj)
22 {
23 context = gridspan;
24 context.innerHTML = "<IMG SRC='images/pie.gif' />資料載入中";
25 arg = "ServerMethod2|" + obj.value;
26 <%= ClientScript.GetCallbackEventReference(Me, "arg", "ReceiveServerData2", "context")%>;
27 }
28
29 Function ReceiveServerData2()function ReceiveServerData2(result, context)
30 {
31 context.innerHTML = result;
32 }
33
34 </script>
35</head>
36<body>
37 <form id="form1" runat="server">
38 <div>
39 <h1>Demo1:html按鈕提交資料</h1><br />
40 <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
41 <input id="Button1" type="button" value="提交至Label1" onclick="CallServer1(TextBox1, Label1)"/>
42 <input id="Button2" type="button" value="提交至Label2" onclick="CallServer1(TextBox1, Label2)"/>
43 <br />
44 <asp:Label ID="Label1" runat="server" Text="Label1:"></asp:Label>
45 <br />
46 <asp:Label ID="Label2" runat="server" Text="Label2:"></asp:Label>
47 </div>
48 <hr />
49 <div>
50 <h1>Demo2:伺服器按鈕提交資料</h1><br />
51 <asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>
52 <asp:Button ID="Button3" runat="server" Text="Button" OnClientClick="CallServer1(TextBox2, Label3);return false;" /><br />
53 <asp:Label ID="Label3" runat="server" Text="Label3:"></asp:Label></div>
54 <hr />
55 <div>
56 <h1>Demo3:下拉列錶框和gridview綁定資料</h1><br />
57 <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ connectionStrings:NorthWind %>"
58 SelectCommand="select distinct(country) from customers"></asp:SqlDataSource>
59 <asp:SqlDataSource ID="SqlDataSource2" runat="server" ConnectionString="<%$ connectionStrings:NorthWind %>"
60 SelectCommand="select customerid, companyname, country from customers where country=@Country ">
61 <SelectParameters>
62 <asp:ControlParameter Name="Country" ControlID="DropDownList1" PropertyName="SelectedValue" />
63 </SelectParameters>
64 </asp:SqlDataSource>
65 <div>
66 <asp:DropDownList ID="DropDownList1" runat="server" Width="239px"
67 DataSourceID="SqlDataSource1" DataTextField="Country" DataValueField="Country">
68 </asp:DropDownList>
69 <input id="Button4" type="button" value="刷新" onclick="CallServer2(DropDownList1)"/>
70 </div>
71 <br />
72 <span id="gridspan">
73 <asp:GridView ID="GridView1" runat="server" DataSourceID="SqlDataSource2" CellPadding="4" ForeColor="#333333" GridLines="None">
74 <FooterStyle BackColor="#990000" Font-Bold="True" ForeColor="White" />
75 <RowStyle BackColor="#FFFBD6" ForeColor="#333333" />
76 <SelectedRowStyle BackColor="#FFCC66" Font-Bold="True" ForeColor="Navy" />
77 <PagerStyle BackColor="#FFCC66" ForeColor="#333333" HorizontalAlign="Center" />
78 <HeaderStyle BackColor="#990000" Font-Bold="True" ForeColor="White" />
79 <AlternatingRowStyle BackColor="White" />
80 </asp:GridView>
81 </span>
82 </div>
83 </form>
84</body>
85</html>
86
testAJAX.aspx.vb
1
2Imports System
3Imports System.Data
4Imports System.Configuration
5Imports System.Web
6Imports System.Web.Security
7Imports System.Web.UI
8Imports System.Web.UI.WebControls
9Imports System.Web.UI.WebControls.WebParts
10Imports System.Web.UI.HtmlControls
11Imports System.IO
12Imports System.Globalization
13
14Partial Public Class testAJAXClass testAJAX
15 Inherits System.Web.UI.Page
16 Implements ICallbackEventHandler
17 Protected Sub Page_Load()Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
18 '註冊客戶端事件處理方法
19 '似乎這句並沒起作用，因此我別外加了一個button4來引發客戶端事件 by AndyDavis
20 DropDownList1.Attributes.Add("onchange", "CallServer2(this)")
21 'Button3的客戶端事件可以直接在IDE中OnClientClick屬性中設置，不需要在這裡新增 by AndyDavis
22 'Button3.Attributes.Add("onclick", "CallServer1(TextBox2, Label3);return false;")
23 End Sub
24
25 Private serverReturn As String
26
27 Public Function GetCallbackResult()Function GetCallbackResult() As String Implements ICallbackEventHandler.GetCallbackResult
28 '為便於查看載入效果，新增延時
29 System.Threading.Thread.Sleep(2000)
30
31 Dim parts() As String = serverReturn.Split("|"c)
32 '根據傳遞的方法名進行調用，並傳遞相應的參數，目前只支援一個參數
33 Return CStr([GetType]().GetMethod(parts(0)).Invoke(Me, New Object() {parts(1)}))
34 End Function
35
36
37 Public Sub RaiseCallbackEvent()Sub RaiseCallbackEvent(ByVal eventArgument As String) Implements ICallbackEventHandler.RaiseCallbackEvent
38 serverReturn = eventArgument
39 End Sub
40
41 '根據從客戶傳來的英文國家名或縮寫，翻譯成相應的中文國家名
42 Public Function ServerMethod1()Function ServerMethod1(ByVal arg As String) As String
43 Dim s As String = ""
44 Select Case arg.ToLower()
45 Case "cn"
46 Case "china"
47 s = "中國"
48 Exit Select
49 Case "us"
50 s = "美國"
51 Exit Select
52 Case Else
53 s = "未知國家"
54 Exit Select
55 End Select
56 Return s
57 End Function
58
59 '根據從客戶端傳來的值，對GridView的內容進行更新，並將更新後的GridView的html傳回
60 Public Function ServerMethod2()Function ServerMethod2(ByVal arg As String) As String
61 DropDownList1.SelectedValue = arg
62 GridView1.DataBind()
63
64 Return RenderControl(GridView1)
65 End Function
66
67 Private Overloads Function RenderControl()Function RenderControl(ByVal control As Control) As String
68 Dim writer1 As StringWriter = New StringWriter(CultureInfo.InvariantCulture)
69 Dim writer2 As HtmlTextWriter = New HtmlTextWriter(writer1)
70
71 control.RenderControl(writer2)
72 writer2.Flush()
73 writer2.Close()
74
75 Return writer1.ToString()
76 End Function
77End Class
78