Introduction to JavaScript if-else Statements

In JavaScript, if-else statements allow you to control the flow of your code based on specific conditions. These statements enable you to execute different blocks of code depending on whether a condition is true or false. In this article, we will introduce if-else statements in JavaScript and provide examples to illustrate their usage.

Syntax of if-else Statement

The basic syntax of an if-else statement in JavaScript is as follows:

    
      if (condition) {
        // Code to be executed if the condition is true
      } else {
        // Code to be executed if the condition is false
      }
    
  

Example:

Consider the following example that checks if a given number is positive or negative:

    
      var number = -5;

      if (number > 0) {
        console.log("The number is positive");
      } else {
        console.log("The number is negative");
      }
    
  

JavaScript if-else if-else Statements

In JavaScript, if-else if-else statements provide a way to test multiple conditions and execute different blocks of code accordingly. These statements allow you to handle various scenarios and make decisions based on specific conditions. In this article, we will explore the usage of if-else if-else statements in JavaScript with examples.

Syntax of if-else if-else Statement

The syntax of an if-else if-else statement in JavaScript is as follows:

    
      if (condition1) {
        // Code to be executed if condition1 is true
      } else if (condition2) {
        // Code to be executed if condition2 is true
      } else {
        // Code to be executed if all conditions are false
      }
    
  

Example:

Consider the following example that determines the grade based on a student's score:

    
      var score = 85;
      var grade;

      if (score >= 90) {
        grade = "A";
      } else if (score >= 80) {
        grade = "B";
      } else if (score >= 70) {
        grade = "C";
      } else {
        grade = "D";
      }

      console.log("Grade: " + grade);
    
  

JavaScript Ternary Operator

In JavaScript, the ternary operator provides a concise way to write if-else statements with a single expression. It is a shorthand notation for conditionally assigning values or executing code based on a condition. In this article, we will explore the usage of the ternary operator in JavaScript with examples.

Syntax of Ternary Operator

The syntax of the ternary operator in JavaScript is as follows:

    
      condition ? expression1 : expression2
    
  

Example:

Consider the following example that determines if a number is positive or negative using the ternary operator:

    
      var number = -5;
      var message = (number > 0) ? "The number is positive" : "The number is negative";
      console.log(message);