While Loop

//Now let us see how the while loop works
using System;

namespace whileloop

{

class cl1

{

static void Main()

{

int i=0,j,sum=0;

Console.WriteLine("Enter 10 No.s");

while(i<10)

{

j=Convert.ToInt32(Console.ReadLine());

sum=sum+j;

i++;

}

Console.WriteLine("Sum="+sum);

}

}

}

Looping Statements

Let us consider acondition where we have to get a 100 numbers.These codes can sill be length like
inum1=Convert.ToInt32(Console.ReadLine());
inum2=Convert.ToInt32(Console.ReadLine());
inum3=Convert.ToInt32(Console.ReadLine());
inum4=Convert.ToInt32(Console.ReadLine());
inum5=Convert.ToInt32(Console.ReadLine());
inum6=Convert.ToInt32(Console.ReadLine());
.
.
.
.
inum100=Convert.ToInt32(Console.ReadLine());
so to over come these problem we are using the loop sattements....Here we will use a loop statement the body will be executed until the condition turns false

Arithmetic operators with switch

// Again one more switch condition statement....

using System;

namespace symbols

{

class class1

{

static void Main()

{

char ch;

int inum1,inum2,inum3;

double dnum;

Console.WriteLine("Enter first nmber");

inum1=Convert.ToInt32(Console.ReadLine());

Console.WriteLine("Enter second nmber");

inum2=Convert.ToInt32(Console.ReadLine());

Console.WriteLine("Enter your choice + , - , * or /");

ch=Convert.ToChar(Console.ReadLine());

switch(ch)

{

case '+' :

inum3=inum1+inum2;

Console.WriteLine("Sum is "+inum3);

break;

case '-' :

inum3=inum1-inum2;

Console.WriteLine("Difference is "+inum3);

break;

case '*' :

inum3=inum1*inum2;

Console.WriteLine("Product is "+inum3);

break;

case '/' :

dnum=(Double)(inum2/inum1);

Console.WriteLine(" Quotient is "+dnum.ToString());

break;

default :Console.WriteLine("entered a wrong choice");

break;

}

}

}

}

switch statements

/*Now let us see the multiple selection statements ,for these pourpose we can use switch statements

syntax :- switch(expression)

{

case value1:

body;

break;

case value2:

body;

break;

case value3:

body;

break;

default :

body;

break; //executes if all other conditions are wrong....

*/

using System;

namespace switchdemo

{

class class1

{

static void Main()

{

char ch;

Console.WriteLine("enter your choice (a,b,c,d)");

ch=Convert.ToChar(Console.ReadLine());

switch(ch)

{

case 'a' :

Console.WriteLine("This is from case a");

break;

case 'b' :

Console.WriteLine("This is from case b");

break;

case 'c' :

Console.WriteLine("This is from case c")

;

break;

case 'd' :

Console.WriteLine("This is from case d");

break;

default :

Console.WriteLine("This not from the specified choice");

break;

}

}

}

}

Conditional Statements

/ *Now we are going to see the conditional statements in this we canspecify a particular condition for executing one or more statements

Syntax:-

if(condition)

{

body

}

else if(condition)

{

body

}

else{

body

}
*/
using System;

namespace condition{

class class1

{

static void Main()

{

int inum1;

Console.WriteLine("enter a no between 1 to 100");

inum1=Convert.ToInt32(Console.ReadLine());

if (inum1<=10)

{

Console.WriteLine("the number you have entered is less than 10");

}

else if (inum1>10&&inum1<50)

{

Console.WriteLine("the number you have entered is less than 50 but more than 10");

}

else

{

Console.WriteLine("the number you have entered is more than 10");

}

}

}

}

Double...

