ES6 Array map()
🔁 ES6 map() Method
The map() method creates a new array by applying a function to each item of an existing array.
✔ Does not modify the original array
✔ Returns a new array
🧠 Basic Syntax
| Parameter | Meaning |
|---|---|
value |
Current element |
index |
Current position |
array |
Full array (optional) |
🔍 Example: Basic map()
🎯 Example: Using map() with Strings
🧩 map() in React (Very Important)
React commonly uses map() to render lists dynamically.
Example:
✔ Each element needs a unique key prop in React when rendering lists.
🏷️ Using map() with Objects
Rendering in React:
🔧 map() + Arrow Function + JSX Example
📌 Common Mistakes
❌ Missing key:
✔ Correct way:
🎉 Summary
| Feature | Value |
|---|---|
| Creates new array | ✔ |
| Useful in React | ✔ |
| Does not modify original array | ✔ |
| Common for rendering lists | ✔ |
