Why error handling is required in Javascript - See It in Action

Why error handling is required

📖 Scenario: Imagine you are building a simple calculator app that divides two numbers. Sometimes users might enter zero as the divisor, which causes an error. You want to handle this error gracefully so the app does not crash and shows a friendly message instead.

🎯 Goal: Learn why error handling is important by creating a small program that divides two numbers and handles division by zero errors.

📋 What You'll Learn

Create two variables called numerator and denominator with exact values 10 and 0

Create a variable called result to store the division result

Use a try block to perform the division numerator / denominator

Use a catch block to catch any errors and set result to the string 'Error: Cannot divide by zero'

Print the value of result

💡 Why This Matters

🌍 Real World

In real apps, users can enter wrong data or unexpected things can happen. Error handling keeps apps running smoothly and helps users understand problems.

💼 Career

Knowing how to handle errors is important for all programmers to build reliable and user-friendly software.

1

DATA SETUP: Create numerator and denominator variables

Create two variables called numerator and denominator with values 10 and 0 respectively.

Javascript

# Create variables numerator and denominator with values 10 and 0
// Your code here

Need a hint?

Use const numerator = 10; and const denominator = 0;

2

CONFIGURATION: Create a result variable

Create a variable called result and set it to null.

Javascript

const numerator = 10;
const denominator = 0;
// Create a variable result and set it to null
// Your code here

Need a hint?

Use let result = null; to create the variable.

3

CORE LOGIC: Use try-catch to handle division by zero

Use a try block to divide numerator by denominator and assign it to result. Use a catch block to set result to the string 'Error: Cannot divide by zero' if an error occurs.

Javascript

const numerator = 10;
const denominator = 0;
let result = null;
// Use try-catch to divide numerator by denominator
// Your code here

Need a hint?

Check if denominator is zero inside try, throw an error, and catch it to set result.

4

OUTPUT: Print the result

Write console.log(result) to display the value of result.

Javascript

const numerator = 10;
const denominator = 0;
let result = null;
try {
    if (denominator === 0) {
        throw new Error('Cannot divide by zero');
    }
    result = numerator / denominator;
} catch (error) {
    result = 'Error: Cannot divide by zero';
}
// Print the result
// Your code here

Need a hint?

Use console.log(result); to show the output.