MVC Routing Concept

URL stand for Uniform Resource Locator
for example www.abc.com/directory/emplyee.htm

URI is an identifier for some resource, but a URL gives you specific information as to obtain that resource.URL doesn’t necessarily mean a physical location of a static file on a web server’s
hard drive somewhere ,it means some unique identifier.

Most of the cases Webserver  and then directory and sub directory and file name

But in MVC the method is different

1. MVC matches controller action rather than file system
2. MVC also matches outgoing request with  controller action rather than file system

Route definitions start with the URL pattern, which specifies the pattern that the route will match. Along with the route URL, routes can also specify default values and constraints for the various parts of the URL, providing tight control over how and when the route matches incoming request URLs


Application_Start()   method contains a call to a method named the
RegisterRoutes method


 public static void  RegisterRoutes (  RouteCollection routes  )
{
      routes.MapRoute( “example”, “{first}/{second}/{third}”);
}

Routing: /albums /display/123
Result: first = “albums” second = “display” third = “123”
routes.MapRoute(“simple”, “{first}/{second}/{third}”);

The {action} parameter value is used to indicate which method of the controller to call in order
to handle the current request. Note that this method invocation applies only to controller classes
that inherit from the System.Web.Mvc.Controller base class. Classes that directly implement
IController can implement their own conventions for handling mapping code to handle the
request.

Any route parameters other than {controller} and {action} can be passed as parameters to the
action method, if they exist. For example, assuming the following controller:

public class AlbumsController : Controller
{
            public ActionResult Display(int id)
           {
                return View();
            }
}

ROUTE URL PATTERN                           EXAMPLES OF URLS THAT MATCH
{controller}/{action}/{genre}                      /albums/list/rock
service/{action}-{format}                            /service/display-xml
{report}/{year}/{month}                              /{day} /sales/2008/1/23

routes.MapRoute(“simple”, “{controller}/{action}/{id}”,new {id = UrlParameter.Optional});


Multiple default values can be provided. The following snippet demonstrates providing a default
value for the {action} parameter as well:
routes.MapRoute(“simple”, “{controller}/{action}/{id}”, new {id = UrlParameter.Optional, action=”index”});

using System.Web.Routing;

SQL Server 2012 Magic

1)Unusual Sort Orders
         (Order by Contain Case)

SELECT  certificate_id,
                certificate_name,
                certificate_code,
                type_id,
               date_position
                              FROM tbl_sref_train_certificate
                             ORDER BY
                                     CASE date_position WHEN NULL
                                        THEN type_id
                                   ELSE  date_position  END

2) NULLIF,COALESCE

ISNULL : Returns a null value if the two specified expressions are equal.

SELECT NULLIF(2,2)

Result
----------------------------------------
 NULL

SELECT NULLIF(2,3) 
Result
----------------------------------------
2

COALESCE : coalesce returns the first non-null expression among its arguments.

Example 1
SELECT COALESCE(NULL, NULL, NULL, GETDATE()) 

Result
----------------------------------------
2014-11-02 22:48:40.780

The above example may have single value or four values. If it has single value, then it fills null values with remaining attributes.

---------------------------------------------------------------
column 1              |     column1
----------------------------------------------------------------
 Abc                          NULL
NULL                      Efg
--------------------------------------------------------------

Example 2
 SELECT COALESCE(column 1, column1 )

Result
----------------------------------------
  Abc
 Efg

Example 3
Concatination

---------------------------------------------------------------
Country              |     Currency
----------------------------------------------------------------
India                          Rupee
Japan                         Yen
--------------------------------------------------------------


SELECT  Country ,
                 Currency,
                 COALESCE(Country,Currency)  As Country_Currency

---------------------------------------------------------------
Country              |     Currency     | Country_Currency
----------------------------------------------------------------
India                          Rupee           India Rupee          
Japan                         Yen               Japan Yen                              
--------------------------------------------------------------

3) UNION AND UNION Goof Exapmle

DECLARE @test1 TABLE
(
  ID INT,
  NAME VARCHAR(200)
)
DECLARE @test2 TABLE
(
  ID INT,
  NAME VARCHAR(200)
)

INSERT INTO @test1 VALUES (1,NULL),(2,'India'),(3,'Japan'),(4,NULL)
INSERT INTO @test1 VALUES (1,NULL),(2,'USA'),(3,'Braziln'),(4,NULL),(1,'India')

