[js 将一维数组按指定长度转为二维数组] https://xugaoyi.com/pages/f1acb712033ac8da/

pages.js

function pages(arr, len) {
    const pages = []
    arr.forEach((item, index) => {
        const page = Math.floor(index / len)
        if (!pages[page]) {
            pages[page] = []
        }
        pages[page].push(item)
    })
    return pages
}

// 使用
const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9]
console.log(pages(arr, 3)) // [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
console.log(pages(arr, 8)) // [[1, 2, 3, 4, 5, 6, 7, 8], [9]]