There are always features that would be useful in fringe scenarios, but for that very reason most people don't know them. I am asking for features that are not typically taught by the text books.

What are the ones that you know?


This seems like a huge, vague question... But I will throw in Reflection, as it has allowed me to do some incredibly powerful things like pluggable DALs and such.

Geoffrey Chetwood
Reflection is of course not an hidden feature... and yes, the question is meant to be all encompassing...
I am not sure what you would define by a 'hidden feature' then. You might think of adding an example of what you consider a hidden feature.
Geoffrey Chetwood
I meant, reflection is not specific to It is something that you can use even outside of (for example, in a win forms application)
+31  A: 

HttpModules. The architecture is crazy elegant. Maybe not a hidden feature, but cool none the less.

Allain Lalonde
HttpModules is something that is advanced, but I wouldn't call it rare or less used (or call me naive). But yes, I love the architecture.
+46  A: 

HttpContext.Items as a request-level caching tool

John Sheehan
This was going to be my point as well, i use this in nested controlls to pass/receive request level information. Ii also use this in MVC to store a list of js files to append, based in partial views.
I use this when I use the routing to pass the parameters fetched from the urls to my pages. (not with MVC) great for url rewriting and is quite flexible.
Alexandre Brisebois
Hmmmm, just thought of somewhere where I could have used this instead of Session - ta!
Mike Kingscott
+15  A: 

HttpContext.IsCustomErrorEnabled is a cool feature.I've found it useful more than once. Here is a short post about it.

+41  A: 

Two things stand out in my head:

1) You can turn Trace on and off from the code:

#ifdef DEBUG 
   if (Context.Request.QueryString["DoTrace"] == "true")
                    Trace.IsEnabled = true;

2) You can build multiple .aspx pages using only one shared "code-behind" file.

Build one class .cs file :

public class Class1:System.Web.UI.Page
        public TextBox tbLogin;

        protected void Page_Load(object sender, EventArgs e)

          if (tbLogin!=null)
            tbLogin.Text = "Hello World";

and then you can have any number of .aspx pages (after you delete .designer.cs and .cs code-behind that VS has generated) :

  <%@ Page Language="C#"  AutoEventWireup="true"  Inherits="Namespace.Class1" %>
     <form id="form1" runat="server">
     <asp:TextBox  ID="tbLogin" runat="server"></asp: TextBox  >

You can have controls in the ASPX that do not appear in Class1, and vice-versa, but you need to remeber to check your controls for nulls.

I would have voted this up, but ran out of votes. I am going to try and remember to come back to vote this up. I didn't know that we could have the same Code Behind file for multiple pages. Not sure, how that would work.
Does anyone else think its a security risk to allow you to activate a trace from a url? (#1) I'm not going to downvote this question, but its important to understand the risk there.
Kevin Goff
Absolutelly, you should really put that code in a #ifdef DEBUG #endif block
Great comments, pointing out the security aspect.
Why it's a security risk to activate a trace from url? How it can be used to harm me?
+34  A: 

You can use:


To get the value of a control BEFORE viewstate is initialized (Control.Text etc will be empty at this point).

This is useful for code in Init.

+53  A: 
  • HttpContext.Current will always give you access to the current context's Request/Response/etc., even when you don't have access to the Page's properties (e.g., from a loosely-coupled helper class).

  • You can continue executing code on the same page after redirecting the user to another one by calling Response.Redirect(url, false )

  • You don't need .ASPX files if all you want is a compiled Page (or any IHttpHandler). Just set the path and HTTP methods to point to the class in the <httpHandlers> element in the web.config file.

  • A Page object can be retrieved from an .ASPX file programmatically by calling PageParser.GetCompiledPageInstance(virtualPath,aspxFileName,Context)

Mark Cidade
Wow! Upvote for you! That tip just eliminated one hell of a stupid kludge in my app.
Josh Hinman
About Response.Redirect(url, false) - That is so much what I hoped for quite a long time.. I dont know how I missed that but thanxxx
Can someone explain what you would do with this? I know it has some value, but I can't figure out why...
If you want to redirect the user to a different address but still have some back-end processing to do (e.g., a report generation request that redirects to the report's generation status page while it continues to generate the report in the background)
Mark Cidade
Can someone explain a useful situation for PageParser.GetCompiledPageInstance(..)? The docs say for it's for infrastructure use - it returns an IHttpHandler type so I don't see how it can be practically used.
John K
@jdk: I've used it in the past when overriding the default handler for *.aspx requests so I can use dynamic in-memory IHttpHandler objects but also use GetCompiledPageInstance() for physical *.aspx files.
Mark Cidade
@Mark Cidade: Thanks for the info. I'm still unclear on one point: did you cast it into a different data type to use effectively it, or did you continue to reference it through the IHttpHandler data type?
John K
@jdk: I just call the ProcessRequest() method on the IHttpHandler interface.
Mark Cidade
+80  A: 
throw new HttpException(404, "Article not found");

