Re: Using Response.Filter

iwilld0it — Tue, 20 Jan 2004 03:24:08 GMT

I made a slight inefficiency within the global replace ... here is the ajusted portion of the code ...



        Public Overrides Sub Write(ByVal buffer() As Byte, ByVal offset As Integer, ByVal count As Integer)





            ' Place Response Text In A String Builder





            Dim output As New StringBuilder(mEncoding.GetString(buffer, offset, count))





            ' HERE IS THE ADJUSTMENT: Perform Global Replaces


            Call output.Replace("{HOST}", "http://www.mysite.com")





            ' Write The Newly Modified Response Stream





            mFilter.Write(mEncoding.GetBytes(output.ToString), 0, output.Length)





        End Sub





    End Class

Using Response.Filter

iwilld0it — Mon, 19 Jan 2004 18:54:00 GMT

For those of u interested in using the Response.Filter property. Here is a custom filter class I wrote ...



    Public Class ResponseFilter


        Inherits IO.Stream





        Private mFilter As IO.Stream


        Private mEncoding As System.Text.Encoding





        Sub New()


            With HttpContext.Current.Response


                mFilter = .Filter


                mEncoding = .ContentEncoding


            End With


        End Sub





        Public Overrides ReadOnly Property CanRead() As Boolean


            Get


                Return mFilter.CanRead


            End Get


        End Property





        Public Overrides ReadOnly Property CanSeek() As Boolean


            Get


                Return mFilter.CanSeek


            End Get


        End Property





        Public Overrides ReadOnly Property CanWrite() As Boolean


            Get


                Return mFilter.CanWrite


            End Get


        End Property





        Public Overrides Sub Flush()


            Call mFilter.Flush()


        End Sub





        Public Overrides ReadOnly Property Length() As Long


            Get


                Return mFilter.Length


            End Get


        End Property





        Public Overrides Property Position() As Long


            Get


                Return mFilter.Position


            End Get


            Set(ByVal Value As Long)


                mFilter.Position = Value


            End Set


        End Property





        Public Overrides Function Read(ByVal buffer() As Byte, ByVal offset As Integer, ByVal count As Integer) As Integer


            If mFilter.CanRead Then


                Return mFilter.Read(buffer, offset, count)


            Else


                Return -1


            End If


        End Function





        Public Overrides Function Seek(ByVal offset As Long, ByVal origin As System.IO.SeekOrigin) As Long


            If mFilter.CanSeek Then


                Return mFilter.Seek(offset, origin)


            Else


                Return -1


            End If


        End Function





        Public Overrides Sub SetLength(ByVal value As Long)


            Call mFilter.SetLength(value)


        End Sub





        Public Overrides Sub Write(ByVal buffer() As Byte, ByVal offset As Integer, ByVal count As Integer)


            ' Place Response Text In A String Builder


            Dim output As New StringBuilder(mEncoding.GetString(buffer, offset, count))





            ' Perform Global Replaces


            output = output.Replace("{HOST}", "http://www.mysite.com")





            ' Write The Newly Modified Response Stream


            mFilter.Write(mEncoding.GetBytes(output.ToString), 0, output.Length)


        End Sub


    End Class

You can call Response.Filter in a global handler in global.asax like so ...



    Private Sub Global_PreRequestHandlerExecute(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.PreRequestHandlerExecute





         Response.Filter = New ResponseFilter()





    End Sub

Create a test page and see of it works ...

MyTest.aspx
--------------



<html>


<body>


   My Page


</body>


</html>

The Filtered HTML will translate to ...



<html>


<body>


   <a href="http://www.mysite.com/MyFolder/default.aspx">;My Page</a >


</body>


</html>

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Re: Using Response.Filter

Using Response.Filter