Interview Questions - Part 9

Interview Questions
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86. What is caching?
a ) This allows a way to keep most frequently used data in memory to increase the performance of the application.

87. What are the types of page output cache?
a ) This is used to store the contents of a processed page in memory.
It is devided in to 2 types
1. full page caching
it stores the entire contents of a page
2. partial page caching
it stores the parts of a page.

88. What do you mean by post-cache substitution?
a ) This is one type of partial page caching. It allows you to cache the entire page but parts of a page are not cached means they will be created dynamically.

89. When the items will be removed from the cache?
a ) Items from cache are removed
1. when memory runs low
2. when an item expires
3. when items dependency changes

90. What is Sliding expiration?
a ) Suppose an item is placed in cache and its sliding expiration is 10 minutes. Then this sliding expiration policy specifies that the item stored in cache will be removed after 10 min from the time it is last used/accessed.

91. What is Absolute expiration?
a ) Suppose an item is placed in cache and its absolute expiration is 5 pm. Then this absolute expiration policy specifies that the item will be removed from the cache after 5 pm.

92. What is the directive used to implement caching in a page?
a ) It is @OutputCache

93. What is the attribute used to set the expiration of an item in the cache?
a ) It is “Duration” attribute

94. What are the attributes of outputcache used to store multiple versions of a page?
a )
1. VaryByParam
Using querystring it enables you to cache multiple versions of a page
2. varyByControl
Using a control value it enables you to cache multiple versions of a page
3. VaryByHeader
Using requests http header it enables you to cache multiple versions of a page
4. VaryByCustom
Using custom string or browser type it enables you to cache multiple versions of a page

95. what is sql dependency in caching?
a ) Means an item in the cache depends on the changes in a table in sql Database.

Interview Questions - Part 7

Interview Question
--------------------------

66. What are the types of Serialization?
a ) 4 types
1. XML Serialization
2. Binary Serialization
3. SOAP Serialization
4. Custom Serialization

67. What is xml serialization?
a. ) Xml serialization can convert only the public properties and fields of an object in to an xml stream that confirms to a specific xml schema defination language document. Xml serialization is also known as shallow serialization. Xml serialization is used when you nedd the data in the object to stored in xml format. Xml stream can be processed by any application as needed regardless of platform.

68. What are the 2 methods of xmlserializer class?
a ) 1. serialize
2. deserialize

69. What is binary serialization?
a ) This is used to convert both public and private properties and fields of an object. This serialization is useful when data needs to travel electronically over wire. Disadvantage of this serialization is it is not easily portable to another platform.

70. What is SOAP Serialization?
a ) Similar to binary serialization this also convert the public and private properties and fields of an object in to a stream of bytes. This serialization is useful when you need interoperability.

71. what is satellite assembly?
a) An assembly which contains language specific resouces means culture information is known as satellite assembly.

72. what are the parts of version number of an assembly?
a) They are major, minor, revision, build.

73. what are the commands used to insert and remove assemblies in/from global assembly cache?
a) gacutil -I assemblyname /to insert
gacutil -u assemblyname /to uninstall

74. In which suituations we use gacutil tool?
a) We use it in development scenarios.

75. what is side-by-side execution?
a) This provides a way to keep multiple versions of an application on the same machine at the same time.

Interview Questions - Part 8

Interview Questions
---------------------------

76. What is the life time of the data stored in viewstate?
a ) Data stored in viewstate exists for the life of the current page.

77. Can a masterpage contain multiple content areas?
a ) Yes

78. What does the merge method of dataset do?
a ) It merges the dataset with another dataset.

79. What is the maximum length of the char datatype?
a ) Char – max of 8000 characters

80. What is the method used to kill a session explicitly?
a ) Session.abandon method.

81. What is the extension of the resource files?
a ) .resx

82. What is the attribute used to apply theme to a specific page?
a ) That is ‘Theme’ attribute.

83. How many types of configuration files are there?
a ) 2 types
Machine.config: This is a server or machine wide configuration file
Web.config : This is a application configuration file.