This will be caught by ASP.NET which will return the customErrors page. Learned about this one in a recent .NET Tip of the Day Post

John Sheehan
Some developers could argue that it's better to wrap things up manually in HttpContext.Response rather than throwing an exception which is quite expensive operation in .NET books.
lubos hasko
Isn't this bad form? You're showing the 404 error, whereas you want to display an error/exception.
Wild Thing
One case I can think of is if someone is maliciously messing with parameters and puts something invalid in, you probably want a generic 404 not a specific error.
John Sheehan
Upvoted purely because I'm now aware of the .NET Tip of the Day site.
it works only when you throw it in httpModule or httpHandler
Khaled Musaied
+15  A: 

By default, any content between tags for a custom control is added as a child control. This can be intercepted in an AddParsedSubObject() override for filtering or additional parsing (e.g., of text content in LiteralControls):

    protected override void AddParsedSubObject(object obj)
     { var literal = obj as LiteralControl;
       if (literal != null) Controls.Add(parseControl(literal.Text));
       else base.AddParsedSubObject(obj);


   <uc:MyControl runat='server'>
     ...this text is parsed as a LiteralControl...
Mark Cidade
+146  A: 

If you place a file named *app_offline.htm* in the root of a web application directory, ASP.NET 2.0+ will shut-down the application and stop normal processing any new incoming requests for that application, showing only the contents of the app_offline.htm file for all new requests.

This is the quickest and easiest way to display your "Site Temporarily Unavailable" notice while re-deploying (or rolling back) changes to a Production server.

Also, as pointed out by marxidad, make sure you have at least 512 bytes of content within the file so IE6 will render it correctly.

Troy DeMonbreun
Don't forget the workaround for IE's "friendly" messages:
Mark Cidade
Brilliant! Thanks :)
Sam Wessel
This will definately come in handy. Thanks a million
Jacob T. Nielsen
Ouch! Be careful when using this with MOSS 2007. It will only work for pages that have been accessed since the last IIS restart. So, if you add this page to your wss virtual root, then try to open a page that hadn't been accessed previously, you will get a 404.
@Marc - Got this tip from Scott Guthrie, if you are feeling generous, you would be helping a lot of SharePoint devs avoid this scenario if you commented on the Gu's article:
Troy DeMonbreun
+1 just to get this to 100 :)
@womp Bless you :-)
Troy DeMonbreun
+14  A: 

ScottGu has a bunch of tricks at

Mark Cidade
Wanted to up vote this more than once :'(
Is ScottGu a user of SO?
John K
+10  A: 

If you have ASP.NET generating an RSS feed, it will sometimes put an extra line at the top of the page. This won't validate with common RSS validators. You can work around it by putting the page directive <@Page> at the bottom of the page.

Kevin Goff
Wouldn't you do better using an .ASHX handler for generating RSS feeds?
Dan Diplo
I guess that depends on the complexity of the project. Not every one has the ability or skills to create and compile handlers. In page works reasonably well for this
Kevin Goff
And you can use something like <asp:Repeater> to generate RSS items and do other tricks (such as using the LogInView to remove some items) which is much better than writing strings from ASHX IMO
LinqToXml + ASHX is the way to go!
Carlos Muñoz
This is useful for much more than RSS feed generation. IIRC, HTML5 must have the <!doctype html> tag on the first line at the top to validate correctly.
Roy Tinker
+7  A: 

I thought it was neat when I dumped a xmlDocument() into a label and it displayed using it's xsl transforms.

a literal/placeholder would be more appropriate than a label...
+8  A: 

Setting Server Control Properties Based on Target Browser and more. That one kinda took me by surprise.

Omer van Kloeten
+1. Can you post a short code sample inline. I think it will generate more attention and upvotes. I want this one to go up.
John K
Awesome, I never knew this even existed
Carlos Muñoz
+11  A: 

Before ASP.NET v3.5 added routes you could create your own friendly URLs simply by writing an HTTPModule to and rewrite the request early in the page pipeline (like the BeginRequest event).

