Compare Dates in Angular 2

Question

I'm trying to figure out how best to compare dates in Angular 2 and TypeScript 1.8.7.

Given:

startDate: Date;
endDate: Date;

if(this.startDate.getUTCMilliseconds() === this.endDate.getUTCMilliseconds()){
     //do stuff here
} else {
     // do something else here
}

This will return an error like "startDate.getUTCMilliseconds is not a function..."

Does somebody have a best practice? Thanks,

`{{+startDate == +endDate}}` (unary `+`) doesn't work in binding expressions though https://github.com/angular/angular/issues/7964 — Günter Zöchbauer, Apr 20 '16 at 06:23
See also https://plnkr.co/edit/EFsbEl?p=preview (3 and 4 demonstrated how unary `+` works differently when applied in template (no effect) and in code. — Günter Zöchbauer, Apr 20 '16 at 06:33

score 1 · Answer 1 · answered Apr 19 '16 at 21:57

1

Date object method to get milliseconds is called getTime.

answered Apr 19 '16 at 21:57

kemsky

14,727
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Nice try. But, we're dealing with javascript dates. This is way too logical. If there's some interference from Typescript, I don't have a clue. Intellisense is comfortable with getTime, but Chrome is screaming that getTime is not a function. – LargeDachshund Apr 20 '16 at 03:53
`someDate.getTime()` works fine for me in Chrome. – Günter Zöchbauer Apr 20 '16 at 06:20
@LargeDachshund Did you solve this? I have the same problem – Wouter Vanherck May 02 '17 at 12:43
Wouter, I have not. I needed this logic for field validation. It became such a pain that I gave up. What's so painful is that you'd think something like time would be quite determinant. Instead, there are tons of formatted dates that pass for a date. So, I took a pass on this issue. Thanks for making me relive this nightmare. – LargeDachshund May 03 '17 at 23:06
`getTime` and any other method of `Date` type does not work for me – Amir Choubani Jun 07 '18 at 10:21

score 1 · Answer 2 · answered Apr 20 '16 at 00:42

1

You can compare Date objects directly, with operators like <, >, and ==.

this.startDate == this.endDate

answered Apr 20 '16 at 00:42

Matt C

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While this appears to be the right answer, I can't give the "green check mark" because of this test: if this.endDate = new Date("0001-01-01T00:00:00") and this.startDate is the minimum date, the condition should return true. Instead, the condition returns false. This is fitting because dates in Java and javascript are inscrutable. – LargeDachshund Apr 20 '16 at 03:48
@LargeDachshund What test? – Matt C Apr 20 '16 at 03:49

score 0 · Answer 3 · answered Apr 20 '16 at 00:46

0

I know it's irrelevant and not what you asked for, but use angular-moment / momentjs. Dates in JS are a complete mess.

answered Apr 20 '16 at 00:46

user1027620

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Dates in general, seem like a complete mess. If there's a best practice for boxing/unboxing dates in TypeScript objects, I'm all ears. That's what I'm driving at. – LargeDachshund Apr 20 '16 at 03:19

Compare Dates in Angular 2

3 Answers3