Question

I suppose this is absolute novice question in javascript.

I want to know what do ‘-‘ mean in javascript date.

Example: new Date(2010, 12 – 1, 10, 22, 00, 00);

What does 12 – 1 say in the above.

Thanks

Answer 1

It’s subtracting one to get 11.

Why? It’s usually the result of an earlier month number being “off” one, because .getMonth() is 0-based, where other date parts are 1-based. The signature for Date() looks like this:

new Date(year, month, date, hour, minute, second, millisecond)

…but the month parameter is 0-11, where the year and date parameters are 1-based. You think of 12 as December, but being 0-based, it’s 11 not 12…the code style you’re seeing is one way to express that or at least make you go “wait a second…” and see that it’s not November, as you’d intuitively think if the author just put “11” there.