博客
关于我
数组方法的扩展flat()和flatMap()
阅读量:586 次
发布时间:2019-03-11

本文共 587 字,大约阅读时间需要 1 分钟。

  • flat()将多维数组转化为低维数组
const arr = [1,2,3,4,[5,6]]console.log(arr.flat())        //[1, 2, 3, 4, 5, 6]const arr1 = [1,2,3,4,[5,6,[7,8,9]]]console.log(arr1.flat())       //[1, 2, 3, 4, 5, 6, [7,8,9]] //想将多维数组转成一维数组,则需要参数console.log(arr1.flat(2))      //[1, 2, 3, 4, 5, 6, 7, 8, 9]
  • flatMap()
const arr = [1,2,3,4,5]const result = arr.map(item => [item * 100])    console.log(result)     //返回一个二维数组,如下图

在这里插入图片描述

flatMap()方法将返回的这个二维数组转成一维数组

//flatMapconst arr = [1,2,3,4,5]const result = arr.flatMap(item => [item * 100])    console.log(result)      //[100, 200, 300, 400, 500]

flat()和flatMap()都是ES10中的新特性

转载地址:http://leftz.baihongyu.com/

你可能感兴趣的文章
NO 157 去掉禅道访问地址中的zentao
查看>>
no available service ‘default‘ found, please make sure registry config corre seata
查看>>
No compiler is provided in this environment. Perhaps you are running on a JRE rather than a JDK?
查看>>
no connection could be made because the target machine actively refused it.问题解决
查看>>
No Datastore Session bound to thread, and configuration does not allow creation of non-transactional
查看>>
No fallbackFactory instance of type class com.ruoyi---SpringCloud Alibaba_若依微服务框架改造---工作笔记005
查看>>
No Feign Client for loadBalancing defined. Did you forget to include spring-cloud-starter-loadbalanc
查看>>
No mapping found for HTTP request with URI [/...] in DispatcherServlet with name ...的解决方法
查看>>
No mapping found for HTTP request with URI [/logout.do] in DispatcherServlet with name 'springmvc'
查看>>
No module named 'crispy_forms'等使用pycharm开发
查看>>
No module named cv2
查看>>
No module named tensorboard.main在安装tensorboardX的时候遇到的问题
查看>>
No module named ‘MySQLdb‘错误解决No module named ‘MySQLdb‘错误解决
查看>>
No new migrations found. Your system is up-to-date.
查看>>
No qualifying bean of type XXX found for dependency XXX.
查看>>
No qualifying bean of type ‘com.netflix.discovery.AbstractDiscoveryClientOptionalArgs<?>‘ available
查看>>
No resource identifier found for attribute 'srcCompat' in package的解决办法
查看>>
no session found for current thread
查看>>
no such file or directory AndroidManifest.xml
查看>>
No toolchains found in the NDK toolchains folder for ABI with prefix: mips64el-linux-android
查看>>