问题描述
我有一个数组看起来像：
var v = ["07/27/2015", "07/28/2015", "08/29/2015", "08/29/2015", "07/27/2016"]
我想要做的是将其动态地排序为一个新的空数组nv 。
排序完成后， nv应该看起来像。
var nv = [["07/27/2015", "07/28/2015"], ["08/29/2015", "08/29/2015"], ["07/27/2016"]]
这样可以排序吗？
1楼
Andreas
4
已采纳
2015-07-25 16:40:11
var dates = ["07/27/2015", "07/28/2015", "08/29/2015", "08/29/2015", "07/27/2016"];
var groupedDates = dates.reduce(function(l, r) {
var keyParts = r.split("/"),
key = keyParts[2] + keyParts[0];
if (typeof l[key] === "undefined") {
l[key] = [];
}
l[key].push(r);
return l;
}, {});
var result = Object.keys(groupedDates)
.sort(function(a, b) { return Number(a) - Number(b); })
.map(function(key) {
return groupedDates[key];
});
console.log(result); // [["07/27/2015","07/28/2015"],["08/29/2015","08/29/2015"],["07/27/2016"]]
2楼
Daniel Kobe
2
2015-07-25 16:42:40
因此，我做了一个函数，将日期放入属性为月和年的对象中。 日期被放入其月份和年份的属性中。 然后，该函数创建一个数组，并为该函数的每个属性创建一个内部数组。 在每个内部数组中，它放置该属性的所有日期。 我认为这种方法比嵌套循环更有效。
// function takes an array of dates in the following format MM/DD/YYYY
// outputs an array with inner arrays of dates. Each inner array contains dates of the same month and year
var groupDates = function(dateArray) {
// create object to organize dates by month and year
var dateHash = {};
// the array that is outputted
var groupedDates = [];
//for every date in dateArray
dateArray.forEach(function(currentDate) {
// check if any other dates with the same month and year exist in the dateHash object
if (dateHash[currentDate.substr(0, 2) + currentDate.substr(6)]) {
// if other dates exist, push the date to the array in the dateHash property for the dates current month and year
dateHash[currentDate.substr(0, 2) + currentDate.substr(6)].push(currentDate);
} else {
// otherwise create a property for the dates month and year and store the current date in an array in the propery
dateHash[currentDate.substr(0, 2) + currentDate.substr(6)] = [currentDate];
}
});
// for every propery in the datehash, push the array of dates into the grouped dates array
for (var dateGroup in dateHash) {
groupedDates.push(dateHash[dateGroup]);
}
return groupedDates;
};
var dateArray = ["07/27/2015", "07/28/2015", "08/29/2015", "08/29/2015", "07/27/2016"];
console.log(groupDates(dateArray));
3楼
Tarek
0
2015-07-25 16:40:00
您可以遍历该数组并检查每个值是否具有新的月份和年份，或者已包含在排序数组中。 我认为像这样未经测试的代码：
new_arr = new Array();
for(var i=0; i < v.length; i++){
var this_date = new Date(v[i]);
var month_and_year = this_date.getMonth() + this_date.getFullYear();
if(typeof(new_arr[month_and_year]) == 'undefined'){
new_arr[month_and_year] = new Array();
}
new_arr[month_and_year].push(v[i])
}