In this program lets see how to convert to double

using System;

namespace doubledemo

{

class class1

{

static void Main()

{

double inum1,inum2,add;

Console.WriteLine("enter a no");

inum1=Convert.ToDouble(Console.ReadLine());

Console.WriteLine("enter a second no.");

inum2=Convert.ToDouble(Console.ReadLine());

add=inum1+inum2;

Console.WriteLine("Result ="+add.ToString());

}

}

}

converting to character

/ /converting to character .......

using System;

namespace nm1

{

class cl1

{

static void Main()

{

char ch;
Console.WriteLine("enter a character");

ch=Convert.ToChar(Console.ReadLine());

Console.WriteLine("The character entered is "+ ch);
}

}

}

/* Here we are going to add two numbers */
using System;

namespace nm1

{

class cl1

{

static void Main()

{

int inum1,inum2,add;

Console.WriteLine("enter a no");

inum1=Convert.ToInt32(Console.ReadLine());

Console.WriteLine("enter a second no.");

inum2=Convert.ToInt32(Console.ReadLine());

add=inum1+inum2;

Console.WriteLine("Result ="+add.ToString());

}

}

}

convert To Int

Lets try converting the program from string to int,float ,double,char

To interger "Convert.ToInt32(inputed value)";

To float we use "float.Parse(inputed value)",

To double "Convert.ToDouble(inputed value)",

To Character "Convert.ToChar(inputed value)"

using System;

namespace name1

{

class cls1

{

static void Main()

{

String str;

int inum;

Console.WriteLine(" Enter a number");

str=Console.ReadLine();

inum=Convert.ToInt32(str); // Here we are converting

Console.WriteLine("The numbe entred is "+inum);

}

}

}

Input

In this program we are discussing how to give an input . For getting the input we are using the command "Console.ReadLine()".The input we got will be in string format......


using System;
namespace inputdemo
{
class cls1
{
static void Main()
{
String str;
Console.WriteLine(" Enter Your Name");
str=Console.ReadLine();
Console.WriteLine("The Name Entered is "+str);

}
}
}

How we will get the input....

using System;
namespace name
{
class Hello
{
static void Main()
{
String str;
Console.WriteLine(" Enter Your Name");
str=Console.ReadLine(); //here we will get the input , it is in string type
Console.WriteLine("Your Name is "+str);
}
}
}

Hello World......

N.B : While doing the console you should be vigilent about the case...Because c# is case sensitive

using System;
namespace Hello
{
class world
{
static void Main()
{
Console.WriteLine("Hello World");
}
}
}

This is how console Application works,,,,

Console

Here it is explained how to use the console application


Note:-
Save the progarm with the extension .cs (if it is csharp)
eg:-program.cs

To compile the program go to the visual studio and take the visual studio command promt......
Change the control from the present folder to the folder where your program is stored

Suppose ur program is at D:\paul\vcs\program.cs

now to change your contorl use
c:\visuall\v8>d: <-(enter)
d:\>cd paul <-
d:\paul>cd vcs <-
D:\paul\vcs>csc progarm.cs


To run

D:\paul\vcs>program.exe <-

About Dot Net and How it works

As we Know The dot net supports many languages Let see how it works....


The .NET initiative offers a complete suite for developing and deploying applications. The suite consists of
.NET Products
.NET Services and
.NET Framework

The .NET Framework:-

It is the foundation on which you design, develop and deploy applications.

Its consistent and simplified programming model makes it easier to build robust applications.

The .NET Class Framework consists of a class library that works with any .NET language, such as Visual Basic and C#.
This class library is build in Object-oriented nature of the runtime

The .NET frame work base classes:-

The .NET framework base classes consists of Namespaces and Assemblies
Namespaces helps to create logical groups of related classes and interfaces.

An Assembly is a single deployable unit that contains all the information about the implementation of classes, Structures and Interfaces

COMMON LANGUAGE RUNTIME:-

Common Language Runtime provides functionality such as exception handling, security, debugging and versioning support to any language that targets it.
The CLR can execute programs written in any language.

HOW IT EXECUTE:-

When you compile a program developed in a language that targets the CLR, instead of compiling the source code into machine-level code, the compiler translates it into Microsoft Intermediate Language(MSIL) or Intermediate Language(IL). No matter which language has been used to develop the application it always gets translated into IL

The compiler created the .EXE or .DLL file.
When you execute the .EXE or .DLL file, the code and all the other relevant information from the base class library is sent to the class loader.

