时间戳

首页 > 解决方案 > 用javascript修改日期字符串

javascript - 用javascript修改日期字符串

问题描述

我有一些事件会拉出它的日期，如下所示：

6 月 20 日上午 10 点至 9 月 5 日晚上 10 点

9 月 28 日中午 - 下午 4 点

我无法控制它返回的内容，因此我需要通过 javascript 将其删除

我需要删除时间并用 3 个字符版本替换月份，如下所示：

6 月 20 日 - 9 月 5 日

我已经开始这样做了，但我不知道如何删除时间，因为它可能被格式化为 AM/PM 或 MIDNIGHT/NOON

这是我到目前为止所做的：

var dateExample = '2nd August 9am - 27th September midnight';
function trimDate(date){
  const dateArray = date.split(' ');
  var months = [['January', 'Jan'], ['February', 'Feb'], ['March', 'Mar'], ['April', 'Apr'], ['May', 'May'], ['June', 'Jun'], ['July', 'Jul'], ['August', 'Aug'], ['September', 'Sep'], ['October', 'Oct'], ['November', 'Nov'], ['December', 'Dec']];

  for (let x = 0; x < months.length; x++){
    let i = dateArray.findIndex(d => d === months[x][0]);
    if (i > -1) dateArray.splice(i, 1, months[x][1]);
  }
  console.log(dateArray.join(' '));
}

trimDate(dateExample);

标签： javascript

解决方案

使用正则表达式可以更简单地替换日期：

var dateExample = '2nd August 9am - 27th September midnight';
var re = /January|February|March|April|May|June|July|August|September|October|November|December/gi;
var replaced = dateExample.replace(re, m => m.substring(0,3));
console.log(replaced)

您可以使用类似的技巧，正则表达式可能会更复杂一些：

var dateExample = '2nd August 9am- 27th September midnight';
var datesRegex = /January|February|March|April|May|June|July|August|September|October|November|December/gi;


var timesRegex = /\w*([0-9]{1,2}(am|pm|AM|PM))|(noon|midnight)\w*/gi
var replaced = dateExample.replace(datesRegex, m => m.substring(0,3))
                           .replace(timesRegex,'');
console.log(replaced)

把它们放在一起

function clean(input){

  var datesRegex = /January|February|March|April|May|June|July|August|September|October|November|December/gi;
  var timesRegex = /\w*([0-9]{1,2}(am|pm|AM|PM)\w*)|(noon|midnight)/gi
  return input.replace(datesRegex, m => m.substring(0,3))
                             .replace(timesRegex,'');
}

// test cases
console.log(clean("20th June 10am - 5th September 10pm"));
console.log(clean("2nd August 9am - 27th September midnight"));
console.log(clean("2nd August noon - 27th September midnight"));

推荐阅读