HI Daniel,
I've also found some other former threads you posted discussing on this
problem. Since this is a strange behavior , I'd like to confirm some other
things:
1. Are there any other controls which can autopostback such as "TextBox" ,
"CheckBox" also suffering the problem?
2. Does this problem occur in many pages or just one particular page?
3. What about creating a new simple web project and a page to do the same
test?
Here is a test page I use to test on my side, please have a check to see
whether it works.
==================aspx page=====================
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<title>AutoPostBack</title>
<meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.1">
<meta name="CODE_LANGUAGE" content="Visual Basic .NET 7.1">
<meta name="vs_defaultClientScript" content="JavaScript">
<meta name="vs_targetSchema"
content="http://schemas.microsoft.com/intellisense/ie5">
</HEAD>
<body>
<form id="Form1" method="post" runat="server">
<table width="100%" align="center">
<tr>
<td>
<asp:TextBox id="TextBox1" runat="server"
AutoPostBack="True"></asp:TextBox>
</td>
</tr>
<tr>
<td>
<asp:DropDownList id="DropDownList1" runat="server"
AutoPostBack="True">
<asp:ListItem Value="aaa" Selected="True">aaa</asp:ListItem>
<asp:ListItem Value="bbb">bbb</asp:ListItem>
<asp:ListItem Value="ccc">ccc</asp:ListItem>
<asp:ListItem Value="ddd">ddd</asp:ListItem>
</asp:DropDownList></td>
</tr>
<tr>
<td>
<asp:ListBox id="ListBox1" runat="server" AutoPostBack="True">
<asp:ListItem Value="aaa">aaa</asp:ListItem>
<asp:ListItem Value="bbb">bbb</asp:ListItem>
<asp:ListItem Value="ccc">ccc</asp:ListItem>
<asp:ListItem Value="ddd">ddd</asp:ListItem>
</asp:ListBox></td>
</tr>
</table>
</form>
</body>
</HTML>
==============code behind=====================
Public Class AutoPostBack
Inherits System.Web.UI.Page
#Region " Web Form Designer Generated Code "
'This call is required by the Web Form Designer.
<System.Diagnostics.DebuggerStepThrough()> Private Sub
InitializeComponent()
End Sub
Protected WithEvents TextBox1 As System.Web.UI.WebControls.TextBox
Protected WithEvents DropDownList1 As
System.Web.UI.WebControls.DropDownList
Protected WithEvents ListBox1 As System.Web.UI.WebControls.ListBox
'NOTE: The following placeholder declaration is required by the Web
Form Designer.
'Do not delete or move it.
Private designerPlaceholderDeclaration As System.Object
Private Sub Page_Init(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Init
'CODEGEN: This method call is required by the Web Form Designer
'Do not modify it using the code editor.
InitializeComponent()
End Sub
#End Region
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
'Put user code to initialize the page here
End Sub
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e
As System.EventArgs) Handles TextBox1.TextChanged
Response.Write("TextBox1 is AutoPostBack!")
End Sub
Private Sub DropDownList1_SelectedIndexChanged(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
DropDownList1.SelectedIndexChanged
Response.Write("DropDownList1 is AutoPostBack!")
End Sub
Private Sub ListBox1_SelectedIndexChanged(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
ListBox1.SelectedIndexChanged
Response.Write("ListBox1 is AutoPostBack!")
End Sub
End Class
================================================== ===
Regards,
Steven Cheng
Microsoft Online Support
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