JavaScript
- Getting started with JavaScript
- Awesome Book
- Awesome Community
- Awesome Course
- Awesome Tutorial
- Awesome YouTube
- .postMessage() and MessageEvent
- AJAX
- Anti-patterns
- Arithmetic (Math)
- Arrays
- Arrow Functions
- Async functions (async/await)
- Async Iterators
- Automatic Semicolon Insertion - ASI
- Battery Status API
- Behavioral Design Patterns
- Binary Data
- Bitwise operators
- Bitwise Operators - Real World Examples (snippets)
- BOM (Browser Object Model)
- Built-in Constants
- Callbacks
- Classes
- Comments
- Comparison Operations
- Conditions
- Console
- Constructor functions
- Context (this)
- Cookies
- Creational Design Patterns
- Custom Elements
- Data attributes
- Data Manipulation
- Datatypes in Javascript
- Date
- Date Comparison
- Debugging
- Declarations and Assignments
- Destructuring assignment
- Detecting browser
- Enumerations
- Error Handling
- Escape Sequences
- Evaluating JavaScript
- Events
- execCommand and contenteditable
- Fetch
- File API, Blobs and FileReaders
- Fluent API
- Functional JavaScript
- Functions
- Generators
- Geolocation
- Global error handling in browsers
- History
- How to make iterator usable inside async callback function
- IndexedDB
- Inheritance
- Intervals and Timeouts
- JavaScript Variables
- JSON
- Linters - Ensuring code quality
- Localization
- Loops
- Map
- Memory efficiency
- Method Chaining
- Modals - Prompts
- Modularization Techniques
- Modules
- Namespacing
- Navigator Object
- Notifications API
- Objects
- Accesor properties (get and set)
- Arrays are Objects
- Convert object's values to array
- Creating an Iterable object
- Descriptors and Named Properties
- Dynamic / variable property names
- Iterating over Object entries - Object.entries()
- Lock property description
- Non enumerable property
- Object cloning
- Object properties iteration
- Object rest/spread (...)
- Object.assign
- Object.defineProperty
- Object.freeze
- Object.getOwnPropertyDescriptor
- Object.keys
- Object.seal
- Object.values()
- Properties with special characters or reserved words
- Read-Only property
- Retrieving properties from an object
- Shallow cloning
- Performance Tips
- Promises
- Prototypes, objects
- Proxy
- Regular expressions
- requestAnimationFrame
- Reserved Keywords
- Same Origin Policy & Cross-Origin Communication
- Scope
- Screen
- Security issues
- Selection API
- Server-sent events
- Set
- Setters and Getters
- Strict mode
- Strings
- Symbols
- Tail Call Optimization
- Template Literals
- The Event Loop
- Tilde ~
- Timestamps
- Transpiling
- Unary Operators
- Unit Testing Javascript
- Using javascript to get/set CSS custom variables
- Variable coercion/conversion
- Vibration API
- WeakMap
- WeakSet
- Web Cryptography API
- Web Storage
- WebSockets
- Workers
JavaScript Objects Read-Only property
Example
5
Using property descriptors we can make a property read only, and any attempt to change it's value will fail silently, the value will not be changed and no error will be thrown.
The writable property in a property descriptor indicates whether that property can be changed or not.
var a = { };
Object.defineProperty(a, 'foo', { value: 'original', writable: false });
a.foo = 'new';
console.log(a.foo);
Console output
original
