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Unit 4: Advanced Server Controls
4.1.2 Difference between Web Server Control and Html Server Control Notes
Web Server Controls are collection of controls imitative straight from the arrangement.Web.
UI.WebControls base class. They are reusable components that can execute function as the
ordinary HTML controls; the real benefit of web controls is that they are programmable i.e.
they can treated and accessed the same way as any other .NET classes. They therefore respond
to events, have methods /functions and can basically do all that other .NET classes can do.
The main issue to note is that the processing of these controls is done on the server. Consider:
<asp:Button id= “MyButton” runat= “server” Text= “This is Zimcoder’s button”/>
The key attribute is the “runat” which is set to the value “server”, this is their default value
Web Server Controls are rendered as standard html to client browsers thus abreacting the
functionality. They also make it easy to deal with complex controls such as the Calendar control
which would be hell to implement in html!
HTML server controls map directly to html tags. They are defined in System.Web.
UI.HtmlControlsnamespace.The base class is System.Web.UI.HtmlControls.HtmlControl. Html
tags are converted to Html server controls by including the runat attribute in their declaration
and setting it to server. Consider
<input type= “button” id= “mybutton” name= “mybutton” value= “click me” runat= “server”>
Although these two categories may have overlapping functionality and may be even used
synonymously they have important differences. Such as
1. HTML s controls offer one to one mapping with html tags no abstraction; Web s controls
do not necessarily map to any html tag e.g. calendar control.
2. HTML attributes are not stronly typed to html s controls. Web s controls have strongly
typed attributes making for easier access to methods and properties of the base class.
3. HTML s controls do not distinguish between browsers though are not always rendered
in a predictable way across browsers. Web s controls were designed with this in mind.
4. Web server controls can be extended as the developer sees fit to come up with custom
controls not so easily or intuitively doable with htmls controls.
4.1.3 HTML Server Controls Advantage
1. ASP .NET Server Controls can detect the target browser’s capabilities and render themselves
accordingly. No issues for compatibility issues of Browsers.
2. Processing would be done at the server side.
3. ASP .NET Server Controls have an object model different from the traditional HTML and
even provide a set of properties and methods that can change the outlook and behaviour
of the controls.
4. ASP .NET Server Controls has higher level of abstraction. An output of an ASP .NET
server control can be the result of many HTML tags that combine together to produce
that control and its events. Example Grandview or Form control.
5. The HTML Server Controls follow the HTML-centric object model. Model similar to HTML.
6. Here the controls can be made to interact with Client side scripting. Processing would be
done at client as well as server depending on our code.
4.1.4 Html Server Controls Disadvantage
1. You would need to code for the browser compatibility.
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