84. What are the advantages of web.config file?
a )
1. This contains application specific configuration settings whichis same for all the pages in that application.
2. This is xml file which is easily readble and understandable.
3. This applies changes to the asp.net application with out need for the administrator to stop and start the webserver.
4. It provides more security as data is encrypted.

85. Is it possible for an application to have more than one web.config file?
a ) Yes. An application can support more than one web.config file.

Interview Questions - Part 5

Interview Questions
------------------------

46. What is a command object?
a.) This is used to perform the required operations on the database. A command object contains 2 arguments. First argument specifies the sql statement or stored procedure to be executed on the database and second argument specifies the connection object. First argument, if it is a sql statement, it can be a select, update, insert or delete. If we want to use a stored procedure we should specify its name as the first argument of the command object. Command object is generally used along with the Data Reader.

47. Why we use ExecuteNonQuery method?
a.) This is the method of the connection object. This is used when you use a stored procedure. This won’t return any data from database, simply executes the procedure.

48. What is a DataAdapter?
a.) Dataset can’t communicate directly with the database. So, in order to communicate with the database it makes use of DataAdapter. This acts as a bridge between dataset and database. It contains 2 arguments. First argument specifies the sql statement , and 2 argument specifies the connection object. It can perform all the DML operations.

49. What is the method used by dataadapter to fill the dataset?
a.) It uses Fill() method to fill the dataset with data from database.

50. what are the differences between datareader and data adapter?
a.) DataReader:
1.It supports connected model
2.It is used to retrive a forward only read only stream of data from data source.
3.performance is more
4.It can not perform insert, delete or update operations
DataAdapter:
1.It supports Disconnected model
2.It acts as a bridge between dataset and database
3.performance is less when compared to datareader
4.It can perform insert, delete and update operations

51. How many templates are there in Repeater control?
a) 5 Templates are there
1. ItemTemplate
2. AlternatingItemTemplate
3. HeaderTemplate
4. FooterTemplate
5. SeparatorTemplate

52. What are the disadvantages of Repeater Control?
a )
1. It does not contain predefined layout.
2. It produces readonly output
3. It does not support user selection and editing of data
4. No inbuilt support for paging and sorting

53. How many templates are there in DataList Control
a ) 7 Templates
1. ItemTemplate
2. AlternatingItemTemplate
3. HeaderTemplate
4. FooterTemplate
5. SeparatorTemplate
6. SelectedItemTemplate
7. EditItemTemplate

54. What is the use of alternatingItem Template?
a ) This is used to apply alternate color scheme in Datareader and DataList server controls.

55. How many columns are there in DataGrid Control
a ) 5 columns
1. Bound Column
2. Button Column
3. Edit command column
4. Hyperlink Column
5. Templated Column

Interview Questions - Part 6

Interview Questions
-----------------------------

56. How can we customise columns in datagrid?
a ) Using the Template column.

57. What is the character/size limit in query string?
a ) Some browsers impose a 2083 character limit on the length of the URL.

58. How do you separate business logic while creating on asp.net application?
a ) By using code behind model

59. How many classes can a single .net dll contain?
a ) It can contain unlimitesd classes.

60. What is the maximum length of varchar and nchar datatypes?
a ) Varchar - max of 8000 characters
Nchar - max of 4000 characters

61. What is Portable Executable?
a ) It is a file format defining the structure that all executable files and dynamic link libraries must use to allow them to be loaded and executed by windows.

62. What is the use of Application Domain?
a ) This provides a way to isolate an application from other applications.

63. In which folder we store Local Resouce files?
a ) They are specific to a single page. They are stored in App_LocalResorces

64. What is serialization? What are its advantages?
a ) It provides a way to save the state of an object by converting it into a stream of bytes.
Advantages:
1. It provides a way to transportation of an object through a network
2. It provides a way to re create the same object by saving the its state.

65. What are the disadvantages of serialization?
a )
1. It requires more resources (to convert an object into a stream of bytes)
2. Serialization is a slow process.
3. It involves latency issues for transmitting the data over network.

Interview Questions - Part 3

Interview Questions
----------------------------

26. How many types of assemblies are there?
a. 2 Types.
1. Private assemblies: which are used by only one application and are placed in the application's directory
2. shared assemblies: which are shared by many applications and are placed in machine wide code cache called global assembly cache.

