StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

PO
text
Body
copied!<p>Do we need to consider people who is smaller than 1 year? as Chinese culture, we describe small babies' age as 2 months or 4 weeks. </p> <p>Below is my implementation, it is not as simple as what I imagined, especially to deal with date like 2/28. </p> <pre><code>public static string HowOld(DateTime birthday, DateTime now) { if (now < birthday) throw new ArgumentOutOfRangeException("birthday must be less than now."); TimeSpan diff = now - birthday; int diffDays = (int)diff.TotalDays; if (diffDays > 7)//year, month and week { int age = now.Year - birthday.Year; if (birthday > now.AddYears(-age)) age--; if (age > 0) { return age + (age > 1 ? " years" : " year"); } else {// month and week DateTime d = birthday; int diffMonth = 1; while (d.AddMonths(diffMonth) <= now) { diffMonth++; } age = diffMonth-1; if (age == 1 && d.Day > now.Day) age--; if (age > 0) { return age + (age > 1 ? " months" : " month"); } else { age = diffDays / 7; return age + (age > 1 ? " weeks" : " week"); } } } else if (diffDays > 0) { int age = diffDays; return age + (age > 1 ? " days" : " day"); } else { int age = diffDays; return "just born"; } } </code></pre> <p>This implementation has passed below test cases.</p> <pre><code>[TestMethod] public void TestAge() { string age = HowOld(new DateTime(2011, 1, 1), new DateTime(2012, 11, 30)); Assert.AreEqual("1 year", age); age = HowOld(new DateTime(2011, 11, 30), new DateTime(2012, 11, 30)); Assert.AreEqual("1 year", age); age = HowOld(new DateTime(2001, 1, 1), new DateTime(2012, 11, 30)); Assert.AreEqual("11 years", age); age = HowOld(new DateTime(2012, 1, 1), new DateTime(2012, 11, 30)); Assert.AreEqual("10 months", age); age = HowOld(new DateTime(2011, 12, 1), new DateTime(2012, 11, 30)); Assert.AreEqual("11 months", age); age = HowOld(new DateTime(2012, 10, 1), new DateTime(2012, 11, 30)); Assert.AreEqual("1 month", age); age = HowOld(new DateTime(2008, 2, 28), new DateTime(2009, 2, 28)); Assert.AreEqual("1 year", age); age = HowOld(new DateTime(2008, 3, 28), new DateTime(2009, 2, 28)); Assert.AreEqual("11 months", age); age = HowOld(new DateTime(2008, 3, 28), new DateTime(2009, 3, 28)); Assert.AreEqual("1 year", age); age = HowOld(new DateTime(2009, 1, 28), new DateTime(2009, 2, 28)); Assert.AreEqual("1 month", age); age = HowOld(new DateTime(2009, 2, 1), new DateTime(2009, 3, 1)); Assert.AreEqual("1 month", age); // NOTE. // new DateTime(2008, 1, 31).AddMonths(1) == new DateTime(2009, 2, 28); // new DateTime(2008, 1, 28).AddMonths(1) == new DateTime(2009, 2, 28); age = HowOld(new DateTime(2009, 1, 31), new DateTime(2009, 2, 28)); Assert.AreEqual("4 weeks", age); age = HowOld(new DateTime(2009, 2, 1), new DateTime(2009, 2, 28)); Assert.AreEqual("3 weeks", age); age = HowOld(new DateTime(2009, 2, 1), new DateTime(2009, 3, 1)); Assert.AreEqual("1 month", age); age = HowOld(new DateTime(2012, 11, 5), new DateTime(2012, 11, 30)); Assert.AreEqual("3 weeks", age); age = HowOld(new DateTime(2012, 11, 1), new DateTime(2012, 11, 30)); Assert.AreEqual("4 weeks", age); age = HowOld(new DateTime(2012, 11, 20), new DateTime(2012, 11, 30)); Assert.AreEqual("1 week", age); age = HowOld(new DateTime(2012, 11, 25), new DateTime(2012, 11, 30)); Assert.AreEqual("5 days", age); age = HowOld(new DateTime(2012, 11, 29), new DateTime(2012, 11, 30)); Assert.AreEqual("1 day", age); age = HowOld(new DateTime(2012, 11, 30), new DateTime(2012, 11, 30)); Assert.AreEqual("just born", age); age = HowOld(new DateTime(2000, 2, 29), new DateTime(2009, 2, 28)); Assert.AreEqual("8 years", age); age = HowOld(new DateTime(2000, 2, 29), new DateTime(2009, 3, 1)); Assert.AreEqual("9 years", age); Exception e = null; try { age = HowOld(new DateTime(2012, 12, 1), new DateTime(2012, 11, 30)); } catch (ArgumentOutOfRangeException ex) { e = ex; } Assert.IsTrue(e != null); } </code></pre> <p>Hope it's helpful.</p>

Querying!

Guidance

An individual column

Larger individual text columns get their own page to allow for proper reading.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload