某面试题

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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>

</body>

</html>
<script>

    /* 
        cookie字符串转对象
        输入‘foo=bar;equation=E%3Dmc%5E2’
    */
    const parseCookie = (str = '') => {
        return str.split(';')?.reduce((a, b) => {
            let key = /w+(?==)/.exec(b)
            let val = /(?<==)[w%]+/.exec(b)[0]
            let obj = {
                [key]: unescape(val)
            }
            return { ...a, ...obj }
        }, {})
    }
    // console.log(parseCookie('foo=bar;equation=E%3Dmc%5E2'))
    /* 
        找出对象中符合的项
        输入{a:1,b:'2',c:3} 条件item=>typeof x ==='string'
        输入{b:'2'}
    */
    const pickBy = (obj, fn) => {
        let _obj = {};
        for (let i in obj) {
            fn(obj[i]) && (_obj[i] = obj[i])
        }
        return _obj
    }
    pickBy({ a: 1, b: '2', c: '3' }, item => typeof item === 'string')
    /* 
        手机号加密
        输入 15806516662，“*”，3,4  从第三位开始的后四位替换成*
        输出158****6662
    */
    const secretMobile = (phone = '', bol = "*", strNum = 3, size = 4) => {
        let _phone = phone + ''
        return _phone.replace(new RegExp(`(?<=.{${strNum}})[0-9]{${size}}`), (match) => {
             let i=''
            while (size--) {
                i += bol
            }
            return i
        })
       
    }
    let a = secretMobile(15806516662, '*', 3,4)
    console.log(a)
</script>

1、路在何方？路在脚下 2、何去何从？每个人都在探索，未来的方向在何处。如果说某些方向是世人已经公认的，那么就先按照公认的去走吧（ps:站在巨人的肩膀上看世界会清晰）。如果说方向，当今世人还不清晰准确。那么就大胆往前走吧，对与错并不重要。心中的方向更加重要。