Sort key pair value array in TypeScript

Question

Following is dynamic array in TypeScript and I want to sort it by activation date in descending order.

notificationList = [];

notificationList = [ {"Id:11", "ActivationDate":"29-Jan-2018"},
{"Id:21", "ActivationDate":"22-Jan-2018"},
{"Id:8", "ActivationDate":"01-Feb-2018"},
{"Id:10", "ActivationDate":"25-Jan-2018"},
{"Id:12", "ActivationDate":"24-Jan-2018"},
{"Id:05", "ActivationDate":"28-Jan-2018"},
{"Id:04", "ActivationDate":"24-Jan-2018"},
]

I am sorting using below code but it's not giving me expected output.

this.notificationList = this.notificationList.sort(function(a, b): any {
              const dateA = new Date(a['ActivationDate']);
              const dateB = new Date(b['ActivationDate']);
              console.log('dateA -' + dateA);
              console.log('dateB -' + dateB);
              console.log(dateB > dateA);
              return dateB > dateA; //sort by date decending
          });

Any suggestion or input ?

Yes Arvind. It's looks same as what I given above. Although I tried your given code as well but no luck. I don't know what is the issue. — Pushkar Rathod
– Pushkar Rathod, Commented Jan 19, 2018 at 21:09
what you tried using my code can you edit the plunker in it and give me link so i can work on it and help you more — Aravind
– Aravind, Commented Jan 19, 2018 at 21:10

Titian Cernicova-Dragomir · Accepted Answer · 2018-01-20 09:34:22Z

1

The callback to sort should return a number :

let notificationList = [
    { "Id": 11, "ActivationDate": "29 Jan 2018" },
    { "Id": 21, "ActivationDate": "22 Jan 2018" },
    { "Id": 8, "ActivationDate": "01 Feb 2018" },
    { "Id": 10, "ActivationDate": "25 Jan 2018" },
    { "Id": 12, "ActivationDate": "24 Jan 2018" },
    { "Id": 5, "ActivationDate": "28 Jan 2018" },
    { "Id": 4, "ActivationDate": "24 Jan 2018" },
];

notificationList = notificationList.sort(function (a, b): any {
    const dateA = new Date(a['ActivationDate']);
    const dateB = new Date(b['ActivationDate']);
    return dateB > dateA ? 1 : dateB < dateA ? -1 : 0; //sort by date decending
});

Note The date format you use is not officially supported and will only work in Chrome. I removed the - from the dates to convert the dates to a supported format.

edited Jan 20, 2018 at 9:34

answered Jan 19, 2018 at 19:41

Titian Cernicova-Dragomir

253k37 gold badges466 silver badges396 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

Pushkar Rathod Over a year ago

I don't why it's not taking effect. attached screenshot after applying above how it looks like. Don't know why it's not working.

Pushkar Rathod Over a year ago

Your solution is working fine in Chrome but it's not working in IE and FireFox. Any suggestion ?

Titian Cernicova-Dragomir Over a year ago

Sorry not at the PC anymore.. I'll check tomorrow of it isn't too late..

Titian Cernicova-Dragomir Over a year ago

@PushkarRathod The problem is not with the sorting it's with the date format, your date format is not officially supported: w3schools.com/js/js_date_formats.asp. Changed the answer to use a format supported across browsers

Pushkar Rathod Over a year ago

I can't change the date format because it's a requirement. The date format should be DD-MMM-YYYY only. Let me know what can be done to support in all browser.

|

Aravind · Accepted Answer · 2018-01-19 20:11:47Z

0

Your comparison is wrong you should be having < instead of <

this.notificationList.sort((a, b)=> {
  let dateA = new Date(a['ActivationDate']);
  let dateB =  new Date(b['ActivationDate']);
  return dateA < dateB; // sort by descending
});

LIVE DEMO

edited Jan 19, 2018 at 20:11

answered Jan 19, 2018 at 19:46

Aravind

41.7k16 gold badges97 silver badges111 bronze badges

7 Comments

Pushkar Rathod Over a year ago

If I use above mentioned code it throws me following error. Argument of type '(a: any, b: any) => boolean' is not assignable to parameter of type '(a: any, b: any) => number'. Type 'boolean' is not assignable to type 'number'.

Pushkar Rathod Over a year ago

Argument of type '(a: any, b: any) => boolean' is not assignable to parameter of type '(a: any, b: any) => number'. Type 'boolean' is not assignable to type 'number'.

Aravind Over a year ago

@PushkarRathod can you update it to post?. are you available in teamviewer?

Pushkar Rathod Over a year ago

No. I can't do team viewer. But I can mail the whole object which I want to sort. Can you share me your id please ?

Aravind Over a year ago

reach me out in fb @ aravind2109 we can work from there on

|

Collectives™ on Stack Overflow

Sort key pair value array in TypeScript

2 Answers 2

6 Comments

7 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

6 Comments

7 Comments

Your Answer

Sign up or log in

Post as a guest

Related