SHUIYI_24的博客

Promise.all和Promise.race

1.将字符串转为真正的数组。[...'hello']// [ "h", "e", "l", "l", "o" ]2.合并数组arr1.push(...arr2) // 把arr2合并到arr1的后面arr1.unshift(...arr2) //把arr2合并到arr1的前面如果你想在数组内合并数组，你可以像下面这样做：var arr1 = ['two', 'three'];var arr2 = ['one', ...arr1, 'four', 'five'];3.复制