String date to unix timestamp

I m working on a scheduled TV on a raspberry pi (raspbian) in javascript/node.js

I extract the information of what to play in a .smil file, and one of the field is scheduled, wich is a string of the format "YYYY-MM-DD hh:mm:ss"

To make comparison between them and the system time, I would like to convert it in UNIX timestamp.

Is there a better way than a function like this one:

function (stime){
    var time=0, cache=0, scache;

    scache=stime.substr(0, 4);
    cache=parseInt(scache);
    time=cache*365*24*60*60;

    ...

    return time;
}

And so on for mounth, day...?

May be this can help

var date = new Date('2009-07-15 00:00:00'.split(' ').join('T'))

that will give you date object and to get timestamp from it you can do

date.getTime() / 1000

dividing by 1000 because getTime will give timestamps in milliseconds