GridView, DataList, ListView, Repeater

what is the difference between GridView, DataList, ListView, Repeater, DetailsView, FormView in asp.net?

Here I will show what are the inbuilt functionality provided by controls this will be answer to your question what is the difference between GridView, DataList, ListView, Repeater, DetailsView, FormView in asp.net?

following tales are inbuilt one if its not there you can implement by custom way.

Control	Paging	Sorting	Grouping	Insert	Update	Delete
Gridview	Yes	Yes	No	Yes	Yes	Yes
ListView	Yes	Yes	Yes	Yes	Yes	Yes
DataList	No	No	No	Yes	Yes	Yes
DetailsView	Yes	No	Single Record:Yes	Yes	Yes	Yes
FormView	Yes	No	Single Record:Yes	Yes	Yes	Yes
Repeater	No	No	Single Record:Yes	No	No	NO

ASP.NET Page Life Cycle

You should look at this ASP.NET Page Life Cycle Overview and this

Page: PreInit
Control: Init
Page: Init
Page: InitComplete
Page: PreLoad
Page: Load
Control: Load
Page: LoadComplete
Page: PreRender
Control: PreRender
Page: PreRenderComplete
Page: SaveStateComplete
Page: RenderControl
Page: Render
Control: RenderControl
Control: Unload
Control: Dispose
Page: Unload
Page: Dispose

Entity Framework in .Net

What is Entity Framework?

Writing and managing ADO.Net code for data access is tedious and monotono job. Microsoft has provided an O/RM framework called "Entity Framework" to automate database related activities for your application.

Microsoft has given following definition of Entity Framework:

The Microsoft ADO.NET Entity Framework is an Object/Relational Mapping (ORM) framework that enables developers to work with relational data as domain-specific objects, eliminating the need for most of the data access plumbing code that developers usually need to write. Using the Entity Framework, developers issue queries using LINQ, then retrieve and manipulate data as strongly typed objects. The Entity Framework's ORM implementation provides services like change tracking, identity resolution, lazy loading, and query translation so that developers can focus on their application-specific business logic rather than the data access fundamentals.

Entity framework is an Object/Relational Mapping (O/RM) framework. It is an enhancement to ADO.NET that gives developers an automated mechanism for accessing & storing the data in the database.

Entity framework is useful in three scenarios. First, if you already have existing database or you want to design your database first than other parts of the application. Second, you want to focus on your domain classes and then create the database from your domain classes. Third, you want to design your database schema on the visual designer and then create the database and classes.

What is O/RM?

ORM is a tool for storing data from domain objects to relational database like MS SQL Server, in an automated way, without much programming. O/RM includes three main parts: Domain class objects, Relational database objects and Mapping information on how domain objects map to relational database objects (tables, views & storedprocedures). ORM allows us to keep our database design separate from our domain class design. This makes the application maintainable and extendable. It also automates standard CRUD operation (Create, Read, Update & Delete) so that the developer doesn't need to write it manually.

ASP.NET Page Life Cycle Events

ASP.NET Page Life Cycle Events

At each stage of the page life cycle, the page raises some events, which could be coded. An event handler is basically a function or subroutine, bound to the event, using declarative attributes such as Onclick or handle.

Following are the page life cycle events:

• PreInit - PreInit is the first event in page life cycle. It checks the IsPostBack property and determines whether the page is a postback. It sets the themes and master pages, creates dynamic controls, and gets and sets profile property values. This event can be handled by overloading the OnPreInit method or creating a Page_PreInit handler.
• Init - Init event initializes the control property and the control tree is built. This event can be handled by overloading the OnInit method or creating a Page_Init handler.
• InitComplete - InitComplete event allows tracking of view state. All the controls turn on view-state tracking.
• LoadViewState - LoadViewState event allows loading view state information into the controls.
• LoadPostData - During this phase, the contents of all the input fields are defined with the <form> tag are processed.
• PreLoad - PreLoad occurs before the post back data is loaded in the controls. This event can be handled by overloading the OnPreLoad method or creating a Page_PreLoad handler.
• Load - The Load event is raised for the page first and then recursively for all child controls. The controls in the control tree are created. This event can be handled by overloading the OnLoad method or creating a Page_Load handler.
• LoadComplete - The loading process is completed, control event handlers are run, and page validation takes place. This event can be handled by overloading the OnLoadComplete method or creating a Page_LoadComplete handler
• PreRender - The PreRender event occurs just before the output is rendered. By handling this event, pages and controls can perform any updates before the output is rendered.
• PreRenderComplete - As the PreRender event is recursively fired for all child controls, this event ensures the completion of the pre-rendering phase.
• SaveStateComplete - State of control on the page is saved. Personalization, control state and view state information is saved. The HTML markup is generated. This stage can be handled by overriding the Render method or creating a Page_Render handler.
• UnLoad - The UnLoad phase is the last phase of the page life cycle. It raises the UnLoad event for all controls recursively and lastly for the page itself. Final cleanup is done and all resources and references, such as database connections, are freed. This event can be handled by modifying the OnUnLoad method or creating a Page_UnLoad handler.