SELECT ID,NAME FROM @test1
UNION
SELECT ID,NAME FROM @test2

SELECT ID,NAME FROM @test1
UNION ALL
SELECT ID,NAME FROM @test2

Result
----------------------------------------
ID NAME
-----------------------------------------
1    NULL
1    India
2    India
2    USA
3    Braziln
3    Japan
4    NULL

Result
----------------------------------------
ID NAME
-----------------------------------------
1    NULL
2    India
3    Japan
4    NULL
1    NULL
2    USA
3    Braziln
4    NULL
1    India

4)Random Rows Return

SELECT  member_id,
        last_name,
        first_name
 FROM tbl_member
 TABLESAMPLE SYSTEM (1 PERCENT);

Result (1st Execution)
----------------------------------------
102  rows

Result (2st Execution)
----------------------------------------
106  rows

So on...

5)Overriding an IDENTITY Column

CREATE TABLE TEST
(
    ID INT IDENTITY  ,
    COUNTRY VARCHAR(200)
)

INSERT INTO TEST (COUNTRY) VALUES ('India'),('Brazil'),('China')

SELECT * FROM TEST

Result
----------------------------------------
ID NAME
-----------------------------------------
1    India
2    Brazil
3    China



SET IDENTITY_INSERT [Database].TEST
INSERT INTO TEST (COUNTRY) VALUES (4,'Pakistan'),(5,'Irac')


----------------------------------------
ID NAME
-----------------------------------------
1    India
2    Brazil
3    China
4   Pakistan
5   Irac


6) Deleting Rows and Returning the Deleted Rows

CREATE TABLE TEST
(
    ID INT IDENTITY  ,
    COUNTRY VARCHAR(200)
)

INSERT INTO TEST (COUNTRY) VALUES  ( 'India' ),( 'Brazil'  ),(  'China'  ),(  'Nepal'  )

DELETE
FROM TEST
OUTPUT deleted.COUNTRY
WHERE ID=4

7) Inserting Rows and Returning the Inserted Rows

CREATE TABLE TEST
(
    ID INT  ,
    COUNTRY VARCHAR(200)
)

INSERT INTO TEST (ID,COUNTRY)
OUTPUT INSERTED.COUNTRY,INSERTED.ID
VALUES       (1,'India')  ,  (2,'Brazil')  ,  (3,'China')  ,  (4,'Nepal')

8)Updating Data and Returning the Affected Rows

CREATE TABLE TEST
(
    ID INT  ,
    COUNTRY VARCHAR(200)
)

INSERT INTO TEST (ID,COUNTRY)
VALUES (1,'India') , (2,'Brazil') , (3,'China') , (4,'Nepal')


CREATE TABLE TEST1
(
    ID INT  ,
    COUNTRYX VARCHAR(200) NULL
)

INSERT INTO TEST1
VALUES (1,NULL),(2,NULL),(3,NULL),(4,NULL)

SELECT * FROM TEST1

UPDATE A
           SET A.COUNTRYX=B.COUNTRY
           OUTPUT INSERTED.COUNTRYX
FROM  TEST1 A
INNER JOIN TEST B
ON A.ID=B.ID

SELECT * FROM TEST1


9) SoundIndex ...Sound Like

DROP TABLE TEST

CREATE TABLE TEST
(
    ID INT  ,
    COUNTRY VARCHAR(200)
)

INSERT INTO TEST (ID,COUNTRY)
VALUES (1,'India'   )  ,
                (2,'Brazil'  )  ,
                (3,'China'  )  ,
                (4,'Nepal'  )  ,
                (5,'ian'      )  ,
                (6,'en'       )  ,
                (7,'an'       )  ,
                (8,'am'      ) ,
                (9,'em'      ),
                (10,'am'    )



SELECT  top 5 COUNTRY
FROM TEST
WHERE  SOUNDEX(COUNTRY)=SOUNDEX('inI')

Result
----------------------------------------
COUNTRY
-----------------------------------------
ian


10) Merger Statement

CREATE TABLE TEST
(
    ID INT  ,
    COUNTRY VARCHAR(200)
)

INSERT INTO TEST (ID,COUNTRY)
VALUES    (1,'India'),
                   (2,'Brazil'),
                   (3,'China'),
                   (4,'Nepal'),
                   (5,'ian'),
                   (6,'en'),
                   (7,'an'),
                   (8,'am'),
                   (9,'em'),
                   (10,'am')


CREATE TABLE TEST1
(
    ID INT  ,
    COUNTRYX VARCHAR(200) NULL
)


