关于在掘金学到的东西记录
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关于多个promise发送请求,如果需要很多请求,可以使用async,因为多个Promise会造成回调地狱等情况
const fun =async()=>{
const res1 = await fn1()
const res2 = await fn2()
}
如果我们要获得对象里面所有的属性,除了for循环也可以用Object.values()
const abc = {"小明":18,"小红":20,"小蓝":22,"小刚":33}
console.log(Object.values(abc)) //18,20,22,33
const abc = {"小明":18,"小红":20,"小蓝":22,"小刚":33} console.log(Object.values(abc)) //18,20,22,33
如果碰到了多维数组,如何把多维数组里面的东西获取到然后返回一个新数组,这就需要数组自身携带的flat()方法
var obj = [1, [2, [3, [4, 5]]]];
console.log(obj.flat(Infinity)); // ['a', 'b', 'c']
var obj = [1, [2, [3, [4, 5]]]];
console.log(obj.flat(Infinity)); // ['a', 'b', 'c']
借助扩展运算符和new Set方法来实现合并数组并且去重
const arr1 = [1,2,3,4]
const arr2 =[3,4,5,6]
const arr3= [new Set([...arr1,...arr2])] //[1,2,3,4,5,6]
ES6中的精确搜索方法find()
const a = [1,2,3,4,5];
const result = a.find( item => {
return item === 3
} )
console.log(result) // 3