const inventory = [
    {name: 'apples', quantity: 2},
    {name: 'bananas', quantity: 0},
    {name: 'cherries', quantity: 5}
];
const result = inventory.find( fruit => fruit.name === 'cherries' );

console.log(result) // { name: 'cherries', quantity: 5 }

const inventory = [
    {name: 'apples', quantity: 2},
    {name: 'bananas', quantity: 0},
    {name: 'cherries', quantity: 5}
];
const result = inventory.findIndex( fruit => fruit.name === 'cherries' );
console.log(result); //打印数据为2

let arr = [99, 520, 1314];
let result = arr.map(item => {
    console.log(item)
});
// 99 520 1314
for (item of arr) {
    console.log(item)
}
// 99 520 1314

let arr = [1, 11, 111, 1111];
let result = arr.reduce((tmp, item, index) => {
    console.log(tmp, item, index);
    // 1 11 1
    // 12 111 2
    // 123 1111 3
    return tmp + item;
});
console.log(result);//可以用来求和？
// 1234

let arr = [
    { name: '临枫', bodyPrice: -50000 },
    { name: '怡晨', bodyPrice: 1000000000 },
    { name: '文涛', bodyPrice: 250 },
    { name: '姜总', bodyPrice: 999999999 },
    { name: '闫经理', bodyPrice: 99999},
    { name: '陈队长', bodyPrice: 1},
];
// 过滤身价大于一亿的
let result = arr.filter(p => p.bodyPrice >= 100000000);
console.log(result)
// [{name: "怡晨", bodyPrice: 1000000000},
// {name: "姜总", bodyPrice: 999999999}]

let arr = [9, 8, 7, 6];
arr.forEach((item, index) => {
    console.log(index, ">>>", item);
});
// 0 ">>>" 9
// 1 ">>>" 8
// 2 ">>>" 7
// 3 ">>>" 6
// 无下标的
arr.forEach(item => {
    console.log(item);
});
//9 8 7 6

const arr1 = [1, 2, 3];
const arr2 = [4, 5, 6];
console.log({ ...arr1, ...arr2 }); //输出[1,2,3,4,5,6]
console.log([...arr1, ...arr2]); //输出[1,2,3,4,5,6]
console.log(...arr1); //输出1 2 3
var p = { ...arr1, ...arr2 };
console.log(p);//{0: 4, 1: 5, 2: 6}
console.log(p[1])//5

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