ASP.NET 4.0

Tip : ASP.NET 4 Setting Client IDs

Rajesh Pillai — Sat, 28 Nov 2009 10:16:41 GMT

ASP.NET 4 Setting Client IDs

Another most wanted feature of asp.net 4 is the ability control client ID generation. At least I am happy with this. With prior
version of asp.net it was always difficult control the control id generation though not impossible. Why is this important? If you
can control ID generation then the markup size may dramatially reduce which may result in improved performance. The gain
may around 15% reduction in terms of markup size in case of complicated nested pages.

The new ClientIDMode property addresses this long standing issue in ASP.NET. Knowing the id attribute for rendered
elements are important if your application uses client script that references these elements.

The new CLientIDMode property lets you specify more precisely how the client ID is generated for controls. You can set the
ClientIDMode property for any control, including for the page. Following are the possible settings

AutoID
This is the same as earlier versions of asp.net.

Static
This specifies that the ClientID value will be the same as the ID without concatenating the IDs of parent naming
containers. This can be useful in Web user controls.

Predictable
This option is primarily for use in data controls that use repeating templates. It concatenates the ID properties
of the control's naming containers, but generated ClientID values do not contain strings like "ctlxxx". This setting
works in conjuction with the ClientIDRowSuffix propertyof the control. You set the ClientIDRowSuffix property to
the name of a data field, and the vlaue of that field is used as the suffix for the generated ClientID value. It's
recommended to use the primary key of a data record as the ClientIDRowSuffix value.

Inherit
This setting is the default behaviour for controls. It specifie that a control's ID generation is the same as its parent.

ClientIDMode can be set at the page or control level or in the configuration. To set it at the page level refer the below example

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default"
ClientIDMode = "Predictbale" %>

The following example shows hwo to To set it in the configuration file
<system.web>
<pages clientIDMode ="Predictable"></pages>
</system.web>

For detailed reading refer
www.asp.net/LEARN/whitepapers/aspnet4/default.aspx

I have found this feature very handy. Hope you will like it too.

Happy Programming !!!

Tip: ASP.NET 4 Permanently Redirecting a page

Rajesh Pillai — Sat, 28 Nov 2009 09:46:42 GMT

ASP.NET 4 Permanently Redirecting a page

You may have faced this problem of moving pages in a web applications around which can leat to an
accumulation of state links in search engines. Traditionally developers have handled requests to old URL's by using
Response.Redirect method to forward request to new URL.

However as you may be aware of the Redirect method issues an HTTP 302 Found status (temporary redirect) response
, which results in an extra HTTP round trip to the server when users attempt to access the old URL's. This has a performance
implication as well because of the round trip.

ASP.NET 4 adds a new RedirectPermannent helper method which makes it easy to issue HTTP 301 Moved Permanently
responses.

RedirectPermanent("/newlocation/oldcontent.aspx")

With this addition the search engines and other user agents that recognizse permanent redirects will store the new URL
that is associated with the content, which eliminates the unnecessary round trip made by the browser for temporary redirects.

You can verify this by observing the request in the Fiddler. For me I think this feature is pretty useful in migrating application
from old website to the new one. Will definitely save a lot of headache.

Tip: ASP.NET 4.0 State Compression

Rajesh Pillai — Sat, 28 Nov 2009 09:34:04 GMT

ASP.NET 4.0 State Compression

Session state compression was always a worry in the past. With asp.net 4.0 this feature is built into the framework.
Just modify your web.config with the following changes and you are ready to go. Now there will be less data travelling
through the wire.

<sessionState
  mode="SqlServer"
  sqlConnectionString="data source=dbserver;Initial Catalog=aspnetstate"
  allowCustomSqlDatabase="true"
  compressionEnabled="true"
/>

Just add the "compressionEnabled="true" to sessionState config. The compression is done by
.NET framework System.IO.Compression.GZipStream class.