JavaScript Examples

Generated by AI, corrected by PeatSoft

Hello World (Console)

console.log("Hello, World!");

This code prints "Hello, World!" to the console.

Hello World (Browser)

<!DOCTYPE html>
<html lang="en">
<head>
</head>
<body>
    <h1 id="message"></h1>
    <script>
        // This code will run when the page is loaded
        document.getElementById("message").innerHTML = "Hello, World!";
    </script>
</body>
</html>

This code prints "Hello, World!" in the browser.

Variables

let name = "Alice";
const age = 30;
console.log(name + " is " + age + " years old.");

This creates a variable `name` and a constant `age`, then logs a string to the console.

Functions

function add(a, b) {
    return a + b;
}

let sum = add(5, 3);
console.log("The sum is: " + sum);

This defines a function `add` that takes two parameters and returns their sum.

Conditional Statements

let score = 85;

if (score >= 90) {
    console.log("Grade: A");
} else if (score >= 80) {
    console.log("Grade: B");
} else {
    console.log("Grade: C");
}

This code checks the `score` and logs the corresponding grade.

Loops

for (let i = 0; i < 5; i++) {
    console.log("Iteration number: " + i);
}

This loop iterates five times, printing the iteration number to the console.

Arrays

let fruits = ["apple", "banana", "cherry"];

fruits.forEach(function(fruit) {
    console.log(fruit);
});

This code initializes an array of fruits and uses `forEach` to print each fruit.

Objects

let person = {
    name: "Bob",
    age: 25,
    greet: function() {
        console.log("Hello, my name is " + this.name);
    }
};

person.greet();

This initializes an object `person` with properties and a method, then calls the `greet` method.

Promises

let fetchData = new Promise((resolve, reject) => {
    let success = true;

    if (success) {
        resolve("Data fetched successfully!");
    } else {
        reject("Error fetching data.");
    }
});

fetchData
    .then(response => console.log(response))
    .catch(error => console.log(error));

This creates a simple promise that resolves or rejects based on a condition.

Asynchronous Functions

async function fetchData() {
    return "Data fetched!";
}

fetchData().then(response => console.log(response));

This defines an asynchronous function that returns a string and uses `.then()` to log the result.