Why we cant use Server.Transfer() to redirect on a

问题:

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.

回答1:

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.

回答2:

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:

回答3:

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.

回答4:

Take a look at Server.Transfer Vs. Response.Redirect

回答5:

Sessions is not shared among servers so that would be a big problem.