Properties, methods and this.
✍️ 3 exercises + code challenge in this lessonAn object groups related data and behaviour as key: value pairs.
person.name or brackets person["name"].person.age = 30;delete person.age;this refers to the object.Object.keys(), Object.values() and Object.entries() list an object's contents.
Mastering JavaScript Objects helps you write clean and reliable JavaScript code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
<pre id="out"></pre>
<script>
const log = (...a) => document.getElementById("out").textContent += a.join(" ") + "\n";
const person = {
firstName: "Ayesha",
lastName: "Malik",
age: 26,
fullName() {
return this.firstName + " " + this.lastName;
}
};
person.city = "Islamabad";
log(person.fullName(), "is", person["age"]);
log("Keys:", Object.keys(person).join(", "));
for (const [key, value] of Object.entries(person)) {
if (typeof value !== "function") log(" -", key, "=", value);
}
</script>Check what you learned in “JavaScript Objects”.
Read the name property.
const user = { name: "Ali" };
log(user]);
Inside an object method, what does "this" refer to?
Create an object car with brand "Toyota" and year 2020, then log car.brand.
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