No duplicate of “Server.Transfer from ASP to ASP.Net” ;-)
On an IIS web server (running Classic ASP), I have a local URL that a user is remotely redirected to. Presumably, this call is made with data in the query string or transmitted through POST data. When this request is made, I need to remove this data (especially the query string) server-side, so none will be visible to the client.
For example, the user is led to http://example.com/dir/?data=payload. This is what requested, and this is what the user’s browser will display. Now I need the request resource to strip QueryString and Form data, so that the user ends up in e.g. http://example.com/dir/.
On MSDN, they have HttpServerUtility.Transfer, which adds a boolean to the classic Server.Transfer method allowing to preserve or clear data. However, when I try this in an aspx file transfering to an asp file, I get a 0x80004005 HTTP exception (“No http handler was found for request type 'GET'”).
Is it possible at all to “redirect” from an ASP.NET file to a Classic one?
Is there another, better way to remove request data server-side?
My options would be:
Use a redirect on the page without querystrings: Response.Redirect() This will clear post data as well.
Do a HTTP Request to scrape the HTML of the other page, and view it in your current page.
I would probably do option #1
When should use server.Transfer() and Response.Redirect() in Asp.net ?
Read blog posts - Response.Redirect vs Server.Transfer by haacked and Server.Transfer vs. Response.Redirect by Jon Galloway.
Response.Redirect simply tells the browser to visit another page.
Server.Transfer helps reduce server requests, keeps the URL the same and, allows you to transfer the query string and form variables
Response.Redirect simply sends a message down to the browser, telling it to move to another page.
Server.Transfer conserves server resources. Instead of telling the browser to redirect, it simply changes the "focus" on the Web server and transfers the request.
which therefore eases the pressure on your Web server and makes your applications run faster.
can't use Server.Transfer to send the user to an external site. Only Response.Redirect can do that
Server.Transfer maintains the original URL in the browser. This can really help streamline data entry techniques, although it may make for confusion when debugging
The Server.Transfer method also has a second parameter—"preserveForm". If you set this to True, using a statement such as Server.Transfer("WebForm2.aspx", True), the existing query string and any form variables will still be available to the page you are transferring to.
So, in brief: Response.Redirect simply tells the browser to visit another page.
Server.Transfer helps reduce server requests, keeps the URL the same and, allows you to transfer the query string and form variables.
http://www.thedevheaven.com/2012/05/responseredirect-vs-servertransfer.html
I know that Server.Transfer() should be used to redirect to another ".aspx" page on the same server. But what is the reason behind why should I not use this method to redirect to aspx page on another server or html page?
Your answers are really appriciated.
Firstly, transferring to another page using Server.Transfer conserves server resources. Instead of telling the browser to redirect, it simply changes the "focus" on the Web server and transfers the request. This means you don't get quite as many HTTP requests coming through, which therefore eases the pressure on your Web server and makes your applications run faster.
But watch out: because the "transfer" process can work on only those sites running on the server, you can't use Server.Transfer to send the user to an external site. Only Response.Redirect can do that.
Secondly, Server.Transfer maintains the original URL in the browser. This can really help streamline data entry techniques, although it may make for confusion when debugging.
From : Server.Transfer vs. Response.Redirect
So, in brief: Response.Redirect simply tells the browser to visit another page. Server.Transfer helps reduce server requests, keeps the URL the same and, with a little bug-bashing, allows you to transfer the query string and form variables.
Response.Redirect is more user-friendly, as the site visitor can bookmark the page that they are redirected to.
Transferred pages appear to the client as a different url than they really are. This means that things like relative links / image paths may not work if you transfer to a page from a different directory.
Server.Transfer has an optional parameter to pass the form data to the new page.
Since the release version, this no longer works, because the Viewstate now has more security by default (The EnableViewStateMac defaults to true), so the new page isn’t able to access the form data. You can still access the values of the original page in the new page, by requesting the original handler:
The Server.Transfer() only works within one webapplication.
With Transfer, the "handling" of the request is internally (to the webserver/application) passed on to another page, so the Request object stays the same. This means that the processing needs to stay within the webapplication.
If you want to let processing continue on another webapplication, you will need a fresh Request there. This means that you will need have the browser issue an other request, so you need a Response.Redirect.
Server.Transfer can only happen for single HttpContext. Each virtual directory or app has its own HttpContext object and they know not that they co-exists! so you cannot do that.