27. What are main contents of an assembly
a. They are 4 contents
1. assembly manifest
2. Type metadata
3. msil that implements types
4. list of resouces

28. What is an assembly manifest?
a. Assembly manifest is main part of an assembly. it is used to store information about metadata like version information, security information, types info, scope of assembly etc.

29. What are the contents of an assembly manifest?
a. It contains name of the assembly,version information, culture information, strongname information, type reference information, list of files in assembly, and list of other assemblies

30. What is a global assembly cache?
a. Using this you can place assemblies at one common place. this common place is known as global assembly cache. the advantage of this global assembly cache is that the assemblies placed in this common place can be shared by many applications. they are not restricted to a particular application. they can be shared by any application. when you place an assembly in to global assembly cache that assembly should have a strong name. Global assembly cache is placed in the subdirectory of the systemroot directory.

31. What are the ways to keep assemblies in to global assemby cache?
a. 3 ways.
1. using windows installer
2. using global assembly cache tool
3. using windows explorer

32. what is advantage of windows installer ?
a. This should be used in the deployment time. this provides reference counting of an assembly.

33. what is a strong name?
a. when you want to place assembly in global assembly cache you should give strong name to that assembly. It contains assembly name, its version, public key and digital signature.This is used to uniquely identify an assembly, and to perform integrity checks on assembly. It ensures that no one can create a subsequent version of an assembly.

34. what are the advantages of global assembly cache?
a. 1. assemblies placed in GAC can be shared by multiple applications.
2. It provides security.
3. It provides a way to keep multiple versions of same assembly on the same machine.

35. can we place the contents of an assembly into different files?
a. Yes.

Interview Questions - Part 4

Interview Questions
--------------------------------

36. what are the differences between Ado and Ado.net
a.) Ado:
1. It supports connected model
2. xml support is less
3. It uses record set
Ado.net
1. It supports disconnected model
2. xml support is more
3. it uses data set

37. What are the basic objects needed for Ado.Net
a.) There are 5 main objects.
1. Connection object: used to open a connection to the database
2. command object: used to perform operations on database
3. datareader object: used to read data in forward only read only manner from database
4. DataAdapter: Acts as a bridge between Dataset and Dataset
5. Dtaset: In-Memory container for all your data.

38. What are the arguments of a connection object?
a.) 1. server : this is used to specify the server name.
2. InitialCatalog: This is used to specify the database name
3. usedID: specifies the user id
4. password: specifies the user password.

39. Which method is used to release resources on connection object?
a.) Dispose() method.

40. What are the namespaces required to use Ado.net
a.) System
System.Data
System.Data.SqlClient (or) System.Data.OleDb (OR) system.Data.Odbc (OR) system.Data.OracleClient.

41. What is a Dataset?
a.) Dataset is a simple, in-memory data store for your data. It contains data, constraints on data, and relationships between data. It supports disconnected model, means connection is opened when the request is made and it closes when request is served with response. It can contain data from more than one table or database.

42. Why we use AcceptChanges method ?
a.) This is the method used by Dataset to commit the changes done by DML statements.

43. What is Getchanges method?
a.) This is used to get only those rows which have been modified. This can be used on a datatable or dataset.

44. What is a DataReader?
a.) DataReader is used to read data in forward only and read only manner.
Read() method is used to read data from database using datareader. They support connected model. Performance is more as they read data in forward only and read only manner. It can’t read data from more than one table at any point of time.

45. What are the methods we can apply on dataReader?
a.) 1.Read(): used to read
2.Close(): Used to close datareader
3.IsClosed(): used to check whether datareader is closed or not
4.HasRows(): used to check whether there are rows or not
5.NextResult(): with this we can execute a set of sql statements

Interview Questions - Part 2

Interview Questions
--------------------------
16. What is Global.asasx file?
a. This file contains application and session level events. It is an optional file. It is placed in the
root directory of the application.

17. what is the difference between inline and code behind models?
a. In inline model server code is written along with the html code.
in code behind model server side code is written in separate file having .aspx extension.

