Med Java

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====== Java Script Find / Find Index methods ======

Unlike [[java-script:filter-method|filter method]] that returns all the matching elements, **find and findIndex** will **stop at the first matching element found**.

===== Find =====

The **find** method returns the first element in an array that satisfies a given test function. If no elements satisfy the test, it returns **undefined**.

<code javascript>
const numbers = [10, 20, 30, 40];
const found = numbers.find(number => number > 20);
console.log(found); // 30
</code>

===== Find index =====

The **findIndex** method returns the index of the first element in an array that satisfies a given test function. If no elements satisfy the test, it returns **-1**.

<code javascript>
const numbers = [10, 20, 30, 40];
const index = numbers.findIndex(number => number > 20);
console.log(index); // 2
</code>

===== Summary =====

<note>
  * Use **find** when you want to retrieve the **first item** that satisfies a condition.
  * Use **findIndex** when you need the **index of the first item** that satisfies a condition.
  * Use **[[java-script:filter-method|filter]]** when you need **all items** that satisfy a condition.
</note>