如何使用JSON格式的日期过滤数据

How to filter the data using date from JSON format

本文关键字:日期 过滤 数据 格式 何使用 JSON      更新时间:2023-09-26

我想使用日期过滤,但数据是JSON格式。我如何在JavaScript中使用日期过滤大型数据集?

例子:

data=[{date:'22-12-2014',name:'selva'},{date:'10-10-2010',name:'raja'},{date:'11-11- 2011',name:'suresh'}]

如果您只是想按时间筛选数据,您可以像这样查看数组中的所有对象:

var filteredData = [];
for(var index in data) {
    var obj = data[index];
    var date = parseDate(obj.date);
    //Filter dates from 2011 and newer
    if(date > new Date(2011, 0, 1))
        filteredData.push(obj);
}
function parseDate(dateStr) {
    var date = dateStr.split('-');
    var day = date[0];
    var month = date[1] - 1; //January = 0
    var year = date[2];
    return new Date(year, month, day); 
}
//Filtered data now contains:
// [{"date":"22-12-2014","name":"selva"},{"date":"11-11- 2011","name":"suresh"}] 

我确信您可以更好地解析日期,例如,通过以date构造函数接受的格式定义日期。

要获取与特定日期匹配的元素集,您可以使用filter将它们提取到一个新数组中。

function getByDate(date){
  return data.filter(function (el) {
    return el.date == date;
  });
}
var arr = getByDate('11-11-2011');

要按日期对数据集进行排序,首先需要将日期字符串转换为JS日期对象。这需要稍微调整日期字符串,以便可以正确解析。

function reformatDate(date) {
  return arr = date.split('-').reverse();
}
var sortByDate = function (a, b) {
  return new Date(reformatDate(a.date)) - new Date(reformatDate(b.date));
};
data.sort(sortByDate);

JSFiddle演示

我使用的日期格式是MM/DD/YY。下面是完整的示例-

var data=[
  {date:'02/10/2018',name:'date is 10'},
  {date:'02/14/2018',name:'date is 14'},
  {date:'02/16/2018',name:'date is 16'},
  {date:'02/20/2018',name:'date is 20'},
  {date:'02/24/2018',name:'date is 24'},
  {date:'02/26/2018',name:'date is 26'},
  {date:'02/30/2018',name:'date is 30'},
  {date:'03/01/2018',name:'date is 01'},
  {date:'03/05/2018',name:'date is 05'},
  {date:'02/23/2018',name:'date is name 23'},
]

  var today            = new Date();
  var todayTime        = new Date().getTime();
  var days_after_20    = new Date().setDate(today.getDate()+20);
  var days_before_5    = new Date().setDate(today.getDate()-5);
  var result = data.filter(function (item) {
     var itemTime = new Date(item.date).getTime()
     return itemTime >= days_before_5 && itemTime <= days_after_20; 
  })
console.log(result);

要获取与某个日期匹配的元素集,可以使用filter将它们提取到一个新的数组中。

var tempArray=   data.filter(function (d, i) {
    return d >= startDate && d <= endDate;
})