Take a look at Server.Transfer Vs. Response.Redirect
Sessions is not shared among servers so that would be a big problem.
I read about "HTTP persistent connection" but somehow I don't seem to understand what does persistent mean in this context.
Could you'll elaborate?
It means the server doesn't close the socket once it's finished pushing out the response (so the length of the response has to be otherwise indicated, via headers or chunking), so the client can make other requests on the same socket. A web page often requests several other pieces (images, CSS, scripts, ...) on the same server as the page itself, so reusing the socket for some of those further requests to the same server can reduce overall latency compared to closing the original socket and opening new ones for all the follow-on requests.
All the discussion till now has been from the browser side of things. The browser first request the actual page, and it parses the page and finds out all other resources that it needs before it can render that page. The browser requests these resources and other dependent resources one by one. So maintaining a persistent connection is very efficient here, as the overhead of creating and destroying connections is avoided.
Now from web server side of things, a persistent connection would be one that allows it to "push" content to the web browser. Now HTTP doesn't support this. So, there are few workarounds with javascript where the page is basically refreshed after a while.
You can see this being trick being used by many web based email providers which continuously keep checking in the background for new mails. This gives a feeling that when a new mails arrives, the server "pushes" the new mail notification to the web browser. But in fact, its actually the web browser which keeps on checking the server for any new mail.
Also another point that I would like to state is that we actually don't see any page refresh that's because of another trick which allows only specific parts of the page to be refreshed by the request. (HINT: AJAX)
I think this is a switching for http or https for website browser. If you have old https:// and you are now using http for browser .htaccess file then this problem should created via yoast plugins one page crawl page. don't worry about it is not important error. For hackers this is a way to hack your website if your ssl connection is empty they should attach there page or domain to your ssl connection
e.b http://www.example.com and when you brows https://www.example.com in browser there are some other link with open your site domain.
Solution for this always use your full address for website: to protect hackers against your website use ssl and https:/ page for your website.
Then this problem have never scene in any test site or page.
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?
Response.Redirect simply sends a message (HTTP 302) down to the browser.
Server.Transfer happens without the browser knowing anything, the browser request a page, but the server returns the content of another.
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().
To be Short: Response.Redirect simply tells the browser to visit another page. Server.Transfer helps reduce server requests, keeps the URL the same and, with a little bug-bashing, allows you to transfer the query string and form variables.
Something I found and agree with (source):
Server.Transfer is similar in that it sends the user to another page
with a statement such as Server.Transfer("WebForm2.aspx"). However,
the statement has a number of distinct advantages and disadvantages.
Firstly, transferring to another page using Server.Transfer
conserves server resources. Instead of telling the browser to
redirect, it simply changes the "focus" on the Web server and
transfers the request. This means you don't get quite as many HTTP
requests coming through, which therefore eases the pressure on your
Web server and makes your applications run faster.
But watch out: because the "transfer" process can work on only those
sites running on the server; you can't use Server.Transfer to send
the user to an external site. Only Response.Redirect can do that.
Secondly, Server.Transfer maintains the original URL in the browser.
This can really help streamline data entry techniques, although it may
make for confusion when debugging.
That's not all: The Server.Transfer method also has a second
parameter—"preserveForm". If you set this to True, using a statement
such as Server.Transfer("WebForm2.aspx", True), the existing query
string and any form variables will still be available to the page you
are transferring to.
For example, if your WebForm1.aspx has a TextBox control called
TextBox1 and you transferred to WebForm2.aspx with the preserveForm
parameter set to True, you'd be able to retrieve the value of the
original page TextBox control by referencing
Request.Form("TextBox1").
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
Response.Redirect redirects page to another page after first page arrives to client. So client knows the redirection.
Server.Transfer quits current execution of the page. Client does not know the redirection. It allows you to transfer the query string and form variables.
So it depends to your needs to choose which is better.
"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.
The beauty of Server.Transfer is what you can do with it:
TextBox myTxt = (TextBox)this.Page.PreviousPage.FindControl("TextBoxID");
You can get anything from your previous page using the above method as long as you use Server.Transfer but not Response.Redirect
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...
