Object.fromEntries()

方法 Object.fromEntries() 把键值对列表转换为一个对象，这个方法是和 Object.entries() 相对的。

    Object.fromEntries([
        ['foo', 1],
        ['bar', 2]
    ])
    // {foo: 1, bar: 2}

案例1：Object 转换操作

    const obj = {
        name: 'imooc',
        course: 'es'
    }
    const entries = Object.entries(obj)
    console.log(entries)
    // [Array(2), Array(2)]

    // ES10
    const fromEntries = Object.fromEntries(entries)
    console.log(fromEntries)
    // {name: "imooc", course: "es"}

案例2：Map 转 Object

    const map = new Map()
    map.set('name', 'imooc')
    map.set('course', 'es')
    console.log(map)

    const obj = Object.fromEntries(map)
    console.log(obj)
    // {name: "imooc", course: "es"}

案例2：过滤

course表示所有课程，想请求课程分数大于80的课程组成的对象：

    const course = {
        math: 80,
        english: 85,
        chinese: 90
    }
    const res = Object.entries(course).filter(([key, val]) => val > 80)
    console.log(res)
    console.log(Object.fromEntries(res))

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• proposal-object-from-entries (opens new window)