How can I use closures in JavaScript to create private variables within a function?
Asked on Oct 06, 2025
Answer
Closures in JavaScript allow you to create private variables by enclosing them within a function scope, making them inaccessible from outside that function. Here's a simple example demonstrating this concept.
<!-- BEGIN COPY / PASTE -->
function createCounter() {
let count = 0; // Private variable
return {
increment: function() {
count++;
return count;
},
decrement: function() {
count--;
return count;
},
getCount: function() {
return count;
}
};
}
const counter = createCounter();
console.log(counter.increment()); // 1
console.log(counter.increment()); // 2
console.log(counter.decrement()); // 1
console.log(counter.getCount()); // 1
<!-- END COPY / PASTE -->Additional Comment:
✅ Answered with JavaScript best practices.- The "createCounter" function defines a private variable "count" that is not accessible directly from outside.
- The returned object contains methods that form closures over the "count" variable, allowing controlled access and modification.
- This pattern is useful for encapsulating data and restricting direct access, promoting data integrity.
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