Stored Procedure and Functions

	Stored Procedure	Functions
Compilation	Stored in database in compiled format. Note: Compiled indicates, Execution plan will be made by sql at the time it created and stored in DB.	Will compiled at run time
Return type	It can directly return only integers Return type is not must	It can return any scalar or table Return type is must
Multiple return values	It can also return more than one values (of any data type) indirectly with the help of out parameters	It won't support out parameters
DML Statements	Can have DML statements.	Cannot have DML statements. Note: In case of multi-table valued functions it can contain DML statements affecting Table Variables.
Execution	Stored procedure can execute function. Cannot be the part of Select query as a column. Stored Procedures cannot be used in the SQL statements anywhere in the WHERE/HAVING/SELECT	Function cannot execute stored procedure. Can be the part of select query as a column. Functions be used in the SQL statements anywhere in the WHERE/HAVING/SELECT
Exception handling	Can have Try....Catch	Cannot have Try....Catch

Database objects

Table

Data types

Function

Index

Constraint

Rule

Default

Stored Procedures

Trigger

View

Define database objects. Table SQL Server database stores information in a two dimensional objects of rows and columns called table.

Data types

Data types specify the type of data that can be stored in a column.
Data types are used to apply data integrity to the column.
SQL Server supports many data type like character, varchar, integer, binary, decimal, money etc.
You can also create you own data type (User defined datatype) using system data type.

Function

Microsoft SQL server allows you to create functions.
These functions are known as User Defined Functions.
It represents business logic using one or more transact SQL statements.
It can accept parameter(s) and can return scalar data value or a table data type.
It can be used in the SQL statement which is added advantage over stored procedure.

Index

Index can be thought as index of the book that is used for fast retrieval of information.
Index uses one or more column index keys and pointers to the record, to locate record.
Index is used to speed up query performance.
Kind of the indexes are clustered and non-clustered. Both exist as B-tree structure.

Clustered index exists as sorted row on disk.
Clustered index re-orders the table record.
Clustered index contains record in the leaf level of the B-tree.
There can be only one Clustered index possible in a table.

Non-clustered is the index in which logical order doesn’t match with physical order of stored data on disk.
Non-clustered index contains index key to the table records in the leaf level.
There can be one or more Non-clustered indexes in a table.

Unique index is the index that is applied to any column of unique value.
A unique index can also be applied to a group of columns.

Constraint

Using Constraint, SQL Server enforces the integrity to the database.
It defines the rules that restrict unwanted data in the column.
Constraints can be table constraints or column constraints.

Primary Key ConstraintIt is defined for one column or more columns that ensure data within these columns uniquely identify each row of the table. Primary key column doesn’t allow null value. It doesn’t allow duplicate data in the table.

Foreign Key Constraint Foreign Key is to create link between two tables. It creates parent-child relationships. It ensures that data from parent can be deleted only when there is no corresponding data in the child.

Unique Key ConstraintUnique key constraint is also like primary key except it allows null value to the column with unique key constraints.

Check Key Constraint It enforces domain integrity by restricting unwanted data to the column.

Rule

Rule is older version of check function. You can apply only one rule to the column. You should first create rule using ‘Create Rule’ statement and then bind the rule to the column using sp_bindrule system stored procedure.

Default

It ensures default value to the column if you do not specify a value to the column while inserting a row.

Stored Procedures

A stored procedure is a compiled set of Transact-SQL statements.
The business logic can be encapsulated using stored procedure.
It improves network traffic by running set of Transact-SQL statements at one go.

Trigger

A trigger is a special type of event driven stored procedure.
It gets initiated when Insert, Delete or Update event occurs.
It can be used to maintain referential integrity.
A trigger can call stored procedure.

View

View can be created to retrieve data from one or more tables.
Query used to create view can include other views of the database.
We can also access remote data using distributed query in a view.

Data Integrity Data Integrity validates the data before getting stored in the columns of the table. SQL Server supports four type of data integrity: Entity Integrity Entity Integrity can be enforced through indexes, UNIQUE constraints and PRIMARY KEY constraints.

Domain Integrity

Domain integrity validates data for a column of the table.
It can be enforced using:

Foreign key constraints,
Check constraints,
Default definitions
NOT NULL.

Referential Integrity

FOREIGN KEY and CHECK constraints are used to enforce Referential Integrity.

User-Defined Integrity

It enables you to create business logic which is not possible to develop using system constraints. You can use stored procedure, trigger and functions to create user-defined integrity.

Difference between WCF and ASP.NET Web Service

Difference between WCF and ASP.NET Web Service

WCF

ASP.NET Web Service

ServiceContract and OperationContract attributes are used for defining WCF service.

WebService and WebMethod attributes are used for defining web service.

Supports various protocols like HTTP, HTTPS, TCP, Named Pipes and MSMQ.

Supports only HTTP, HTTPS protocols.

Hosted in IIS, WAS (Windows Activation Service), Self-hosting, Windows Service.

Hosted only in IIS.

Supports security, reliable messaging, transaction and AJAX and REST supports.

Support security but is less secure as compared to WCF.

Supports DataContract serializer by using System.Runtime.Serialization.

Supports XML serializer by using System.Xml.Serialization.

Supports One-Way, Request-Response and Duplex service operations.

Supports One-Way and Request-Response service operations.

WCF are faster than Web Services.

Web Services are slower than WCF

Hash Table can be serialized.

Hash Table cannot be serialized. It can serializes only those collections which implement IEnumerable and ICollection.

Unhandled Exceptions does not return to the client as SOAP faults. WCF supports better exception handling by using FaultContract.

Unhandled Exceptions returns to the client as SOAP faults.

Supports XML, MTOM, Binary message encoding.

Supports XML and MTOM (Message Transmission Optimization Mechanism) message encoding.

Supports multi-threading by using ServiceBehaviour class.

Doesn’t support multi-threading.