服务器之间的区别是什么。转移和响应。重定向?

它们各自的优点和缺点是什么? 什么时候一种比另一种更合适? 什么时候不合适?


当前回答

更多关于Transfer()的细节,它实际上是Server.Execute() + Response.End(),它的源代码如下(来自Mono/.net 4.0):

public void Transfer (string path, bool preserveForm)
{
    this.Execute (path, null, preserveForm, true);
    this.context.Response.End ();
}

对于Execute(),它要运行的是给定路径的处理程序,参见

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

其他回答

简而言之:回应。重定向只是告诉浏览器访问另一个页面。服务器。Transfer有助于减少服务器请求,保持URL相同,并且通过一些错误处理,允许您传输查询字符串和表单变量。

我发现并同意以下观点:

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").

服务器。传输不会改变客户端浏览器中的URL,因此实际上浏览器并不知道您更改了另一个服务器端处理程序。响应。重定向告诉浏览器移动到另一个页面,因此标题栏中的url会发生变化。

服务器。传输稍微快一点,因为它避免了到服务器的一次往返,但不更改url可能对您有好处,也可能有坏处,这取决于您想要做什么。

响应。重定向只是向浏览器发送一条消息(HTTP 302)。

服务器。传输在浏览器一无所知的情况下发生,浏览器请求一个页面,但服务器返回另一个页面的内容。

响应。重定向涉及一个额外的往返和更新地址栏。

服务器。传输不会导致地址栏更改,服务器会用来自另一个页面的内容响应请求

e.g.

响应。重定向:

在客户机上,浏览器请求一个页面http://InitiallyRequestedPage.aspx 在服务器上响应请求,302传递重定向地址http://AnotherPage.aspx。 在客户机上,浏览器向地址http://AnotherPage.aspx发出第二个请求。 在服务器上响应来自http://AnotherPage.aspx的内容

服务器。转让:

在客户机上,浏览器请求一个页面http://InitiallyRequestedPage.aspx 在服务器上。转至http://AnotherPage.aspx 在服务器上,对http://InitiallyRequestedPage.aspx的请求做出响应,从http://AnotherPage.aspx返回内容

响应。重定向

优点:- RESTful -它改变地址栏,地址可以用来记录请求之间的状态变化。

缺点:- 慢——在客户端和服务器之间有一个额外的往返。当客户端和服务器之间存在大量延迟时,这样做的代价可能会很高。

服务器。转移

优点:- 快。

缺点:- 状态丢失-如果您正在使用服务器。转移来改变应用程序的状态以响应回贴,如果页面随后被重新加载,该状态将丢失,因为地址栏将与第一次请求时相同。

如上所述,有许多不同之处。除此之外,还有一个不同。Response.Redirect()可用于将用户重定向到不属于应用程序的任何页面,但Server.Transfer()只能用于在应用程序内重定向用户。

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

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