本文整理了一些实用的 JavaScript 单行函数，特别好用，能让你更快的完成工作，抽出更多的时间陪你的女朋友。话不多说，我们开始吧！
时间和日期
检查日期是否合法
constisDateValid=(...val)=>!Number.isNaN(newDate(...val).valueOf())console.log(isDateValid("December17,199503:24:00"))//true检查日期是否为周末
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一
查找日期位于一年中的第几天
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//272计算2个日期之间相差多少天
constdayDif=(date1,date2)=>Math.ceil(Math.abs(date1.getTime()-date2.getTime())/86400000)console.log(dayDif(newDate("2021-10-1"),newDate("2021-9-30")))//1时间处理
consttimeFromDate=date=>date.toTimeString().slice(0,8)console.log(timeFromDate(newDate()))console.log(timeFromDate(newDate(2021,0,10,17,30,0)))//14:23:36//17:30:00
数字
检查数字是偶数还是奇数
constisEven=(num)=>num%2===0console.log(isEven(5))//false
多个数字的平均值
constaverage=(...args)=>args.reduce((a,b)=>a+b)/args.lengthconsole.log(average(1,2,3,4,5))//3
两个数字之间生成一个随机数
constrandom=(min,max)=>Math.floor(Math.random()*(max-min+1)+min)console.log(random(1,50))//couldbeanythingfrom1-50
字符串
翻转字符串
constreverse=str=>str.split('').reverse().join('')console.log(reverse('helloworld'))//dlrowolleh首字母大写字符串
constcapitalize=(str)=>str.charAt(0).toUpperCase()+str.slice(1)console.log(capitalize('helloworld'))在结尾处截断字符串
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一0
从中间截断字符串
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一1
生成随机字符串(唯一ID)
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一2
数组
获取数组中的唯一值(数组去重)
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一3
检查变量是否为数组
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一4
打乱数组
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一5
校验数组是否为空
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一6
合并多个数组的不同方法
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一7
布尔值
随机获取布尔值
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一8
切换布尔
constisWeekend=(date)=>[0,6].indexOf(date.getDay())!==-1console.log(isWeekend(newDate(2021,5,21)))//falseconsole.log(isWeekend(newDate(2021,5,20)))//true//当前日期为2021.6.21周一9
变量交换
交换两个变量(分号必须有)
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2720短路
Longhand
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2721Shorthand
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2722获取 JavaScript 语言的实际类型
方法 A
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2723方法 B
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2724颜色
颜色RGB转十六进制
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2725生成随机十六进制颜色
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2726Cookie
获取浏览器Cookie的值
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2727清除全部Cookie
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2728从 URL 获取查询参数
方法 A
constdayOfYear=(date)=>Math.floor((date-newDate(date.getFullYear(),0,0))/1000/60/60/24)//三个参数输入具体日期月份要减一console.log(dayOfYear(newDate(2021,8,29)))console.log(dayOfYear(newDate("2021-9-29")))console.log(dayOfYear(newDate()))//272//272//2729方法 B
constdayDif=(date1,date2)=>Math.ceil(Math.abs(date1.getTime()-date2.getTime())/86400000)console.log(dayDif(newDate("2021-10-1"),newDate("2021-9-30")))//10移动端
检查用户是否在Apple设备上
constdayDif=(date1,date2)=>Math.ceil(Math.abs(date1.getTime()-date2.getTime())/86400000)console.log(dayDif(newDate("2021-10-1"),newDate("2021-9-30")))//11检查用户的设备是否处于黑暗模式
constdayDif=(date1,date2)=>Math.ceil(Math.abs(date1.getTime()-date2.getTime())/86400000)console.log(dayDif(newDate("2021-10-1"),newDate("2021-9-30")))//12其他
滚动到页面顶部
constdayDif=(date1,date2)=>Math.ceil(Math.abs(date1.getTime()-date2.getTime())/86400000)console.log(dayDif(newDate("2021-10-1"),newDate("2021-9-30")))//13将文字复制到剪贴板
constdayDif=(date1,date2)=>Math.ceil(Math.abs(date1.getTime()-date2.getTime())/86400000)console.log(dayDif(newDate("2021-10-1"),newDate("2021-9-30")))//14获取用户选择的文本
constdayDif=(date1,date2)=>Math.ceil(Math.abs(date1.getTime()-date2.getTime())/86400000)console.log(dayDif(newDate("2021-10-1"),newDate("2021-9-30")))//15检查当前选项卡是否在视图/焦点内
constdayDif=(date1,date2)=>Math.ceil(Math.abs(date1.getTime()-date2.getTime())/86400000)console.log(dayDif(newDate("2021-10-1"),newDate("2021-9-30")))//16