Tag Archives: assignment

Arithmetic and assignment operators in C#

Operators

Operators are symbols that are used to perform operations on data. The range of different operations you can perform can usually be placed in these four categories:

  • Arithmetic operators
  • Assignment operators
  • Equality operators
  • Logical operators

In this tutorial we will look at arithmetic and assignment operators used in the C# language. Later on in these tutorials we will also look at equality and logical operators when we work with conditional statements.

Arithmetic operators

Arithmetic operators are used for performing standard math operations on variables and are usually only used on number variables eg. int and float (although they can be used for other things too eg. the  + operator can be used to join two strings together).

Operator Name / description
+ Addition – this operator is used to add two numbers together. It can also be used to concatenate (join) two strings together.
Subtraction – this operator is used to subtract one number from another.
* Multiplication – this operator is used to multiply two numbers together.
/ Division – this operator is used to divide one number by another.
% Modulus – this operator is used to divide one number by another but instead of returning the result, it returns the remainder of the division. Eg. 5%2 would return a result of 1.

Brackets can also be used for more complex math operations eg. 5 + (10 * (6 / 3) / 2);

The assignment operators follow standard mathematic order of operations. That means that the math works from left to right. Parenthesis are done first, multiplication and division comes second, and then addition and subtraction come third.

Assignment operators

Assignment operators are used to assign a value to a variable. The most frequently used assignment operator is the equals (=) sign. There are other operators as well that are used to combine multiple operations into one. The syntax of a standard variable assignment looks like this:

<variable name> <assignment operator> <value>;

For example: x = 5; (or int x = 5; if the variable’s type has not already been declared).

The table below shows the different assignment operators available in C#.

Operator Description
= The equals sign is used to assign the value on the right side of the equals sign to the variable on the left side of the equals sign.
+= , -= , *= and /= These assignment operators are also used to perform arithmetic operations and assign the result to the variable eg. x *= 5 is the same as saying x = x * 5.
++ and — These assignment operators are called increment and decrement operators and are used to increase or decrease the value of a variable by 5. For example, x++ is the same as saying x = x + 1.

Watch the video below to see how arithmetic and assignment operators are used in the C# language and then scroll down for the sample code.

Sample code

using System;

namespace MyCSharpProject
{
  class MainClass
  {
    public static void Main(string[] args)
    {
      string message = "The result is ";
      float num1 = 6f;
      float num2 = 4f;

      float result = num1 + num2 + 10f;

      result = num1 - num2;
      result = num1 * num2;
      result = num1 / num2;
      result = num1 % num2;

      int num3 = 30;
      num3--;

      Console.WriteLine(result);
      Console.WriteLine(num3);
    }
  }
}

Next tutorial: Comments

Operators in C#

Operators

Operators are symbols that are used to perform operations on data. The range of different operations you can perform can usually be placed in these four categories:

  • Arithmetic operators
  • Assignment operators
  • Equality operators
  • Logical operators

You will see how these operators can be used for conditional statements in the next tutorial but for now, you can watch the video below to learn about the different types of operators in the C# programming language.

Arithmetic operators

Arithmetic operators are used for performing standard math operations on variables and are usually only used number variables (although they can be used for other things too).

Operator Name / description
+ Addition – this operator is used to add two numbers together. It can also be used to concatenate (join) two strings together.
Subtraction – this operator is used to subtract one number from another.
* Multiplication – this operator is used to multiply two numbers together.
/ Division – this operator is used to divide one number by another.
% Modulus – this operator is used to divide one number by another but instead of returning the result, it returns the remainder of the division. Eg. 5%2 would return a result of 1.

Brackets can also be used for more complex math operations eg. 5 + (10 * (6 / 3) / 2);

The assignment operators follow standard mathematic order of operations. That means that the math works from left to right. Parenthesis are done first, multiplication and division comes second, and then addition and subtraction come third.

Assignment operators

Assignment operators are used to assign a value to a variable. The most frequently used assignment operator is the equals (=) sign. There are other operators as well that are used to combine multiple operations into one. The syntax of a standard variable assignment looks like this:

<variable name> <assignment operator> <value>;

For example: x = 5;

The table below shows the different assignment operators available in C#.

Operator Description
= The equals sign is used to assign the value on the right side of the equals sign to the variable on the left side of the equals sign.
+= , -= , *= and /= These assignment operators are also used to perform arithmetic operations and assign the result to the variable eg. x *= 5 is the same as saying x = x * 5.
++ and – These assignment operators are called increment and decrement operators and are used to increase or decrease the value of a variable by 5. For example, x++ is the same as saying x = x + 1.

Equality operators

Equality operators are used to compare two values. The result of using an equality operator can either be true or false. The only type of variable that can store the result of an equality operator is a Boolean. The table below describes the equality operators used in C#.

Operator Description
== This operator is used to check if two values are equal eg. x == 5 would return true if x had a value of 5.
> and < The ‘greater than’ and ‘less than’ operators are used to check if values are greater than or less than another value. For example, x > 5 (if the value of x was 3 than it would return false).
>= and <= The ‘greater than or equal to’ and ‘less than or equal to’ operators are similar to the ‘greater than’ and ‘less than’ operators. For examples, 5>=5 would return true because 5 is equal to 5, and 6<=10 would return true because 6 is less than 10.
!= The ‘not equal’ operator is used to check if two values are not the same as each other. For example, x != 10 would return true if the value of x was 9 because 9 is not equal to 10. However, y != 5 would return false if the value of y was 5.

Logical operators

Logical operators are used for complex conditions. The table below describes each logical operator.

Operator Description
&& This is known as the AND operator and is used to check if both values are true in a complex condition.
|| The is known as the OR operator and is used to check if at least one of the values is true when two values are compared. It will return true if either one or both values are true.
! This is known as the NOT operator and will return the opposite of a Boolean value. For example !true; would return false and !false; would return true.

 

Operators

If you have created your own variables and assigned them each a value (such as a string or integer), then you will already be familiar with the assignment operator which is a single = (equals sign).

There are other operators used for calculations though such as adding, subtracting, multiplying, dividing, increasing and decreasing values, etc. Take a look at the source code to see what is available.

Make sure you also watch the video about operators here.

<!DOCTYPE html>
<html lang="en"
<head>
 <meta charset="utf-8"/>
 <title>JavaScript - Operators</title>
 <script type="text/javascript">
 var x = 5, y = 10; //variables can be initialised on one line, separated by commas
 var z = x + y; // this is how variables can be added
 
 z++ //this increases the z variable value by 1
 
 z-- //this decreases the z variable value by 1
 
 // operators include + (plus) - (minus) * (multiply) / (divide) and % (modulus) which returns the remainder from division
 
 x+=y; //this is an example of compound addition. It is the equivalent of x = x + y
 // variables can be added using the compound addition += , compound subtraction -= , compound multiplication *= or compound addition /=
 
 document.write(z); // now let's see what the z variable displays after these modifications.
 
 </script>
 
</head>
<body>
 
 
</body>
</html>