How do I retrieve array elements by their indices in JavaScript?

Retrieving Array Elements at Specific Indices in JavaScript: A Comprehensive Guide

Question:

How can we obtain the value stored at a particular index within an array in JavaScript? We have an array with a value at index 1 but require a method to retrieve it effortlessly.

Answer:

Accessing array elements by index is a fundamental operation in JavaScript. There are two primary methods for doing so:

1. Bracket Notation:

The bracket notation provides a straightforward way to access array elements. It involves specifying the target index within square brackets appended to the array name. For instance:

<code class="javascript">var myValues = new Array();
var valueAtIndex1 = myValues[1];</code>

2. .at() Method:

Available in modern browsers and JavaScript engines, the .at() method offers a more flexible approach. It can both access elements from the start and end of the array using positive and negative indices, respectively. Here's an example:

<code class="javascript">var valueAtIndex1 = myValues.at(1);</code>

On positive indices, both methods behave identically. Bracket notation is more commonly used, while .at() allows for accessing elements from the end using negative indices (-1 refers to the last element, -2 to the second last element, and so on).

Additional Notes:

• The index of the first element in an array is 0.
• When using negative indices with the .at() method, indices below -array.length will overflow and provide values from the positive end of the array.

For further details and examples, refer to the MDN documentation on [Array.prototype.at()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/at).

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