无法理解此代码[JavaScript，日期和获取时区]

Question

Please help me to understand this code :-

function seconds_with_leading_zeros(dt)   
{   
  return /\((.*)\)/.exec(new Date().toString())[1];  
}  

dt = new Date();   
console.log(seconds_with_leading_zeros(dt));   

dt = new Date(1989, 10, 1);   
console.log(seconds_with_leading_zeros(dt)); 

It is suppose to show user's time zone.

Answer 1

new Date().toString() returns a string like "Wed Mar 29 2017 15:37:26 GMT+0200 (West-Europa (zomertijd))" The timezone is inside the round brackets ().

return /\\((.*)\\)/.exec("date and time (timezone)")[1]; returns whatever is inside the brackets. In this case it will return the word "timezone"

That's as good as i can explain it :)