TOP AJAX Interview Questions and Answers
What is Ajax?
This technique is used to make internet faster and user friendly. It is not a programming language.
What are Ajax applications?
Browser based applications and platform independent applications are used by Ajax.
How many types of triggers are present in update panel?
There are two types of triggers used in update panel:
PostBackTrigger – This works as full postback and it cannot work asynchronously
AsyncPostBackTrigger – Partial post back asynchronously
What are all the controls of Ajax?
Following are the controls of Ajax:
What is the name of the DLL that contains Ajax control tool kit?
Ajaxcontroltoolkit.dll is the DLL used for Ajax control tool kit and it can be downloaded from the internet. It can be added in the tool box or copied directly in the bin folder.
What role of #&& in querystring?
# is treated as fragment delimiter to delimit the history state and && precedes is used to check on the information in the query string.
How to control the duration of an Ajax request?
AsyncPostBackTimeout property is used to control the duration of Ajax request. Default value of this property is 90 seconds.
Example – <asp:ScriptManager runat=”server” id=”sample” AsyncPostBackTimeout=”40”/>
What are the advantages of Ajax?
Following are the advantages of Ajax:
Bandwidth utilization – It saves memory when the data is fetched from the same page.
More interactive, Speeder retrieval of data
What are the disadvantages of Ajax?
Following are the disadvantages of Ajax:
Source code written in AJAX is easily human readable. There will be some security issues in Ajax.
Debugging is difficult
Increases size of the requests
Slow and unreliable network connection.
Problem with browser back button when using AJAX enabled pages.
What is update panel?
Update panel is a server control used to update the specified portion of a web page. Script Manager needs to be used whenever update panel is used. Using update panel, user cannot handle outside controls.
Which are the two methods used for cross domain Ajax calls?
There are two methods used to transfer data between the two more more security domains:
CROS – Cross Origin Resource Sharing and it works with the HTTP web browsers
JSONP – JSON with Padding which works with the HTTP GET and on legacy browsers
What are all the technologies used by Ajax?
AJAX uses following technologies:
Document Object Model (DOM)
Extensible HTML (XHTML)
Cascading Style Sheets (CSS)
What are all the features of Ajax?
Following are the features of Ajax and they are as follows:
Live data binding
Client-side template rendering
Declarative instantiation of client components
Invoking ADO.NET data services and data contexts
What is JSON in Ajax?
What are the limitations of Ajax?
An Ajax Web Application tends to confuse end users if the network bandwidth is slow and there is no full postback running.
What are the components of the ASP.NET AJAX architecture?
There are two components of AJAX Architecture:
AJAX client architecture
AJAX server architecture
What are the extender controls?
What is AJAX Control Extender Toolkit?
AJAX Control Extender Toolkit is a free download from site.
Where AJAX cannot be used?
Users cannot use AJAX if
If Page need to show in a search engine
If user wants to create secure application
What are the pre-requisites to execute AJAX applications on a server?
AJAX is a built-in functionality of .NET Framework 4.0 and AJAX application can be executed by just installing Microsoft Visual Studio 2010. To use extenders in your applications, you are required to install AJAX Control Toolkit and copy the AjaxControlToolkit.dll file to the Bin directory of your application.