Conditional Statements in JavaScript

What are Conditional Statements in JavaScript ?

Conditional statements in JavaScript allow you to execute specific blocks of code based on conditions. If the condition meets then a particular block of action will be executed otherwise it will execute another block of action that satisfies that particular condition.

There are several methods that can be used to perform Conditional Statements in JavaScript.

• if Statement
• if-else Statement
• else if Statement
• switch Statement
• Ternary Operator

We will explore all the above methods along with their basic implementation with the help of examples.

JavaScript if Statement

The if statement is used to evaluate a particular condition. If the condition holds true, the associated code block is executed.

Syntax:

if ( condition ) {
    // If the condition is met, 
    //code  will get executed.
}

Example: In this example, we are using the if statement to find given number is even or odd.

Given number is even number.

JavaScript if-else Statement

The if-else statement will perform some action for a specific condition. Here we are using the else statement in which the else statement is written after the if statement and it has no condition in their code block.

Syntax:

if (condition1) {
    // Executes when condition1 is true
    if (condition2) {
        // Executes when condition2 is true
    }
}

Example: In this example, we are using the above-explained approach.

you are eligible of driving licence

JavaScript else if Statement

The else if statement in JavaScript allows handling multiple possible conditions and outputs, evaluating more than two options based on whether the conditions are true or false.

Syntax:

if (1st condition) {
    // Code for 1st condition
} else if (2nd condition) {
    // ode for 2nd condition
} else if (3rd condition) {
    // Code for 3rd condition
} else {
    //  ode that will execute if all 
    // above conditions are false
}

Example: In this example, we are using the above-explained approach.

Given number is zero.

JavaScript Switch Statement (JavaScript Switch Case)

As the number of conditions increases, you can use multiple else-if statements in JavaScript. but when we dealing with many conditions, the switch statement may be a more preferred option.

Syntax:

switch (expression) {
    case value1:
        statement1;
        break;
    case value2:
        statement2;
        break;
    . . .
    case valueN:
        statementN;
        break;
    default:
        statementDefault;
};

Example: In this example, we find a branch name Based on the student’s marks, this switch statement assigns a specific engineering branch to the variable Branch. The output displays the student’s branch name,

Student Branch name is : Mechanical engineering

JavaScript Ternary Operator ( ?: )

The conditional operator, also referred to as the ternary operator (?:), is a shortcut for expressing conditional statements in JavaScript.

Syntax:

condition ? value if true : value if false

Example: In this example, we use the ternary operator to check if the user’s age is 18 or older. It prints eligibility for voting based on the condition.

You are eligible to vote.