根据日期对对象数组进行排序

Question

I have an array of objects similar to...

[
  {
    date: "26/11/2016"
    hourlyRate: 50
    hoursWorked: 10
    name: "Mr G"
    natInsNumber: "GG845893G"
  },
  {
    date: "14/10/2016"
    hourlyRate: 50
    hoursWorked: 10
    name: "Mr A"
    natInsNumber: "GG845893G"
  },
  {
    date: "11/09/2016"
    hourlyRate: 50
    hoursWorked: 10
    name: "Mr H"
    natInsNumber: "GG845893G"
  },
  {
    date: "26/10/2016"
    hourlyRate: 50
    hoursWorked: 10
    name: "Mr L"
    natInsNumber: "GG845893G"
  }
]

I need to sort this list based on the most recent dates.

Based on similar problems I have seen this is my code for the solution, the array is being passed in as the records argument...

function sortRecords (records) {

  var sorted = records.sort(function(a, b){
    return new Date(a.date) - new Date(b.date); 
  });

  return sorted;

}

Can anyone advise on why this is not working? I am just getting back the same unsorted array....

Answer 1

That's because your date String can't be parsed as a valid date, you'd need to rearrange the string you are passing to new Date() . For example the following would produce a parsable date:

function rearrangeDate(dateString) {
    var r = dateString.split('/');
  return r[1] + "/" + r[0] + "/" + r[2];
}

which you then can use

function sortRecords (records) {

  var sorted = records.sort(function(a, b){
    return new Date(rearrangeDate(a.date)) - new Date(rearrangeDate(b.date)); 
  });

  return sorted;

}

Answer 2

try this

    let sorted = 
     [{
        date: "26/11/2016",
        hourlyRate: 50,
        hoursWorked: 10,
        name: "Mr G",
        natInsNumber: "GG845893G"
    },
    {
        date: "14/10/2016",
        hourlyRate: 50,
        hoursWorked: 10,
        name: "Mr A",
        natInsNumber: "GG845893G"
    },
    {
        date: "11/09/2016",
        hourlyRate: 50,
        hoursWorked: 10,
        name: "Mr H",
        natInsNumber: "GG845893G"
    },
    {
        date: "26/10/2016",
        hourlyRate: 50,
        hoursWorked: 10,
        name: "Mr L",
        natInsNumber: "GG845893G"
    }
];

function CreateDate(dateString) {
    var arr = dateString.split('/');
    return new Date(arr[2] , arr[1], arr[0]);
}

function sortRecords(records) {    
    var sorted = records.sort(function (a, b) {        
        return CreateDate(a.date) > CreateDate(b.date);
    });
    console.log(sorted);
}

sortRecords(sorted);

Produces below output:

Answer 3

you could also sort date on the basis of the year-month-day by reversing the current day-month-year :

 var list = [ { date: "26/11/2016", hourlyRate: 50, hoursWorked: 10, name: "Mr G", natInsNumber: "GG845893G" }, { date: "30/10/2016", hourlyRate: 50, hoursWorked: 10, name: "Mr A", natInsNumber: "GG845893G" }, { date: "11/09/2016", hourlyRate: 50, hoursWorked: 10, name: "Mr H", natInsNumber: "GG845893G" }, { date: "26/10/2016", hourlyRate: 50, hoursWorked: 10, name: "Mr L", natInsNumber: "GG845893G" } ] var result = list.sort((a,b) => a.date.split("/").reverse().join("") - b.date.split("/").reverse().join("")); console.log(result);