MERGE INTO TEST1 AS C
USING TEST AS CT
        ON C.ID = CT.ID
WHEN MATCHED THEN
    UPDATE SET
      C.COUNTRYX = CT.COUNTRY    
WHEN NOT MATCHED THEN
      INSERT (ID,COUNTRYX)
      VALUES (CT.ID, CT.COUNTRY);
     
SELECT * FROM TEST1

---------------------------------------------------------------------------------
ID COUNTRYX
----------------------------------------------------------------------------------
1    India
2    Brazil
3    China
4    Nepal
5    ian
6    en
7    an
8    am
9    em
9    am

11) Sring Operation 

LEFT & RIGHT

SELECT LEFT  (  'India Govt has started clean india mission.' , 10)
SELECT RIGHT ( 'India Govt has started clean india mission.' , 10) ;

Result
----------------------------------------
(No column name)
-----------------------------------------
 India Govt


Result
----------------------------------------
(No column name)
-----------------------------------------
a mission.


UPPER & LOWER 

SELECT UPPER ( 'India Govt has started clean india mission. '  )
SELECT LOWER (  'India Govt has started clean india mission.'  )

Result
----------------------------------------
(No column name)
-----------------------------------------
 INDIA GOVT HAS STARTED CLEAN INDIA MISSION.


Result
----------------------------------------
(No column name)
-----------------------------------------
india govt has started clean india mission.


12) Date Function

ISDATE :valid date or not

 SELECT MyDate ,ISDATE(MyDate) AS IsValiDate
                                    FROM (
                                                 VALUES(  'IsValiDate'   ),
                                                                (  '2012-02-14' ),
                                                                (  '2012-01-01T00:00:00'  ),
                                                                (  '2014-12-31T23:59:59.9999999' )
                                               )   dt(MyDate)

 
Result
--------------------------------------------------------------------------------------------
MyDate                                    |                    IsValiDate
-------------------------------------------------------------------------------------------
 IsValiDate                                                              0
2012-02-14                                                             1
2012-01-01T00:00:00                                            1
2014-12-31T23:59:59.9999999                             0

13) @@IDENTITY && SCOPE_IDENTITY 

@@IDENTITY returns the last identity value generated by any table in the current session. If the insert statement fires a trigger that inserts into another table with an identity column, the value returned by @@IDENTITY will be that of the table inserted into by the trigger.
SCOPE_IDENTITY returns the last identity value generated by any table in the current session and scope. In the previous scenario, SCOPE_IDENTITY returns the identity value returned by the first insert statement, not the insert into the second table from the trigger.

CREATE TABLE TEST
(
    IDX INT IDENTITY ,
    ID INT  ,
    COUNTRY VARCHAR(200)
)

INSERT INTO TEST (ID,COUNTRY)
VALUES    (1  ,  'India'  ),
                   (2  ,  'Brazil' ),
                   (3  ,  'China' ),
                   (4  ,  'Nepal' ),
                   (5  ,  'ian'     ),
                   (6  ,  'en'      ),
                   (7  ,  'an'     ),
                   (8  ,  'am'    ),
                   (9  ,  'em'   ),
                   (10 , 'am'   )

 SELECT @@IDENTITY, SCOPE_IDENTITY(), IDENT_CURRENT('dbo.TEST');

14) ESCAPE 

 SELECT access_name FROM tbl_user
 WHERE  access_name LIKE  '%%%' 












all ,value return , no match for wildcard %

Instead, you can try one of the following solutions:

SELECT access_nameFROM tbl_userWHERE 
    access_name LIKE  '%[%]%' 
 

SELECT access_name FROM tbl_user  WHERE
    access_name LIKE '%\%%' ESCAPE '\'

CLASS

1) What is Class ?
           A class is the blueprint from which individual objects.

2) What is constructor ?
A constructor in a class is a special type of subroutine called to create an object. It prepares the new object for use

 class Sample

{

             public string param1, param2;

             public Sample()     // Default Constructor

            {

              param1 = "Welcome";

              param2 = "Aspdotnet-Suresh";

            }

}
 

class Program

{

           static void Main(string[] args)

            {

                      Sample obj=new Sample();   // Once object of class created automatically constructor will be called

                    Console.WriteLine(obj.param1);

                    Console.WriteLine(obj.param2);

                    Console.ReadLine();

            }

}

3) Private & Public & Protected ?

Private :Variables and methods declared with private visibility are not accessible in the child class

Public :Variables and methods declared with public visibility are accessible; but public variables violate our goal of encapsulation

Protected : Variables and methods declared with protected visibility in a parent class are only accessible by a child class or any class derived from that class

4) What is Inheritance ?

