JS数组方法

[1, 2, 3].length // 3
[1, 2, 3].push(4) // [1,2,3,4]
[1, 2, 3].unshift(0) // [0,1,2,3]
[1, 2, 3].pop() // [1,2]
[1, 2, 3].shift() // [2,3]
[1, 2, 3].at(2) // 3
[1, 2, 3].indexOf(3) // 2
[1, 2, 3].includes(2) // true
[1, 2, 3].map((num) => Math.pow(num, 2));//[1,4,9]
[1, 2, 3].filter((num) => num % 2);//[1,3]
[1, 2, 3].every((num) => num > 1);//false
[1, 2, 3].some((num) => num == 3);//true
[1, 2, 3].fill(10);//[10,10,10]
[1, 2, 3].reduce((acc, num) => acc + num, 0);//6
[1, 2, 3].concat([4, 5]);//[1,2,3,4,5]
[1, 2, 3].reverse();//7 [3,2,1]
[2, 1, 3].sort();//[1,2,3]
[1, 2, 3].join('-');//7 1-2-3
[1, 2, [3]].flat();//[1,2,3]
[1, 2, 3].find((num, i) => i === 1);//2
[1, 2, 3].findIndex((num) => num === 2);//1
[1, 2, 3].toString();//1,2,3
[1, 2, 3].slice(1, 3);//[2,3]
[1, 4].splice(1, 0, 2, 3);//[1,2,3,4]
Array.isArray("[l,2,3]"); //false
Array.from("123");//['1'，'2'，'3']