Urls like http://servername/page/Param1/SomeParams1/Param2/SomeParams2 would get mapped to another page like below (often using regular expressions).


DotNetNuke has a really good HttpModule that does this for their friendly urls. Is still useful for machines where you can't deploy .NET v3.5.

This requires mapping all IIS requests to ASP.NET
John Sheehan
Or just the 404 error handler.
+13  A: 

Included in ASP.NET 3.5 SP1:

  • customErrors now supports "redirectMode" attribute with a value of "ResponseRewrite". Shows error page without changing URL.
  • The form tag now recognizes the action attribute. Great for when you're using URL rewriting
John Sheehan
+226  A: 

While testing, you can have emails sent to a folder on your computer instead of an SMTP server. Put this in your web.config:

        <smtp deliveryMethod="SpecifiedPickupDirectory">
            <specifiedPickupDirectory pickupDirectoryLocation="c:\Temp\" />
John Sheehan
Really? I was about to install a fake SMTP Server, like Dumbster. I hidden gem.
Eduardo Molteni
this really is a great tip... i didn't know this...
Very cool. Thanks
Jacob T. Nielsen
G L O R I O U S !
Dave Markle
Excellent, didn't know this one
Andreas Grech
Wow! That is going to save me so much time and waiting!
Does anyone know if you can you specify a UNC share for the directory location?
Better yet, put this on your dev box machine.config, so you don't have to change the web.config on every app you create.
Max Toro
Can you set it so it only does this on local host? That way you don't have to change it every time?
There's no setting for that. You'll have to manage the config differences using other methods (Web Deployment Projects, Build tasks, etc)
John Sheehan
@Max Toro that's the real gem :) ... Note that you can already does that in Code (if you were exploring the SmtpClient properties by any means)
I thought you could do something like this through IIS. I must be mistaken, I just remember the emails going to a folder.
I think you can configure the SMTP server itself to drop everything in a folder as well, but it's server-wide so it would affect other applications.
John Sheehan
+5  A: 

Attach a class located in your App_Code folder to your Global Application Class file.

ASP.NET 2.0 - Global.asax - Code Behind file.

This works in Visual Studio 2008 as well.

+5  A: 

You can find any control by using its UniqueID property:

Label label = (Label)Page.FindControl("UserControl1$Label1");
True, but hardcoding the unique ID is bad as it is prone to change between .net runtimes.
David McEwing
UniqueID is also useful for setting a Form's Default / Accept button.
+15  A: 


This is great for determining which scripts to output (min or full versions) or anything else you might want in dev, but not live.

John Sheehan
Just use#IF DEBUG
Jan Jongboom
I agree with Jan, but sometimes it may be interesting to have an app that is aware of its execution state Debug/Release.
Alexandre Brisebois
+19  A: 


Chris Pietschmann
+27  A: 

You can use ASP.NET Comments within an .aspx page to comment out full parts of a page including server controls. And the contents that is commented out will never be sent to the client.

        <asp:Button runat="server" id="btnOne"/>
Chris Pietschmann
There are people who really don't know that there are comments?
Joe Philllips
Is this a hidden feature? :o
Arnis L.
I like it when you find half an aspx page in <!-- comments ...
Redbeard 0x0A
It is rather bare feature of ASP.NET
+6  A: 

Valid syntax that VS chokes on:

<input type="checkbox" name="roles" value='<%# Eval("Name") %>' 
  <%# ((bool) Eval("InRole")) ? "checked" : "" %> 
  <%# ViewData.Model.IsInRole("Admin") ? "" : "disabled" %> />
+15  A: 

I worked on a application which went through a security audit by a leading security company and I learned this easy trick to preventing a lesser known but important security vulnerability.

The below explanation is from:

Consider using Page.ViewStateUserKey to counter one-click attacks. If you authenticate your callers and use ViewState, set the Page.ViewStateUserKey property in the Page_Init event handler to prevent one-click attacks.

void Page_Init (object sender, EventArgs e) {
  ViewStateUserKey = Session.SessionID;

Set the property to a value you know is unique to each user, such as a session ID, user name, or user identifier.

A one-click attack occurs when an attacker creates a Web page (.htm or .aspx) that contains a hidden form field named __VIEWSTATE that is already filled with ViewState data. The ViewState can be generated from a page that the attacker had previously created, such as a shopping cart page with 100 items. The attacker lures an unsuspecting user into browsing to the page, and then the attacker causes the page to be sent to the server where the ViewState is valid. The server has no way of knowing that the ViewState originated from the attacker. ViewState validation and HMACs do not counter this attack because the ViewState is valid and the page is executed under the security context of the user.

