Matt Johnson-Pint - Code of Matt

List of 2020 Leap Day Bugs

The following is a list of many bugs caught on or near leap day, February 29th, 2020. Each link below references the issue with supporting details where available.

date-time

On the Life Cycle of a Leap Year Bug

Back in 2016, I wrote about leap year bugs [https://codeofmatt.com/happy-new-leap-year/]. Since another leap year is almost here, I figure it's time to revisit the subject. I've gathered quite a bit of knowledge in this area since then. Hunting down leap year bugs has actually been part of

date-time

Please don't call it Epoch Time

Every so often, I'll come across a StackOverflow question or other Internet posting that says something like: > How do I get the epoch time? Or maybe: > I have an epoch time and I want to get the next day's epoch time. Or even better: > I changed my epoch time to

talks

CodeMash 2017

Today, I had the pleasure of speaking at CodeMash 2017. The slides for my talk, entitled "How to Have the Best Dates Ever!" are available here [https://www.dropbox.com/s/78gcn84zubbcvgz/Best%20Dates%20Ever.pdf?dl=1]. I also recorded the presentation, and you can watch it on YouTube

time-zone

Windows Registry Patch for Egypt 2016 Cancellation of DST

As you may know if you follow my blog, I previously wrote about the recent time zone chaos in Egypt [https://codeofmatt.com/2016/07/01/time-zone-chaos-inevitable-in-egypt/]. In this post I'd like to offer some guidance on what to do about it. On Microsoft Windows desktop or server operating systems,

time-zone

Time Zone Chaos Inevitable in Egypt

I would like to give everyone a heads up about the situation in Egypt. There is likely to be some confusion over the next week or so about what the local time is in Egypt, and it's entirely possible that the computers of the world may be erroneously blamed for

time-zone

On the Timing of Time Zone Changes

What do Turkey, Chile, Russia, Venezuela, Azerbaijan, North Korea and Haiti all have in common? Time Zone Chaos! No, that's not the punchline to a joke. It's actually quite a serious problem. The biggest issue with time zones is not that they exist, nor that they have daylight saving time.

leap-year

List of 2016 Leap Day Bugs

The following is a list of all the bugs caught during leap day, February 29th, 2016. Each link below references the issue with supporting details where available. If you're looking for information of how to avoid leap year bugs, or examples of disastrous leap year bugs from previous years, please

leap-year

Happy New LEAP Year!

If you haven't realized it yet, 2016 is a leap year. For most people, this may just be an interesting oddity. An extra day to work or play. But for developers, the leap year can cause significant pain. It's January 1st as I'm writing this. If you are just now

talks

Cloud Scalability at CodeMash and on Channel 9

I recently spent some time talking with Seth Juarez of Channel 9 about how to design your applications to scale well in the cloud.Check out the video here! [https://channel9.msdn.com/Blogs/Seth-Juarez/Cloud-Scalability-Patterns-with-Matt-Johnson] I'll also be giving a talk on this subject at CodeMash in Ohio, Jan

talks

.NET Rocks!

"Well, Richard..." "Yeah Buddy," "Guess what time it is?" "... I ... Don't ... Know !!!" "It's time to... uh.. to.. Hey, what the hell time is it anyway?!! What's going on!" "I used to know, or I used to think I knew. I just don't know any more!" "I don't know either." MISSION

talks

Seattle Code Camp 2015

I had the privelege of speaking at Seattle Code Camp [http://seattle.codecamp.us] this past weekend. Thanks to everyone that came out to hear me talk about time and time zones, including Noda Time [http://nodatime.org] and Moment.js [http://momentjs.com]. If you missed it, you can

talks

Hanselminutes

I was recently interviewed by Scott Hanselman for his Hanselminutes podcast. If you're interested in time, especially with .NET, I hope you will listen! Check it out in show #485 [http://www.hanselminutes.com/485/the-problem-with-datetime-nodatime-with-matt-johnson] .

