{"id":90,"date":"2006-05-12T15:53:04","date_gmt":"2006-05-12T14:53:04","guid":{"rendered":"http:\/\/www.galhano.com\/blog\/?p=90"},"modified":"2008-02-07T18:38:36","modified_gmt":"2008-02-07T17:38:36","slug":"servertransfer-vs-responseredirect","status":"publish","type":"post","link":"http:\/\/galhano.com\/blog\/?p=90","title":{"rendered":"Server.Transfer Vs. Response.Redirect"},"content":{"rendered":"

If you read a lot of industry magazines and ASP.NET code samples, you may find that, although the majority use Response.Redirect<\/u> to send the user to another page, some seem to prefer the rather mysterious-sounding Server.Transfer<\/u>. So, what’s the difference?<\/font><\/p>\n

Well, Response.Redirect<\/u> simply sends a message down to the browser, telling it to move to another page. So, you may run code like: <\/font><\/p>\n

Response.Redirect(\"WebForm2.aspx\")<\/font><\/pre>\n
or<\/font><\/p>\n
Response.Redirect(\"http:\/\/www.karlmoore.com\/\")<\/font><\/pre>\n
to send the user to another page.<\/font><\/p>\n
Server.Transfer<\/u> is similar in that it sends the user to another page with a statement such as Server.Transfer(“WebForm2.aspx”)<\/u>. However, the statement has a number of distinct advantages and disadvantages.<\/font><\/p>\n
Firstly, transferring to another page using Server.Transfer<\/u> 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.<\/font><\/p>\n
But watch out: because the “transfer” process can work on only those sites running on the server, you can’t use Server.Transfer<\/u> to send the user to an external site. Only Response.Redirect<\/u> can do that.<\/font><\/p>\n
Secondly, Server.Transfer<\/u> maintains the original URL in the browser. This can really help streamline data entry techniques, although it may make for confusion when debugging.<\/font><\/p>\n
That’s not all: The Server.Transfer<\/u> method also has a second parameter\u00e2\u20ac\u201d”preserveForm”. If you set this to True<\/u>, using a statement such as Server.Transfer(“WebForm2.aspx”, True)<\/u>, the existing query string and any form variables will still be available to the page you are transferring to.<\/font><\/p>\n
For example, if your WebForm1.aspx has a TextBox control called TextBox1 and you transferred to WebForm2.aspx with the preserveForm<\/u> parameter set to True<\/u>, you’d be able to retrieve the value of the original page TextBox control by referencing Request.Form(“TextBox1”)<\/u>.<\/font><\/p>\n
This technique is great for wizard-style input forms split over multiple pages. But there’s another thing you’ll want to watch out for when using the preserveForm<\/u> parameter. ASP.NET has a bug whereby, in certain situations, an error will occur when attempting to transfer the form and query string values. You’ll find this documented at http:\/\/support.microsoft.com\/default.aspx?id=kb;en-us;Q316920<\/a>.<\/font><\/p>\n
The unofficial solution is to set the enableViewStateMac<\/u> property to True<\/u> on the page you’ll be transferring to, then set it back to False<\/u>. This records that you want a definitive False<\/u> value for this property and resolves the bug.<\/font><\/p>\n
So, in brief: Response.Redirect<\/u> simply tells the browser to visit another page. Server.Transfer<\/u> 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.<\/font><\/p>\n
\nTop Tip:<\/strong> Don’t confuse Server.Transfer<\/u> with Server.Execute<\/u>, which executes the page and returns the results. It was useful in the past, but, with ASP.NET, it’s been replaced with fresher methods of development. Ignore it.<\/font>\n<\/p><\/blockquote>\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
If you read a lot of industry magazines and ASP.NET code samples, you may find that, although the majority use Response.Redirect to send the user to another page, some seem to prefer the rather mysterious-sounding Server.Transfer. So, what’s the difference? Well, Response.Redirect simply sends a message down to the browser, telling it to move to […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"close","ping_status":"close","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-90","post","type-post","status-publish","format-standard","hentry","category-aspnet","author-admin"],"_links":{"self":[{"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/90","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=90"}],"version-history":[{"count":0,"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/90\/revisions"}],"wp:attachment":[{"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=90"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=90"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/galhano.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=90"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}