Objects & Dictionaries
Work with key-value pairs and complex data structures. Learn object literals, properties, methods, destructuring, spread operator, and JSON. Organize related data into meaningful structures.
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What You'll Learn
Object literals and property access
Adding, updating, and deleting properties
Object methods and this keyword
Destructuring assignment
Spread and rest operators
JSON parsing and stringification
Frequently Asked Questions
What is the difference between dot notation and bracket notation?
Dot notation (obj.property) is cleaner but only works with valid identifiers. Bracket notation (obj["property"]) works with any string, variables, or property names with special characters.
How do I copy an object without modifying the original?
Use the spread operator {...obj} for shallow copies or structuredClone() for deep copies. Shallow copies only copy the first level; nested objects still reference the original.
What is JSON and why is it important?
JSON (JavaScript Object Notation) is a text format for data exchange. It's used for APIs, configuration files, and data storage. JSON.stringify() converts objects to JSON strings, and JSON.parse() converts JSON strings to objects.
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