Gets or sets a wrapping filter object that is used to modify the HTTP entity body before transmission.
Assembly: System.Web (in System.Web.dll)
When you create a Stream object and set the property to the Stream object, all HTTP output sent by Write passes through the filter.
The following example is an ASP.NET page that sets the property to a new instance of the UpperCaseFilter class, a custom Stream class that converts all text that passes through it to uppercase. The information about the request is saved to a text file, and then the property is set. After the response filter is in place, the code calls the MapPath method to get the absolute path to a text file named TestFile.txt that serves as the source for the content of the response. The code then creates a new StreamReader object to read the text file from beginning to end, and then calls the Write method to display the content of the file on the page.
<%@ Page Language="VB" Debug="true"%> <%@ Import Namespace="System.IO" %> <%@ Import Namespace="Samples.AspNet.VB.Controls" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> Private Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) ' Filter the text to be rendered as all uppercase. Response.Filter = New UpperCaseFilterStream(Response.Filter) ' Convert a virtual path to a fully qualified physical path. Dim fullpath As String = Request.MapPath("~\\TestFile.txt") Try Dim sr As StreamReader = New StreamReader(fullpath) Do While sr.Peek() >= 0 Response.Write(Convert.ToChar(sr.Read())) Loop sr.Close() Message.Text = "Reading the file was successful." Catch ex As Exception Message.Text = "The process failed." End Try End Sub </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head> <title>HttpResponse.MapPath Example</title> </head> <body> <form id="Form1" runat="server"> <asp:Label id="Message" runat="server"/> </form> </body> </html>