By setting the ViewStateUserKey property, when the attacker browses to a page to create the ViewState, the property is initialized to his or her name. When the legitimate user submits the page to the server, it is initialized with the attacker's name. As a result, the ViewState HMAC check fails and an exception is generated.

Craig McKeachie
Also remember to leave base.OnInit(e); for the Page_Init() function to do its job.
I think that this trick can fail if a real user did not accept cookies, or if sessionid has timeout.
You don't need `base.OnInit(e);` if you are using `AutoEventWireup="true"` for the page.
Adam Nofsinger
+25  A: 

Usage of the ASHX file type:
If you want to just output some basic html or xml without going through the page event handlers then you can implement the HttpModule in a simple fashion

Name the page as SomeHandlerPage.ashx and just put the below code (just one line) in it

<%@ webhandler language="C#" class="MyNamespace.MyHandler" %>

Then the code file

using System;
using System.IO;
using System.Web;

namespace MyNamespace
    public class MyHandler: IHttpHandler
     public void ProcessRequest (HttpContext context)
      context.Response.ContentType = "text/xml";
      string myString = SomeLibrary.SomeClass.SomeMethod();

     public bool IsReusable
      get { return true; }
Binoj Antony
It's worth noting that you should add IRequiresSessionState or IReadOnlySessionState if you need it, otherwise it won't be there.
+44  A: 

Enabling intellisense for MasterPages in the content pages
I am sure this is a very little known hack

Most of the time you have to use the findcontrol method and cast the controls in master page from the content pages when you want to use them, the MasterType directive will enable intellisense in visual studio once you to this

just add one more directive to the page

<%@ MasterType VirtualPath="~/Masters/MyMainMasterPage.master" %>

If you do not want to use the Virtual Path and use the class name instead then

<%@ MasterType TypeName="MyMainMasterPage" %>

Get the full article here

Binoj Antony
Using the FindControl can sometimes be hectic, thanks for this great tip!
Alexandre Brisebois
Using this might result in unexpected behaviour. See
+2  A: 

ClientScript property on Page object.

+24  A: 

The Code Expression Builder (and others)

Sample markup:

Text = '<%$ Code: GetText() %>'
Text = '<%$ Code: MyStaticClass.MyStaticProperty %>'
Text = '<%$ Code: DateTime.Now.ToShortDateString() %>'
MaxLenth = '<%$ Code: 30 + 40 %>'

The real beauty of the code expression builder is that you can use databinding like expressions in non-databinding situations. You can also create other Expression Builders that perform other functions.


    <compilation debug="true">
            <add expressionPrefix="Code" type="CodeExpressionBuilder" />

The cs class that makes it all happen:

public class CodeExpressionBuilder : ExpressionBuilder
    public override CodeExpression GetCodeExpression(
        BoundPropertyEntry entry,
        object parsedData,
        ExpressionBuilderContext context)
        return new CodeSnippetExpression(entry.Expression);
Andrew Robinson
what do you mean with "and others" in the title?
Khaled Musaied
Well I guess I never got to the others.
Andrew Robinson
+1, really cool feature... That's actually quite similar to WPF's markup extensions
Thomas Levesque
+9  A: 


+33  A: 

Retail mode at the machine.config level:

    <deployment retail="true"/>

Overrides the web.config settings to enforce debug to false, turns custom errors on and disables tracing. No more forgetting to change attributes before publishing - just leave them all configured for development or test environments and update the production retail setting.

Troy Hunt
+1 - Great tip, too often overlooked.
I sometimes forget to change compilation debug to false before publishing, which negatively affects performance. No problem any more!
Roy Tinker
+7  A: 

one feature came to my mind, sometimes you will need to hide some part of your page from the crowlers. you can do it with javascript or using this simple code:

if (Request.Browser.Crawler){
Khaled Musaied
this does not always work since some crawler spoof normal traffic.
Alexandre Brisebois
+4  A: 

EnsureChildControls Method : It checks the child controls if they're initiated. If the child controls are not initiated it calls CreateChildControls method.

