Server.Transfer Vs. Response.Redirect

Question

What is difference between Server.Transfer and Response.Redirect?

• What are advantages and disadvantages of each?
• When is one appropriate over the other?
• When is one not appropriate?

Answer 1

Response.Redirect is more costly since it adds an extra trip to the server to figure out where to go.

Server.Transfer is more efficient however it can be a little mis-leading to the user since the Url doesn't physically change.

In my experience, the difference in performance has not been significant enough to use the latter approach

Answer 2

"response.redirect" and "server.transfer" helps to transfer user from one page to other page while the page is executing. But the way they do this transfer / redirect is very different.

In case you are visual guy and would like see demonstration rather than theory I would suggest to see the below facebook video which explains the difference in a more demonstrative way.

https://www.facebook.com/photo.php?v=762186150488997

The main difference between them is who does the transfer. In "response.redirect" the transfer is done by the browser while in "server.transfer" it’s done by the server. Let us try to understand this statement in a more detail manner.

In "Server.Transfer" following is the sequence of how transfer happens:-

1.User sends a request to an ASP.NET page. In the below figure the request is sent to "WebForm1" and we would like to navigate to "Webform2".

2.Server starts executing "Webform1" and the life cycle of the page starts. But before the complete life cycle of the page is completed “Server.transfer” happens to "WebForm2".

3."Webform2" page object is created, full page life cycle is executed and output HTML response is then sent to the browser.

While in "Response.Redirect" following is the sequence of events for navigation:-

1.Client (browser) sends a request to a page. In the below figure the request is sent to "WebForm1" and we would like to navigate to "Webform2".

2.Life cycle of "Webform1" starts executing. But in between of the life cycle "Response.Redirect" happens.

3.Now rather than server doing a redirect , he sends a HTTP 302 command to the browser. This command tells the browser that he has to initiate a GET request to "Webform2.aspx" page.

4.Browser interprets the 302 command and sends a GET request for "Webform2.aspx".

In other words "Server.Transfer" is executed by the server while "Response.Redirect" is executed by thr browser. "Response.Redirect" needs to two requests to do a redirect of the page.

So when to use "Server.Transfer" and when to use "Response.Redirect" ?

Use "Server.Transfer" when you want to navigate pages which reside on the same server, use "Response.Redirect" when you want to navigate between pages which resides on different server and domain.

Below is a summary table of which chalks out differences and in which scenario to use.

Answer 3

In addition to ScarletGarden's comment, you also need to consider the impact of search engines and your redirect. Has this page moved permanently? Temporarily? It makes a difference.

see: Response.Redirect vs. "301 Moved Permanently":

We've all used Response.Redirect at one time or another. It's the quick and easy way to get visitors pointed in the right direction if they somehow end up in the wrong place. But did you know that Response.Redirect sends an HTTP response status code of "302 Found" when you might really want to send "301 Moved Permanently"?

The distinction seems small, but in certain cases it can actually make a big difference. For example, if you use a "301 Moved Permanently" response code, most search engines will remove the outdated link from their index and replace it with the new one. If you use "302 Found", they'll continue returning to the old page...

Answer 4

Response.Redirect() will send you to a new page, update the address bar and add it to the Browser History. On your browser you can click back.

Server.Transfer() does not change the address bar. You cannot hit back.

I use Server.Transfer() when I don't want the user to see where I am going. Sometimes on a "loading" type page.

Otherwise I'll always use Response.Redirect().

Answer 5

Response.Redirect() should be used when:

• we want to redirect the request to some plain HTML pages on our server or to some other web server
• we don't care about causing additional roundtrips to the server on each request
• we do not need to preserve Query String and Form Variables from the original request
• we want our users to be able to see the new redirected URL where he is redirected in his browser (and be able to bookmark it if its necessary)

Server.Transfer() should be used when:

• we want to transfer current page request to another .aspx page on the same server
• we want to preserve server resources and avoid the unnecessary roundtrips to the server
• we want to preserve Query String and Form Variables (optionally)
• we don't need to show the real URL where we redirected the request in the users Web Browser

Answer 6

There are many differences as specified above. Apart from above all, there is one more difference. Response.Redirect() can be used to redirect user to any page which is not part of the application but Server.Transfer() can only be used to redirect user within the application.

//This will work.
Response.Redirect("http://www.google.com");

//This will not work.
Server.Transfer("http://www.google.com");