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This topic created in 2187 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
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1
aogu555 May 7, 2020  1
JSON.stringify(arr) === '[]'
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2
aogu555 May 7, 2020
我来个不优雅的 hhh
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3
cnmllll May 7, 2020
arr.length === 0
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4
dragonbuf May 7, 2020
isEmpty(arr) {return arr.length === 0}
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5
SilentDepth May 7, 2020
arr.length === 0
直观、无歧义 |
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6
marcong95 May 7, 2020 1
import isNonEmptyArray from 'is-non-empty-array'
!isNonEmptyArray(arr) //  |
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7
raincode May 7, 2020
if(!arr.length){}
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8
Mohanson May 7, 2020 via Android 10
写一个 isEmpty 包放 npm 上，然后 import 它
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9
ooops May 7, 2020
定义个方法比较优雅啊 arr.isEmpty()
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10
wuhaoworld May 7, 2020
@Mohanson 这个比较讽刺
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11
myd May 7, 2020
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 |
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12
guiling May 7, 2020 via Android
来个骚操作，忽略特殊情况
if(arr[0]){} |
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14
liuzhiyong May 7, 2020 via Android
第一个，直接判断是否为零。话说这东西优先考虑语义清晰。
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15
Ncanback May 7, 2020 1
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 ？ |
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16
newmlp May 7, 2020
就他妈一个 if 判断，有啥性能优化啊，我艹
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17
weixiangzhe May 7, 2020
!arr.length
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18
JerryCha May 7, 2020
((arr)=>arr.length===0)(arr)
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19
iamjoyhe May 7, 2020
这也能优雅？
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20
zfz001 May 7, 2020
arr.length === 0
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21
zfz001 May 7, 2020
花里胡哨😀
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22
printese May 7, 2020 via iPhone
(arr.length|0x0) == 0
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23
JohnLou May 7, 2020
屁事真多
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25
chenliangngng OP |
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26
Wap May 8, 2020
!arr[0]
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27
jipf9046522 Dec 4, 2020
@newmlp 有点意思
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