JavaScript

JavaScript Date Parsing Changes in ES6

Do you know the difference between these two lines? var d1 = new Date("2015/06/17"); var d2 = new Date("2015-06-17"); How about these? var d1 = new Date("2015/06/17 00:00:00"); var d2 = new Date("2015-06-17 00:00:00"); Or these? var d1 = new Date("2015/06/

.NET

Beware the Edge (cases) of Time!

Ahh, time zones. There are so many wonderful traps to fall into. Consider this bit of code, from a recent blog post by Rick Strahl [http://weblog.west-wind.com/posts/2015/Feb/10/Back-to-Basics-UTC-and-TimeZones-in-NET-Web-Apps] : ///

/// Converts a local machine time to the user's timezone time /// by applying the difference between the

.NET

Five Common Daylight Saving Time Antipatterns of .NET Developers

It's 2015, and Daylight Saving Time is just around the corner. For most of North America, the clocks will "spring-forward" on Sunday, March 8th, stealing an hour of precious time from our daily routine. A few weeks later, the same thing will occur in much of Europe on Sunday, March

time-zone

What is a Time Zone?

Almost any time you call up a friend, relative, or business associate in another part of the world, you'll realize that your time isn't always the same as their time, and the reason is "time zones". You probably know a little about time zones already, but just what exactly is

RavenDB

Working with Date and Time in RavenDB

The following is an article I wrote for the knowledge base on the RavenDB web site [http://ravendb.net/] back in August of 2013. Recently, the site was revamped and the knowledge base was removed. Since the information is still relevant, I thought it would be worth republishing here. Enjoy!

productivity

The Magic F4 Key in Microsoft Office

In the "you learn something new every day" department, I was working in Excel today and had to look up some obscure way to manipulate a pie chart [http://chandoo.org/wp/2009/12/02/group-small-slices-in-pie-charts/]. The resource helped me solve the problem at hand, but also introduced me to

.NET

Localized time zone names in .NET

If you've ever used the TimeZoneInfo class in the .NET framework, you probably know that it has properties intended for display of a time zone to the end user. Specifically, these are the DisplayName, StandardName, and DaylightName properties. However, there are a few problems with these. * Unlike many other items

time-zone

Russia 2014 Time Zone Changes

Are you prepared for Russia's major time zone changes [http://www.timeanddate.com/news/time/russia-abandons-permanent-summer-time.html] ? If you are either in Russia yourself, or interact with Russian customers or users, you will need to ensure your time zone data has been updated before the changes go into effect on

talks

Pluralsight - Date and Time Fundamentals

I'm happy to announce that the video course I've been working on for Pluralsight, "Date and Time Fundamentals" [http://pluralsight.com/training/Courses/TableOfContents/date-time-fundamentals] has finally been released! Here's one of my favorite slides: But seriously - There's a lot of great material in here. Have you ever needed

talks

Seattle Code Camp

I'll be speaking this Saturday at Seattle Code Camp about several issues that time zones can create in your applications. If you are near the Puget Sound area, please come out and see my talk [https://seattle.codecamp.us/Sessions/Details/6422], and many other interesting sessions [https://seattle.codecamp.

time-zone

UTC vs GMT

I'm not going to dive into a history lesson here. This is about practical, usable information in today's modern world. You can always go read more about GMT [http://en.wikipedia.org/wiki/Greenwich_Mean_Time] and UTC [http://en.wikipedia.org/wiki/Coordinated_Universal_Time] on Wikipedia. * What is

time-zone

Egypt goes back to Daylight Saving Time

With only a week's notice, the government of Egypt has decided to go back to daylight saving time - effective today. That's right, it was casually announced [http://english.ahram.org.eg/NewsContent/1/64/100735/Egypt/Politics-/Egypts-government-to-reapply-daylight-saving-time-.aspx] on May 7th, and went into place at Midnight on