C# Variables with Examples

In C#, Variables will represent storage locations and each variable has a particular type that determines what type of values can be stored in the variable.

 

C# is a Strongly Typed programming language so before we perform any operation on variables, it’s mandatory to define a variable with the required data type to indicate what type of data that variable can hold in our application.

Syntax of C# Variables Declaration

Following is the syntax of declaring and initializing variables in c# programming language.

 

[Data Type] [Variable Name];

[Data Type] [Variable Name] = [Value];

[Access Specifier] [Data Type] [Variable Name] = [Value];

If you observe the above syntax, we added a required data type before the variable name to tell the compiler about what type of data the variable can hold or which data type the variable belongs to.

 

[Data Type] - It’s a type of data the variable can hold such as integer, string, decimal, etc.

 

[Variable Name] - It’s a name of the variable to hold the values in our application.

 

[Value] - Assigning a required value to the variable.

 

[Access Specifier] - It is used to define access permissions for the variable.

 

Now we will see how to define variables in our c# applications with examples.

C# Variables Declaration Example

Following is the example of using the variables in c# programming language.

 

using System;

 

namespace Tutlane

{

    class Program

    {

        static void Main(string[] args)

        {

            int number = 10;

            string name = "Suresh Dasari";

            double percentage = 10.23;

            char gender = 'M';

            bool isVerified = true;

            Console.WriteLine("Id: " + number);

            Console.WriteLine("Name: " + name);

            Console.WriteLine("Percentage: " + percentage);

            Console.WriteLine("Gender: " + gender);

            Console.WriteLine("Verified: " + isVerified);

            Console.ReadLine();

        }

    }

}

If you observe the above c# variables example, we defined multiple variables with different data types and assigned values based on our requirements.

Output of C# Variables Declaration Example

When you execute the above program by pressing Ctrl + F5 or click on Start option in the menu bar you will get the result like as shown below.

 

C# Variables Declaration Example Result

 

If you observe the above result, we are able to print the variables in our c# application based on our requirements.

Rules to Declare C# Variables

Before we declare and define variables in c# programming language, we need to follow particular rules.

 

  • You can define a variable name with the combination of alphabets, numbers, and underscore.
  • A variable name must always start with either alphabet or underscore but not with numbers.
  • While defining the variable, no white space is allowed within the variable name.
  • You should not use any reserved keywords such as int, float, char, etc. for a variable name.
  • In c#, once the variable is declared with a particular data type, it cannot be re-declared with a new type and we shouldn’t assign a value that is not compatible with the declared type.

The following are some valid ways to define the variable names in the c# programming language.

 

int abc;

float a2b;

char _abc;

The following are some of the Invalid ways of defining the variable names in c# programming language.

 

int a b c;

float 2abc;

char &abc;

double int;

C# Multiple and Multi-Line Variables Declaration

In c#, we can declare and initialize multiple variables of the same data type in a single line by separating with a comma.

 

Following is the example of defining the multiple variables of the same data type in a single line by separating with a comma in c# programming language.

 

int a, b, c;

float x, y, z = 10.5;

While declaring the multiple variables of the same data type, we can arrange them in multiple lines to make it more readable and the compiler will treat it a single statement until it encounters a semicolon (;).

 

Following is the simple of defining the multiple variables of the same data type in multiple lines in c# programming language.

 

int a,

     b,

     c;

float x,y,

       z = 10.5;

C# Variables Assignment

In c#, once we declare and assign a value to the variable that can be assigned to another variable of the same data type.

 

Following is the example of assigning a value of one variable to another variable of the same type in c# programming language.

 

int a = 123;

int b = a;

string name = "suresh";

string firstname = name;

In c#, it’s mandatory to assign a value to the variable before we use it otherwise we will get a compile-time error.

 

In case, if we try to assign a value of string data type to an integer data type or vice versa like as shown below, we will get an error like “cannot implicitly convert type int to string”.

 

int a = 123;

string name = a;

This is how we can use variables in c# programming language based on our requirements. 

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