What are the Different Ways to Loop Through a JavaScript Array?

Looping Through an Array Using JavaScript

Iterating through the elements of an array is a common task in JavaScript. There are several approaches available, each with its own strengths and limitations. Let's explore these options:

Arrays

1. for-of Loop (ES2015 )

This loop iterates over the values of an array using an iterator:

const arr = ["a", "b", "c"];
for (const element of arr) {
  console.log(element); // "a", "b", "c"
}

2. forEach

forEach is a method that iterates over the array and calls a function for each element:

arr.forEach(element => {
  console.log(element); // "a", "b", "c"
});

3. Simple for Loop

This loop uses a counter variable to iterate over the array elements:

for (let i = 0; i < arr.length; i++) {
  console.log(arr[i]); // "a", "b", "c"
}

4. for-in Loop (with Safeguards)

for-in iterates over an array's properties, which include its elements. However, it's important to use safeguards to avoid iterating over prototype properties:

for (const property in arr) {
  // Check if 'property' is an array element property
  if (arr.hasOwnProperty(property)) {
    console.log(arr[property]); // "a", "b", "c"
  }
}

5. Iterator (ES2015 )

Arrays are iterable objects and provide an iterator that can be manually advanced using next():

const iterator = arr[Symbol.iterator]();
while (true) {
  const result = iterator.next();
  if (result.done) break;
  console.log(result.value); // "a", "b", "c"
}

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