The findIndex() method returns the index of the first array element that passes a test function.
This example finds the index of the first element that is larger than 18:
Example
const numbers = [4, 9, 16, 25, 29];
let first = numbers.findIndex(myFunction);
function myFunction(value, index, array) {
return value > 18;
}
let first = numbers.findIndex(myFunction);
function myFunction(value, index, array) {
return value > 18;
}
Note that the function takes 3 arguments:
- The item value
- The item index
- The array itself
Array.findIndex() is not supported in older browsers. The first browser versions with full support is listed below.
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