Get week of year in JavaScript like in PHP

Question

How do I get the current weeknumber of the year, like PHP\'s date(\'W\')?

It should be the ISO-8601 week number of year, weeks starting

Answer 1

Shortest workaround for Angular2+ DatePipe, adjusted for ISO-8601:

import {DatePipe} from "@angular/common";

public rightWeekNum: number = 0;
  
constructor(private datePipe: DatePipe) { }
    
calcWeekOfTheYear(dateInput: Date) {
  let falseWeekNum = parseInt(this.datePipe.transform(dateInput, 'ww'));
  this.rightWeekNum = (dateInput.getDay() == 0) ? falseWeekNumber-1 : falseWeekNumber;
}