如何使用 javascript/jquery 从数组中获取最大和最小日期？

Question

我想从一个 json 数组中获取最小和最大日期：

我的代码

$.getJSON(url, function (data) {
    var dates = Object.keys( data['data']['horodate'] ).map(function ( key ) {
        return data['data']['horodate'][key].replace(/\-/g,'/' ) 
    });
    var min = new Date(Math.min.apply( null, dates ));
    var max =  new Date(Math.max.apply( null, dates));
});

data 数组是：

Array [ 
    "2016/10/13 00:00:00", 
    "2016/10/13 00:30:00", 
    "2016/10/13 01:00:00", 
    "2016/10/13 01:30:00", 
    "2016/10/13 02:00:00", 
    "2016/10/13 02:30:00", 
    "2016/10/13 03:00:00", 
    "2016/10/13 03:30:00", 
    "2016/10/13 04:00:00", 
    "2016/10/13 04:30:00"
]

但我有一个错误：Invalid date。你能帮我吗？

Answer 1

使用 Array#sort 和自定义排序功能并获取最后（最大）和第一个（最小）值。

data = ["2016/10/13 00:00:00", "2016/10/13 00:30:00", "2016/10/13 01:00:00", "2016/10/13 01:30:00", "2016/10/13 02:00:00", "2016/10/13 02:30:00", "2016/10/13 03:00:00", "2016/10/13 03:30:00", "2016/10/13 04:00:00", "2016/10/13 04:30:00"];

var sorted = data.slice() // copy the array for keeping original array with order
  // sort by parsing them to date
  .sort(function(a, b) {
    return new Date(a) - new Date(b);
  });

// get the first and last values
console.log(
  'max :', sorted.pop(), 'min :', sorted.shift()
);

---

或者使用简单的 Array#forEach 循环。

data = ["2016/10/13 00:00:00", "2016/10/13 00:30:00", "2016/10/13 01:00:00", "2016/10/13 01:30:00", "2016/10/13 02:00:00", "2016/10/13 02:30:00", "2016/10/13 03:00:00", "2016/10/13 03:30:00", "2016/10/13 04:00:00", "2016/10/13 04:30:00"];

// initially set max and min as first element
var max = data[0],
  min = data[0];

// iterate over array values and update min & max
data.forEach(function(v) {
  max = new Date(v) > new Date(max)? v: max;
  min = new Date(v) < new Date(min)? v: min;
});

console.log('max :', max, 'min :', min);

Answer 2

IMO，您应该使用 new Date(value)

您的代码似乎没有任何问题。

得到Invalid date的原因是你没有将日期转换为日期对象，你需要将它转换成JavaScript日期new Date()。

Date 对象让您可以处理日期（年、月、日、小时、分钟、秒和毫秒）

var datesNew=["2016/10/13 00:00:00", "2016/10/13 00:30:00", "2016/10/13 01:00:00", "2016/10/13 01:30:00", "2016/10/13 02:00:00", "2016/10/13 02:30:00", "2016/10/13 03:00:00", "2016/10/13 03:30:00", "2016/10/13 04:00:00", "2016/10/13 04:30:00"];
//This will convert your date into Date object
$.each(datesNew, function(key, value){
    dates.push(new Date(value));
});
var min = dates.reduce(function (a, b) { return a < b ? a : b; }); 
var max = dates.reduce(function (a, b) { return a > b ? a : b; }); 

var datesNew=["2016/10/13 00:00:00", "2016/10/13 00:30:00", "2016/10/13 01:00:00", "2016/10/13 01:30:00", "2016/10/13 02:00:00", "2016/10/13 02:30:00", "2016/10/13 03:00:00", "2016/10/13 03:30:00", "2016/10/13 04:00:00", "2016/10/13 04:30:00"];
var dates=[];
$.each(datesNew, function(key, value){
    //Conver date in Date object
    dates.push(new Date(value));
});

var min = new Date(Math.min.apply( null, dates));
var max =  new Date(Math.max.apply( null, dates));
//var min = dates.reduce(function (a, b) { return a < b ? a : b; }); 
//var max = dates.reduce(function (a, b) { return a > b ? a : b; }); 
console.log(new Date(min).toString());
console.log(new Date(max).toString());

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