week-number

问题 Anyone know an easy way to get the date of the first day in the week (monday here in Europe). I know the year and the week number? I\'m going to do this in C#. 回答1: I had issues with the solution by @HenkHolterman even with the fix by @RobinAndersson. Reading up on the ISO 8601 standard resolves the issue nicely. Use the first Thursday as the target and not Monday. The code below will work for Week 53 of 2009 as well. public static DateTime FirstDateOfWeekISO8601(int year, int weekOfYear) {