I was recently building a website for work, and I thought it would be cool to have the page 'remember' where the scroll position was when a postback was performed. I had set the flag in the web.config file, and forgot about it.

Awhile later I added a web service to the project, went to debug it in a browser, and got the following message:

The MaintainScrollPositionOnPostback page directive cannot be set without an htmlform.

I resolved the issue with the following steps:

• Remove the web.config maintainScrollPositionOnPostBack flag.
• Create a base page that inherites from System.Web.UI.Page
• Set maintainScrollPositionOnPostBack programmatically in the base page.
• Force all pages to inherit from the base page by setting the pageBaseType attribute for the Pages element in the web.config.

Base page code:

Public Class BasePage : Inherits Page
Private Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
If Not Page.Request.FilePath.EndsWith("asmx") Then
MyBase.MaintainScrollPositionOnPostBack = True
End If
End Sub
End Class