JavaScript的关于数组的10种简化方法，必须掌握！

JS JavaScript filter forEach includes

1. filter()

   const words = ['HTML', 'CSS', 'JavaScript', 'Python', 'Java'];

   const longWords = words.filter(word => word.length > 4);

   console.log(longWords); // ["JavaScript", "Python"]

2. forEach()

   const words = ['HTML', 'CSS', 'JavaScript'];

   words.forEach(word => console.log(word));

   // HTML // CSS // JavaScript

3. some()

   const myArray = [1, 2, 3, 4, 5];

   const evenExists = myArray.some(element => element % 2 === 0);

   console.log(evenExists); // true

4. every()

   const myArray = [1, 2, 3, 4, 5];

   const allEven = myArray.every(element => element % 2 === 0);

   console.log(allEven); // false

5. includes()

   const numbers = [1, 2, 3, 4, 5];

   console.log(numbers.includes(2)); // true

   console.log(numbers.includes(8)); // false

6. map()

   const numbers = [1, 2, 3, 4, 5];

   const doubled = numbers.map(x => x * 2);

   console.log(doubled);

7. reduce()

   const numbers = [10, 20, 30, 40];

   const sum = numbers.reduce((x, y) => x + y, 0);

   console.log(sum); // 100

8. sort()

   const techs = ['HTML', 'CSS', 'JavaScript']; techs.sort(); console.log(techs); // ["CSS", "HTML", "JavaScript"]

   const numbers = [1, 30, 4, 21, 100000]; numbers.sort((x, y) => x - y); console.log(numbers); // [1, 4, 21, 30, 100000]

9. find()

   const numbers = [7, 14, 8, 128, 56];

   const found = numbers.find(element => element > 10);

   console.log(found); // 14

10. findIndex()

    const numbers = [5, 12, 8, 130, 44];

    const indexFound = numbers.findIndex(element => element > 15);

    console.log(indexFound); // 3

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