+8  A: 

My team uses this a lot as a hack:

WebRequest myRequest = WebRequest.Create("");
WebResponse myResponse = myRequest.GetResponse();
StreamReader sr = new StreamReader(myResponse.GetResponseStream());

// here's page's response loaded into a string for further use

String thisReturn = sr.ReadToEnd().Trim();

It loads a webpage's response as a string. You can send in post parameters too.

We use it in the place of ASCX/AJAX/WebServices when we need something cheap and fast. Basically, its a quick way to access web-available content across servers. In fact, we just dubbed it the "Redneck Web Service" yesterday.

Yep, that's pretty ghetto. ;)
Scott Hanselman
You know about the System.Net.WebClient class also, right?
Joel Coehoorn
That is too cool, Hanselman called your solution 'ghetto'!
+38  A: 

Here's the best one. Add this to your web.config for MUCH faster compilation. This is post 3.5SP1 via this QFE.

<compilation optimizeCompilations="true">

Quick summary: we are introducing a new optimizeCompilations switch in ASP.NET that can greatly improve the compilation speed in some scenarios. There are some catches, so read on for more details. This switch is currently available as a QFE for 3.5SP1, and will be part of VS 2010.

The ASP.NET compilation system takes a very conservative approach which causes it to wipe out any previous work that it has done any time a ‘top level’ file changes. ‘Top level’ files include anything in bin and App_Code, as well as global.asax. While this works fine for small apps, it becomes nearly unusable for very large apps. E.g. a customer was running into a case where it was taking 10 minutes to refresh a page after making any change to a ‘bin’ assembly.

To ease the pain, we added an ‘optimized’ compilation mode which takes a much less conservative approach to recompilation.

Via here:

Scott Hanselman
Awesome - thanks :)
Great! I wish I could up vote more than once
Alexandre Brisebois
Thank you - very important and I didn't know it.
+21  A: 


You can using ASP.NET AJAX callbacks to web methods placed in ASPX pages. You can decorate a static method with the [WebMethod()] and [ScriptMethod()] attributes. For example:

public static List<string> GetFruitBeginingWith(string letter)
 List<string> products = new List<string>() 
  "Apple", "Banana", "Blackberry", "Blueberries", "Orange", "Mango", "Melon", "Peach"

 return products.Where(p => p.StartsWith(letter)).ToList();

Now, in your ASPX page you can do this:

<form id="form1" runat="server">
  <asp:ScriptManager ID="ScriptManager1" runat="server" EnablePageMethods="true" />
  <input type="button" value="Get Fruit" onclick="GetFruit('B')" />

And call your server side method via JavaScript using:

    <script type="text/javascript">
 function GetFruit(l)
  PageMethods.GetFruitBeginingWith(l, OnGetFruitComplete);

 function OnGetFruitComplete(result)
  alert("You got fruit: " + result);
Dan Diplo
+17  A: 

One little known and rarely used feature of ASP.NET is:

Tag Mapping

It's rarely used because there's only a specific situation where you'd need it, but when you need it, it's so handy.

Some articles about this little know feature:

Tag Mapping in ASP.NET
Using Tag Mapping in ASP.NET 2.0

and from that last article:

Tag mapping allows you to swap compatible controls at compile time on every page in your web application. A useful example is if you have a stock ASP.NET control, such as a DropDownList, and you want to replace it with a customized control that is derived from DropDownList. This could be a control that has been customized to provide more optimized caching of lookup data. Instead of editing every web form and replacing the built in DropDownLists with your custom version, you can have ASP.NET in effect do it for you by modifying web.config:

   <clear />
   <add tagType="System.Web.UI.WebControls.DropDownList"
+3  A: 

Request.IsLocal Property :

It indicates whether current request is coming from Local Computer or not.

if( Request.IsLocal )
Please also check the following discussion on forums about security concerns while using Request.IsLocal property
Yes better avoid that and use - if DEBUG
+12  A: 

DefaultButton property in Panels.

It sets default button for a particular panel.

i wish I had found this ages ago!!
Alexandre Brisebois
+9  A: 

MaintainScrollPositionOnPostback attribute in Page directive. It is used to maintain scroll position of aspx page across postbacks.

A comment would be helpful to improve the answer.
+18  A: 

Check to see if the client is still connected, before starting a long-running task:

if (this.Response.IsClientConnected)
  // long-running task
+2  A: 

Similarly to the optimizeCompilations=”true” solution, here another one to speed up the time you spend waiting in between builds (very good especially if you are working with a large project): create a ram-based drive (i.e. using RamDisk) and change your default “Temporary ASP.NET Files” to this memory-based drive.