The Just In Time(JIT) compiler translates the code from IL into managed native code. The CLR supplies a JIT compiler for each supported CPU architecture.
During the process of compilation , the JIT compiler compiles only the code that is required during execution instead of compiling the complete IL code.

During JIT compilation the is also checked for type safety
After translating the IL into native code, the converted code is sent to the .NET runtime manager.

The .NET runtime manager executes the code. While executing the code, a security check is performed to ensure that the code has the appropriate permissions for accessing the available resources

Know About Object Oriented Programming

Object Oriented Programming(OOP's):-

Object Oriented Programming was first introduced by Dr. E F Codd in 1970’s.
OOP concept is related to concept of Classes and Objects.The main reason for introducing the oops is to provide data security.

Class :-

Class is a user defined Data Type
Class is just a Virtual concept of a collection of related items together which we cannot see or feel.

Object:-

Object is an Instance of a Class. We can access a Class only through its Objects.
A thing which has the properties of a class is known as Objects.
For eg:- Car is a Class and Benz is an Object of the class 'Car'
An Object have it's own identity
e.g:- From many Benz cars we identify it by its registration number

The main characteristics of Object Oriented Programming are:-

• Inheritance
• Encapsulation
• Abstraction
• Polymorphism

Inheritance:-

The ability of a class (Derived Class) to derive or Inherit the properties of another class (Base Class) is called Inheritance
eg:-A child inherits Many Property from his parents But it is not necessary to inherit all the properties....

Encapsulation:-

It is the process of wrapping of data and functions into a single unit

Process of Hiding the data from a user is called Encapsulation; also called Data Hiding.

Abstraction:-

The process of showing essential features without giving any explanations is known as Abstraction.
eg:- In case of a car a Person know only how to drive the car..its gear,break and all that only essintal for driving that car

Polymorphism:-

Poly means 'many
morphism means forms'
It is the process of existing in more than one form...

eg:- Behavior of a person in front of his authority and friends

Here c++ ,c# and java are object oriented programs

Before we start....

Variable :-

Variable is a named memory location
For a variable there will be memory address
value
e.g. :- inum,inum1,fnum,cname;



Rules For Declaring Variables :-

A Variable Should Start with an Alphabet
e.g. a, b,a1,name
Key Words are not allowed
e.g. int,float....etc
No special characters are allowed
e.g. @,#,! Etc... Exception is underscore(_)
Numbers are allowed ....
e.g. a12,b034 etc
Number should not be the Starting
e.g. 12a,13a these are wrong decleration



Data Types :-

Data type shows which type of values should a variable hold
There are mainly four types of basic data types
int - integer
float - floatting
double - double type value
char - character type value
e.g : - int a=10;
float c=15.5;
double aa=10.557857;
char ch=‘a’;
here a is a character not a variable so it is in single codes


Operator :-

Operators are used to do perform some operations on the variables

There are three types of operators
Arithmetic Operators
Relational ,,
Logical ,,


Arithmetic Operators :-

Arithmetic Operators are used to do mathematical operations
e.g . c=a+b;

The basic arithmetic Operators are

int a,b,c;
+ for addition e.g : c= a+b
- for subtraction e.g : c= a-b
* multiplication e.g : c=a*b;
/ division e.g : c=a/b; (5/2=2)
% modulo operator (returns remainder after division)
e.g : c=(a%b); (5%2=1)


Relational Operators:-


It shows the relation between the two variables
e.g : > (greater than)
< (less than)
>=(greater than or equal to)
<= (less than or equal to)
==(equals)
!=(not equal to)
e,g : (a>b),(a=b),(a!=b);


Logical Operators :

&& - Logical AND
e.g.(a>b&&a>c)
|| - Logical OR
e.g.(a>b||a==b)
! - Logical NOT
e.g(!a)