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chenliangngng

判断数组 length 等于 0,怎么编码比较优雅?与 0 比较还是取反?

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  •   chenliangngng · May 7, 2020 · 6026 views
    This topic created in 2372 days ago, the information mentioned may be changed or developed.

    arr.length === 0

    !arr.length

    考虑语义、执行效率、代码量等

    27 replies  •  2020-12-04 16:02:46 +08:00
    aogu555
    aogu555
    May 7, 2020❤️1
    1
    JSON.stringify(arr) === '[]'
    aogu555
    aogu555
    May 7, 2020
    2
    我来个不优雅的 hhh
    cnmllll
    cnmllll
    May 7, 2020
    3
    arr.length === 0
    dragonbuf
    dragonbuf
    May 7, 2020
    4
    isEmpty(arr) {return arr.length === 0}
    SilentDepth
    SilentDepth
    May 7, 2020
    5
    arr.length === 0

    直观、无歧义
    marcong95
    marcong95
    May 7, 2020❤️1
    6
    import isNonEmptyArray from 'is-non-empty-array'

    !isNonEmptyArray(arr) //
    raincode
    raincode
    May 7, 2020
    7
    if(!arr.length){}
    Mohanson
    Mohanson
    May 7, 2020 via Android❤️10
    8
    写一个 isEmpty 包放 npm 上,然后 import 它
    ooops
    ooops
    May 7, 2020
    9
    定义个方法比较优雅啊 arr.isEmpty()
    wuhaoworld
    wuhaoworld
    May 7, 2020
    10
    @Mohanson 这个比较讽刺
    myd
    myd
    May 7, 2020
    11
    arr.length === 0

    这样写比较好理解,另外,性能瓶颈也不会在这个地方
    guiling
    guiling
    May 7, 2020 via Android
    12
    来个骚操作,忽略特殊情况
    if(arr[0]){}
    anjianshi
    anjianshi
    May 7, 2020
    13
    @guiling 这个问题很大。数组内容是 [false], [0], [''] 咋办
    liuzhiyong
    liuzhiyong
    May 7, 2020 via Android
    14
    第一个,直接判断是否为零。话说这东西优先考虑语义清晰。
    Ncanback
    Ncanback
    May 7, 2020❤️1
    15
    你这个说的....
    师爷,你来翻译翻译,什么叫做:判断数组 length 等于 0 ? 什么 tmd 叫做:判断数组 length 等于 0 ?
    newmlp
    newmlp
    May 7, 2020
    16
    就他妈一个 if 判断,有啥性能优化啊,我艹
    weixiangzhe
    weixiangzhe
    May 7, 2020
    17
    !arr.length
    JerryCha
    JerryCha
    May 7, 2020
    18
    ((arr)=>arr.length===0)(arr)
    iamjoyhe
    iamjoyhe
    May 7, 2020
    19
    这也能优雅?
    zfz001
    zfz001
    May 7, 2020
    20
    arr.length === 0
    zfz001
    zfz001
    May 7, 2020
    21
    花里胡哨😀
    printese
    printese
    May 7, 2020 via iPhone
    22
    (arr.length|0x0) == 0
    JohnLou
    JohnLou
    May 7, 2020
    23
    屁事真多
    guiling
    guiling
    May 7, 2020
    24
    @anjianshi 所以说忽略特殊情况啊,一般都是判断对象数组的

    怎么用看个人,要稳定&可读性的话还是按标准的来吧
    chenliangngng
    chenliangngng
    OP
    May 8, 2020 via Android
    25
    @Mohanson 8#
    @Ncanback 15#
    哈哈,我笑了
    Wap
    Wap
    May 8, 2020
    26
    !arr[0]
    jipf9046522
    jipf9046522
    Dec 4, 2020
    27
    @newmlp 有点意思
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