18. How many types of validation controls are there in asp.net?
there are 6 types of validation controls are there.
1.RequiredFieldValidator:
Used to ensure that there is an entry for a specified field.
2. CompareValidator:
Used to check users entry with a constant value or value of another control
3. RangeValidator:
Used to check whether users value is with in the specified range or not.
4. RegularExpressionValidator:
Used to check users entry against a pattern specified by regular expression.
5. CustomValidator:
Enables a user to specify his/her validation logic
6. ValidationSummary:
Used to display all the error messages at one place in a web page.

19. which directive do we use to add a custom or user control to a web page?
a. We use @Register control.

20. What is the extension and namespace for user controls?
a. User controls have .ascx extension and namespace is System.Web.UI.Usercontrol

21. What are master pages?
a. Master pages provide a uniform layout for all pages in your application. They are used to
create same look and feel for all pages.they provide a template which can be used by any
number of pages in an application. They have .master extension.

22. Is it possible to nest master pages?
a. Yes.

23. What is a wizard control?
a. This provides a way to create a sequence of steps which can be used by the user. This
control is useful in suituations where you want to split the information in to steps.
for ex. When you are registering in to any web site we can divide the information
collection process from the user in to 3 steps, step1 for login information, step 2 for
personal inrmation and step 3 for address information.

24. what is the method used to set focus on any control?
a. We use Focus() method.

25. what is smart navigation?
a. 1. It maintains same scroll position during postbacks.
2. used to keep element focus during navigation
3. used to minimise flash during navigation
4. only the most recent web page state is retained in the browsers history folder.

Interview Qusetions - Part 1

Interview Questions
---------------------------

1. What is a private assembly?
a. An assembly which is used by only one application and which is placed in the installation directory of an application.

2. what is MSIL?
a. When we compile a c# program or any other program written in .net complaint languages, the source code is compiled in to MSIL. It is an instruction set in to which all .net prgrams are compiled and which is used by the CLR. It contains instruction for loading, storing, initializing, and calling methods.

3. What is CTS?
a. CTS means common type system. It defines how types are declared, used and managed in the runtime. This supports a variety of types and operations found in most of the programming languages and therefore calling one language from another does not require type convertions.

4. What is CLS?
a. CLS means common language specification. This enables interoperability in the .net platform.

5. What is JIT?
A. It is a compiler that converts MSIL to native code.

6. why do we use namespaces?
a. Namespaces are used to organise the code and to create globally unique types to avoid name collisions.

7. What is web farm?
a. Asp.net runs with in a process known as asp.net worker process. All asp.net functionality runs with in the scope of this process. A regular web server contains only a single asp.net worker process. A web farm contains multiple asp.net worker processes. Generally normal(small) web sites uses a single web server to satisfy the user requests. but a web farm(larger web sites) uses one or more seb servers to satisfy the user requests.

8. What is Globalization?
a. It is the process of design and development of applications that serve multiple cultures.

9. What is Localization?
a. It is a process of customizing an application for a given culture and locale.

10. What is a Thread?
a. A thread is a basic unit to which operating system allocates processor time. One process can have more than one thread. Each thread maintains exception handlers, scheduling priorities, and a set of structures the system uses to save the thread context until it is scheduled.

11. Differences between managed code and unmanged code?
Managed code:
1.It is executed under CLR.
2.It compiles to intermediate language
3. it provides services like security, exception handling, garbage collection etc
4. It can access both managed and unmanaged data
unmanaged code :
1. It is not executed under CLR.
2. It compiles directly to machine code.
3. It doen not provide security, exception handling, garbage collection etc
4. It can access only unmanaged data.

12. What is a bin directory?
a. It contains precompiled assemblies. this is useful when you need to use code that is possibly written by someone else where you don't have access to the source code but you have a compiled dll instead.

13. What is the use of enableviewstatemac property?
a. This is the attribute of a @page directive. This is used to check whether the view state has been tampered or not.

14. How to change a master page during rntime?
a. This is possible in the PreInit() event by setting MasterPageFile property to .master page.

15. What is serialization?
a. It is a process of saving the state of an object by converting it to a stream of bytes. the object can then be persisted to a file, database, or even memory.