What is the difference between Server.Transfer and Server.Execute?
Both Server.Transfer and Server.Execute were introduced in Classic ASP 3.0 (and still work in ASP.NET).
When Server.Execute is used, a URL is passed to it as a parameter, and the control moves to this new page. Execution of code happens on the new page. Once code execution gets over, the control returns to the initial page, just after where it was called. However, in the case of Server.Transfer, it works very much the same, the difference being the execution stops at the new page itself (means the control is'nt returned to the calling page).
In both the cases, the URL in the browser remains the first page url (does'nt refresh to the new page URL) as the browser is'nt requested to do so.
asp.net interview: How to pass values between pages?
Every interviewer will expect this from you. There are several methods to pass values from one page to another page. Described below are few methods to pass values between pages:
QueryString - The QueryString method of passing values between web pages is one of the oldest methods of passing values between pages. A variable value is properly encoded before it is placed on a querystring. This is to make sure that characters that cause problems (like symbols and spaces) are encoded correctly. See the code below to see how QueryString functionality works.
//Code in InitialPage.aspx
String sString;
sString = Server.UrlEncode("string in InitialPage.aspx");
Response.Redirect("DestinationPage.aspx?Value=" & sString);
//Code in DestinationPage.aspx reads the QueryString
String sString;
sString = Request.QueryString("Value");
Response.Write("Your name is " & sString);
The data in the DestinationPage.aspx in the URL looks like this...
http://www.dotnetuncle.com/DestinationPage.aspx?Value=dotnetUncle
Context - The context object is used to send values between pages. Its similar to the session object, the difference being that, the Context object goes out of scope when the page is sent to a browser. Example code below shows how to use Context object.
'InitialPage.aspx stores value in context before sending it
Context.Items("MyData") = "dotnetuncle";
Server.Transfer("DestinationPage.aspx");
'DestinationPage.aspx retrieves the value from InitialPage.aspx's context
String sString;
sString = Context.Items("MyDate").ToString;
Response.Write("The data is as follows: " & sString);
Session - The session object is used to persist data across a user session during the user's visit to a website. It is almost same as the Context object. When we use Response.Redirect, it causes the Context object to go away, so rather the Session object is used in such a scenario. Session object uses more of server memory than a context object. Example code below shows how to use Session object.
'InitialPage.aspx stores value in session before sending it
Session.Items("MyData") = "dotnetuncle";
Response.Redirect("DestinationPage.aspx");
'DestinationPage.aspx retrieves the value from InitialPage.aspx's session
String sString;
sString = Session.Items("MyDate").ToString;
Response.Write("The data is as follows: " & sString);
asp.net interview: How to redirect a page to another page?
A common question asked in interviews. The Response object has a famous Redirect method that is used most widely to transfer a web page visitor from one page to another page.
Syntax of Response.Redirect ...
Response.Redirect("DestinationPage.aspx")
There is another famous method called Transfer method of the Server object.
Syntax of Server.Transfer ...
Server.Transfer("DestinationPage.aspx")
What is the difference between Server.Transfer and Response.Redirect? Why would I choose one over the other?
Some of we developers may confused about these 2 method,
Server.Transfer() : client is shown as it is on the requesting page only, but the all the content is of the requested page. Data can be persist accros the pages using Context.Item collection, which is one of the best way to transfer data from one page to another keeping the page state alive.
Response.Dedirect() :client know the physical loation (page name and query string as well). Context.Items loses the persisitance when nevigate to destination page.
In earlier versions of IIS, if we wanted to send a user to a new Web page, the only option we had was Response.Redirect. While this method does accomplish our goal, it has several important drawbacks. The biggest problem is that this method causes each page to be treated as a separate transaction. Besides making it difficult to maintain your transactional integrity, Response.Redirect introduces some additional headaches. First, it prevents good encapsulation of code. Second, you lose access to all of the properties in the Request object. Sure, there are workarounds, but they’re difficult. Finally, Response.Redirect necessitates a round trip to the client, which, on high-volume sites, causes scalability problems. As you might suspect, Server.Transfer fixes all of these problems. It does this by performing the transfer on the server without requiring a roundtrip to the client.
