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JavaScript Optional Chaining with Array Index

 1 year ago
source link: https://masteringjs.io/tutorials/fundamentals/optional-chaining-array
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JavaScript Optional Chaining with Array Index

Feb 15, 2023

JavaScript optional chaining works with array indexes. Just add the ?. before your square brackets []. Looks weird, but it works!

const characters = [
  { name: 'Jean-Luc Picard', age: 59 },
  { name: 'Will Riker', age: 29 }
];

// `?.[2]` is how you access the 2nd element with optional chaining
characters?.[2]?.age; // undefined
characters?.[1].age; // 29

characters[1]?.doesnt?.exist; // undefined

You can't use ?. with a number, that causes a syntax error. But you can also use ?.[] with variables as follows.

const index = 1;

characters?.[index].age; // 29

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