The full details on how to do this is on my blog:

Basically you first and configure a RamDisk (again, in my blog there a link to a free ramdisk) and then you change your web.config according to this:

     <compilation debug="true" tempDirectory="R:\ASP_NET_TempFiles\">

It greatly increase my development time, you just need invest in memory for you computer :)

Happy Programming!

Wagner Danda

Wagner Danda da Silva
interesting "trick"
John K
+4  A: 

Did you know it's possible to run ASP.Net outside of IIS or Visual Studio?

The whole runtime is packaged up and ready to be hosted in any process that wants to give it a try. Using ApplicationHost, HttpRuntime and HttpApplication classes, you too can grind up those .aspx pages and get shiny HTML output from them.

HostingClass host = ApplicationHost.CreateApplicationHost(typeof(HostingClass), 
                                            "/virtualpath", "physicalPath");

And your hosting class:

public class HostingClass : MarshalByRefObject
    public void ProcessPage(string url)
        using (StreamWriter sw = new StreamWriter("C:\temp.html"))
            SimpleWorkerRequest worker = new SimpleWorkerRequest(url, null, sw);
                    // Ta-dah!  C:\temp.html has some html for you.

If you use web services instead WCF services, you can still use standard .Net membership to enforce authentication and login session behaviour on a set web services similarly to a how you would secure web site with membership forms authentication & without the need for a special session and/or soap headers implementations by simply calling System.Web.Security.FormsAuthentication.SetAuthCookie(userName, false) [after calling Membership.ValidateUser(userName, password) of course] to create cookie in the response as if the user has logged in via a web form. Then you can retrieve this authentication cookie with Response.Cookies[].Value and return it as a string to the user which can be used to authenticate the user in subsequent calls by re-creating the cookie in the Application_BeginRequest by extracting the
cookie method call param from the Request.InputStream and re-creating the auth cookie before the membership authenticates the request this way the membership provider gets tricked and will know the request is authenticated and enforce all its rules.

Sample web method signature to return this cookie to the user would be: string Login(userName,password)

Sample subsequent web method call would be: string DoSomething(string authcookie,string methodParam1,int methodParam2 etc,etc) where you need to extract authcookie(which is value obtained from Login method) param from the Request.InputStreamis

This also simulates a login session and calling FormsAuthentication.SignOut in a web method like this Logout(authcookie) would make the user need to sign in again.

Ivo S
+1  A: 

Lots of people mentioned how to optimize your code when recompiling. Recently I discovered I can do most of my development (code-behind stuff) in the aspx page and skipping completely the build step. Just save the file and refresh your page. All you have to do is wrap your code in the following tag:

<script runat="server">

   Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
     Response.Write("Look Ma', I didn't even had to build!")
   End Sub


Once you are done, Just move all to the code-behind, build, test everything works and voila!


Diego C.
If you use Web site project instead of web application you can write code in code behind and will compile it for you behind the scene. You'll not need to compile the project yourself.
Branislav Abadjimarinov
Most of the time there are lots of good reasons _not_ to do this.
Joel Coehoorn
@Branislav, Yes, but for those using Web Application projects, this is a [email protected], What reasons? just to be clear, I take this approach only in development and only when working on pieces of code that might result in several trials.
Diego C.
This is bad for performance. Also, you shouldn't be using the old recordsets in
Joel Coehoorn
recordsets / reader - same thing different name
no significant difference in performance unless you're doing thousands of them.

After the website was published and deployed in the production server, If we need to do some changes on the server side button click event. We can override the existing click event by using the newkeyword in the aspx page itself.


Code Behind Method

 Protected void button_click(sender object, e System.EventArgs) 
     Response.Write("Look Ma', I Am code behind code!")  

OverRided Method:

<script runat="server">   
   Protected void new button_click(sender object, e System.EventArgs) 
     Response.Write("Look Ma', I am overrided method!")  


In this way we can easily fix the production server errors without redeployment.

Doesn't that get archaic after a while? Why is it not better to manage the build and deployment process properly? My initial reaction is this isn't a "hidden" feature but rather bad use of the well known `new` keyword.
John K
We have deployment procedures and checks to avoid anything remotely like this as well as pre-compiling any anythings...
It's not hidden feature, that's for sure! And what's the point in using code-behind if it's going to get overrided in the aspx page? Just to avoid redeploying? It defeats the whole 'code-behind' concept : Separate the code from the presentation layer.
What's the big deal about redeployment?