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");
Transfer is entirely server-side. Client address bar stays constant. Some complexity about the transfer of context between requests. Flushing and restarting page handlers can be expensive so do your transfer early in the pipeline e.g. in an HttpModule during BeginRequest. Read the MSDN docs carefully, and test and understand the new values of HttpContext.Request - especially in Postback scenarios. We usually use Server.Transfer for error scenarios.
Redirect terminates the request with a 302 status and client-side roundtrip response with and internally eats an exception (minor server perf hit - depends how many you do a day) Client then navigates to new address. Browser address bar & history updates etc. Client pays the cost of an extra roundtrip - cost varies depending on latency. In our business we redirect a lot we wrote our own module to avoid the exception cost.
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
Server.Transfer doesn't change the URL in the client browser, so effectively the browser does not know you changed to another server-side handler. Response.Redirect tells the browser to move to a different page, so the url in the titlebar changes.
Server.Transfer is slightly faster since it avoids one roundtrip to the server, but the non-change of url may be either good or bad for you, depending on what you're trying to do.
Response.Redirect: tells the browser that the requested page can be found at a new location. The browser then initiates another request to the new page loading its contents in the browser. This results in two requests by the browser.
Server.Transfer: It transfers execution from the first page to the second page on the server. As far as the browser client is concerned, it made one request and the initial page is the one responding with content.
The benefit of this approach is one less round trip to the server from the client browser. Also, any posted form variables and query string parameters are available to the second page as well.
Just more details about Transfer(), it's actually is Server.Execute() + Response.End(), its source code is below (from Mono/.net 4.0):
public void Transfer (string path, bool preserveForm)
{
this.Execute (path, null, preserveForm, true);
this.context.Response.End ();
}
and for Execute(), what it is to run is the handler of the given path, see
ASP.NET does not verify that the current user is authorized to view the resource delivered by the Execute method. Although the ASP.NET authorization and authentication logic runs before the original resource handler is called, ASP.NET directly calls the handler indicated by the Execute method and does not rerun authentication and authorization logic for the new resource. If your application's security policy requires clients to have appropriate authorization to access the resource, the application should force reauthorization or provide a custom access-control mechanism.
You can force reauthorization by using the Redirect method instead of the Execute method. Redirect performs a client-side redirect in which the browser requests the new resource. Because this redirect is a new request entering the system, it is subjected to all the authentication and authorization logic of both Internet Information Services (IIS) and ASP.NET security policy.
-from MSDN
Response.Redirect involves an extra round trip and updates the address bar.
Server.Transfer does not cause the address bar to change, the server responds to the request with content from another page
e.g.
Response.Redirect:-
On the client the browser requests a page http://InitiallyRequestedPage.aspx
On the server responds to the request with 302 passing the redirect address http://AnotherPage.aspx.
On the client the browser makes a second request to the address http://AnotherPage.aspx.
On the server responds with content from http://AnotherPage.aspx
Server.Transfer:-
On the client browser requests a page http://InitiallyRequestedPage.aspx
On the server Server.Transfer to http://AnotherPage.aspx
On the server the response is made to the request for http://InitiallyRequestedPage.aspx passing back content from http://AnotherPage.aspx
Response.Redirect
Pros:-
RESTful - It changes the address bar, the address can be used to record changes of state inbetween requests.
Cons:-
Slow - There is an extra round-trip between the client and server. This can be expensive when there is substantial latency between the client and the server.
Server.Transfer
Pros:-
Quick.
Cons:-
State lost - If you're using Server.Transfer to change the state of the application in response to post backs, if the page is then reloaded that state will be lost, as the address bar will be the same as it was on the first request.
Response.Redirect
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.
It redirects the request to some plain HTML pages on our server or to some other web server.
It causes additional roundtrips to the server on each request.
It doesn’t preserve Query String and Form Variables from the original request.
It enables to see the new redirected URL where it is redirected in the browser (and be able to bookmark it if it’s necessary).
Response. Redirect simply sends a message down to the (HTTP 302) browser.
Server.Transfer
Server.Transfer() does not change the address bar, we cannot hit back.One should use Server.Transfer() when he/she doesn’t want the user to see where he is going. Sometime on a "loading" type page.
It transfers current page request to another .aspx page on the same server.
It preserves server resources and avoids the unnecessary roundtrips to the server.
It preserves Query String and Form Variables (optionally).
It doesn’t show the real URL where it redirects the request in the users Web Browser.
Server.Transfer happens without the browser knowing anything, the browser request a page, but the server returns the content of another.