ASP.NET Interview Questions

Why we use postback method in c# .net?

IsPostBack is a property which returns boolean value. It checks weather the page is postedback or not."c# protected void Page_Load(object sender, EventArgs e) { ...

view state is a .net mechanism preserves the control & state on a webpage when user enter data page re-display view state for you by storing the appreciate information in hidden field on a form ;do not have to write code 2 implement viewsate;

View State is used to store the values in the current page.
Session is similar,but can hold values across the pages.

reflection is the bending of light

Reflection is the feature of C# that enables you to obtain the information about a type.

Session of an asp page expires when it reaches the time out set in the web config or the idle time out in IIS whichever comes first. Default is 20 minutes if I am not wrong

False

One application can have more than one WEB.config file but application root has only one. And any folder then we can add config file inside.

If we define same key in both config file then the config file inside the folder overrides the value of root config file.

No.The Repeater control is used to display a repeated list of items that are bound to the control. The Repeater control may be bound to a database table, an XML file, or another list of items.

Yes, repeater also have that capability to edit,delete and update the record.

We have to explicitly write the code for that, as we write for the binding of db.

Datalist is used to just read only purpose where data in table format. where a repeater has no such format to store the data. In repeater we can put data in any where in random format. The Repeater ...

You can use server.EncryptUrl , Server.DecryptUrl Functions.

client side session
server side session

1. Inproc
2. Out Proc
3. StateServer

Events available during page load are:

1.Pre-Init
2.Init
3.Initcomplete
4.PreLoad
5.Load
6.Loadcomplete
7.PreRender
8.Render

We are having 11 Page life cycle events.Below are the events occures during page load.1) Page_PreInit2) Page_Init3) Page_InitComplete4) Page_PreLoad5) Page_Load6) Page_LoadComplete7) Page_PreRender8)R...

if you want to Get Data Key value on Click of ImageButton/LinkButton, you can set the DataKey value to CommandArgument property of your control and then in Click handler you can get the value from CommandArgument property

Code
 <asp:ImageButton ID="ibtn" runat="server" CommandArgument=<%# Eval("DataKeyName")%>
 ImageUrl="~/Images/edit.png"></asp:ImageButton>
 

Basically this is the concept of control hierarchy works just the same with a DataGrid.

The passing of the control from the child to the parent is called as bubbling. Controls like DataGrid, Datalist, Repeater, etc can have child controls like Listbox, etc inside them. An event generated is passed on to the parent as an ItemCommand.

Caching on the web is that it avoids a roundtrip to the origin web server each time a resource is requested and instead retrieves the file from a local computers browser cache or a proxy cache closer to the user.

1. output caching
2. fragment caching
3. data caching

To Imporve the performance of Web Pages, we use Caching. Caching is a used for persisting data in memory for immediate acces to the program calls. It has three types : 1. Output Caching - to fetch ...

One reason is to avoid name collision or avoid the problem of Identity which can lead to collision in method overriding. However, please note that absolute multiple inheritance is not possible in C# but C# partially supports multiple inheritance via Interfaces.

Cookie is stored in client machine
Session is stored in server

Cookies : are stored in client side (User's browser) , Ideally suits for tiny data to be stored to be remembered by the browser where as Sessions : are variables stored in the web server to store data.

This is simple web chat application which will be used by people to talk about any job opening and interview related questions. It has two modules the login and the chat module. Login module consists ...

You can use socket programming for that.

Without web.config file, the application will be run but you cant debug.

Without machine.config file, you wont be run application because by default asp.net application used machine.config file settings.

If you remove web.config file the app will work provided that no connection string setting etc and other dependant dll. references is configured.

if you remove machine.config the app will not run