程序代码如下所示：

Imports System.Web.UI
Imports System.ComponentModel
Imports System.Web.UI.WebControls
Imports System.Text
Imports System.Web

Namespace FlashAdRotatorNamespace FlashAdRotator.Web.UI.WebControls

<DefaultProperty("Text"), ToolboxData("<{0}:FlashAdRotator runat=server></{0}:FlashAdRotator>")> _
Public Class FlashAdRotatorClass FlashAdRotator
Inherits System.Web.UI.WebControls.AdRotator
Private isFlashAD As Boolean
Private ImgUrl As String
Private NavUrl As String


'/ <summary>
'/ 将此控件呈现给指定的输出参数。
'/ </summary>
'/ <param name="output"> 要写出到的 HTML 编写器 </param>



Protected Overrides Sub Render()Sub Render(ByVal writer As System.Web.UI.HtmlTextWriter)
If Me.isFlashAD Then
Imports System.Web.UI
Imports System.ComponentModel
Imports System.Web.UI.WebControls
Imports System.Text
Imports System.Web

Namespace FlashAdRotatorNamespace FlashAdRotator.Web.UI.WebControls

<DefaultProperty("Text"), ToolboxData("<{0}:FlashAdRotator runat=server></{0}:FlashAdRotator>")> _
Public Class FlashAdRotatorClass FlashAdRotator
Inherits System.Web.UI.WebControls.AdRotator
Private isFlashAD As Boolean
Private ImgUrl As String
Private NavUrl As String


'/ <summary>
'/ 将此控件呈现给指定的输出参数。
'/ </summary>
'/ <param name="output"> 要写出到的 HTML 编写器 </param>



Protected Overrides Sub Render()Sub Render(ByVal writer As System.Web.UI.HtmlTextWriter)
If Me.isFlashAD Then
Dim StringFormat As StringBuilder = New StringBuilder("<object classid=""clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"" ")
StringFormat.Append("codebase=""http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,29,0"" width={0} height={1}>")
StringFormat.Append(" <param name=""movie"" value={2}>")
StringFormat.Append(" <param name=""quality"" value=""high"">")
StringFormat.Append(" <embed src={3} quality=""high"" ")
StringFormat.Append(" pluginspage=""http://www.macromedia.com/go/getflashplayer"" type=""application/x-shockwave-flash""></embed></object>")

Dim OutPutString As StringBuilder = New StringBuilder
' OutPutString.AppendFormat(StringFormat.ToString, Me.Width, Me.Height, Me.ResolveUrl(StringUnit.CombineURL(Me.AdvertisementFile, Me.ImgUrl)), Me.ResolveUrl(StringUnit.CombineURL(Me.AdvertisementFile, Me.ImgUrl)))
OutPutString.AppendFormat(StringFormat.ToString, Me.Width, Me.Height, Me.ImgUrl, Me.ImgUrl)

writer.Write(OutPutString.ToString)
Else
MyBase.Render(writer)
End If
End Sub

Protected Overrides Sub OnAdCreated()Sub OnAdCreated(ByVal e As AdCreatedEventArgs)
MyBase.OnAdCreated(e)
If e.ImageUrl.ToLower().IndexOf(".swf") <> -1 Then
Me.isFlashAD = True
Me.ImgUrl = e.ImageUrl
Me.NavUrl = e.NavigateUrl
Else
Me.isFlashAD = False
End If
End Sub

End Class
Public Class FlashAdRotatorDesigner
Inherits System.Web.UI.Design.WebControls.AdRotatorDesigner
End Class 'FlashAdRotatorDesignerDim StringFormat As StringBuilder = New StringBuilder("<object classid=""clsid:D27CDB6E-AE6D-    11cf-96B8-444553540000"" ")
StringFormat.Append("codebase=""http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,29,0"" width={0} height={1}>")
StringFormat.Append(" <param name=""movie"" value={2}>")
StringFormat.Append(" <param name=""quality"" value=""high"">")
StringFormat.Append(" <embed src={3} quality=""high"" ")
StringFormat.Append(" pluginspage=""http://www.macromedia.com/go/getflashplayer"" type=""application/x-shockwave-flash""></embed></object>")

Dim OutPutString As StringBuilder = New StringBuilder
' OutPutString.AppendFormat(StringFormat.ToString, Me.Width, Me.Height, Me.ResolveUrl(StringUnit.CombineURL(Me.AdvertisementFile, Me.ImgUrl)), Me.ResolveUrl(StringUnit.CombineURL(Me.AdvertisementFile, Me.ImgUrl)))
OutPutString.AppendFormat(StringFormat.ToString, Me.Width, Me.Height, Me.ImgUrl, Me.ImgUrl)

writer.Write(OutPutString.ToString)
Else
MyBase.Render(writer)
End If
End Sub

Protected Overrides Sub OnAdCreated()Sub OnAdCreated(ByVal e As AdCreatedEventArgs)
MyBase.OnAdCreated(e)
If e.ImageUrl.ToLower().IndexOf(".swf") <> -1 Then
Me.isFlashAD = True
Me.ImgUrl = e.ImageUrl
Me.NavUrl = e.NavigateUrl
Else
Me.isFlashAD = False
End If
End Sub

End Class
Public Class FlashAdRotatorDesigner
Inherits System.Web.UI.Design.WebControls.AdRotatorDesigner
End Class 'FlashAdRotatorDesigner