Sort Objects By datetime in JavaScript-CodePudding

I have contacts that have SMS messages associated with them. Each sms record has properties such as time. Time is an timestamp string formatted as this example

2022-04-29T16:10:43-06:00

I am trying to sort this array of sms messages so that the latest one is the last one and the earliest one is the first one in the array. I thought I had it nailed down but apparently I don't. Its still not perfectly sorting at all.

this.getRecent()
    .then(contacts => {
        const sorted = contacts.map(contact => {
            contact.sms = contact.sms.sort((a,b) => (a.time.localeCompare(b.time));
            return contact;
        });
        // rest of code here
    })
    .catch(err => this.handleError(err));

CodePudding user response：

Based on your question, I'm making the assumption that the contact.sms object contains an array of objects where time is a string (localeCompare is called). Since dates can have operators applied to them, you can sort them like any number.

const dates = [
  new Date("2022-04-29T16:10:43-06:00"),
  new Date("2023-04-29T16:10:43-06:00"),
  new Date("2022-01-29T16:10:43-06:00")
]

console.log(dates)

dates.sort((a, b) => a - b)

console.log(dates)

In your case,

// Sorts dates where the least recent is first.
contact.sms = contact.sms.sort((a,b) => new Date(a.time) - new Date(b.time));

CodePudding user response：

You can parse them to a Date and compare the milliseconds:

contact.sms.sort((a,b) => new Date(a.time) - new Date(b.time));

Or swap a and b if you want to reverse the order.

CodePudding user response：

The date seems to be valid ISO 8601 format so you can just use the following in sort function:

return Date.parse(a.time) - Date.parse(b.time)