Inheritance is when an object or class is based on another object or class, using the same implementation

public class ParentClass
{
           public ParentClass()
           {
           }
           public void print()
           {
        Console.WriteLine("I'm a Parent Class.");
          } 
}

 public class ChildClass : ParentClass
{
    public ChildClass()
    {
        Console.WriteLine("Child Constructor.");
    }

    public static void Main()
    {
        ChildClass child = new ChildClass();
        child.print();
    }
}

5) What is sealed class ?
A sealed class is a class that cannot be inherited. Sealed classes are used to restrict the inheritance

    sealed class SealedClass
    {
        public int x;
        public int y;
    }

6)What is interface ?

An interface contains only the signatures of methods, properties, events or indexers. A class or struct that implements the interface must implement the members of the interface that are specified in the interface definition
 
Using interfaces we can invoke functions from different classes through the same Interface reference, whereas using virtual functions we can invoke functions from different classes in the same inheritance hierarchy through the same reference

interface ISampleInterface
{
    void SampleMethod();
}

class ImplementationClass : ISampleInterface
{
    // Explicit interface member implementation:  
    void ISampleInterface.SampleMethod()
    {
        // Method implementation.
    }

    static void Main()
    {
        // Declare an interface instance.
        ISampleInterface obj = new ImplementationClass();

        // Call the member.
        obj.SampleMethod();
    }
}

7)What is Abstact Class ?

They are classes that cannot be instantiated, and are frequently either partially implemented, or not at all implemented

//Abstract Class1
abstract class absClass1
{
    public abstract int AddTwoNumbers(int Num1, int Num2);
    public abstract int MultiplyTwoNumbers(int Num1, int Num2);
}

//Abstract Class2
abstract class absClass2:absClass1
{
    //Implementing AddTwoNumbers
    public override int AddTwoNumbers(int Num1, int Num2)
    {
        return Num1+Num2;
    }
}

//Derived class from absClass2
class absDerived:absClass2
{
    //Implementing MultiplyTwoNumbers
    public override int MultiplyTwoNumbers(int Num1, int Num2)
    {
        return Num1*Num2;
    } 

} 

8) Abstact Class Vs Interface

Interfaces	Abstract Classes
A class may inherit several interfaces.	A class may inherit only one abstract class.
Interfaces can only have consts and methods stubs	Abstract classes can have consts, members, method stubs and defined methods, whereas
All methods of an interface must be defined as public	Methods and members of an abstract class can be defined with any visibility
An interface cannot have access modifiers for the subs, functions, properties etc everything is assumed as public	An abstract class can contain access modifiers for the subs, functions, properties

9) Output Parameter C#

   public void getValues(out int x, out int y )
      {
          Console.WriteLine("Enter the first value: ");
          x = Convert.ToInt32(Console.ReadLine());
          Console.WriteLine("Enter the second value: ");
          y = Convert.ToInt32(Console.ReadLine());
      }
   

        /* local variable definition */
         int a , b;
         
         /* calling a function to get the values */
         n.getValues(out a, out b);

10) Event & Delegates

Delegate and Event concepts are completely tied together. Delegates are just function pointers, That is, they hold references to functions.


11) Override

override stands for use one's authority to reject or cancel

abstract class ShapesClass
{
    abstract public int Area();
}
class Square : ShapesClass
{
    int side = 0;

    public Square(int n)
    {
        side = n;
    }
    public override int Area()
    {
        return side * side;
    } 

} 

12)Overloading

mechanism to have more than one method with same name but with different signature (parameters). A method can be overloaded on the basis of following properties

1. Have different number of parameter
2. Having same number of parameters but of different type
3. Having same number and type of parameters but in different orders

public class test
{
    public void getStuff(int id)
    {}
    public void getStuff(string name)
    {}
}

13)What is virtual keyword ?
 
            The virtual keyword is used to modify a method, property, indexer, or event declaration   and allow for it to be overridden in a derived class. For example, this method can be overridden by any class that inherits it.

      When a virtual method is invoked, the run-time type of the object is checked 

for an overriding member. The overriding member in the most derived class is 

called, which might be the original member, if no derived class has overridden 

the member.

        class A
        {
           public virtual void Test()
           {
         Console.WriteLine("A.Test");
           }
        }

         class B : A
         {
          public override void Test()
          {
     Console.WriteLine("B.Test");
          }
         }

14)