February 2018
Intermediate to advanced
298 pages
8h 22m
English
Content preview from Learn ECMAScript - Second Edition
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The findIndex(testingFunc) method
The findIndex() method is similar to the find() method. The findIndex() method returns the index of the satisfied array element instead of the element itself. Take a look at this example:
const x = 12;const arr = [11, 12, 13];const result = arr.findIndex( (value, index, array) => value == x );console.log(result);
The output is 1.
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