Question

I have a code that looks like code below in a PC which runs fine:

DateTime.Parse("10/10/2012");

I copied it over to other machine and it says something blaming the date conversion is wrong.
What I had to do to work around it is to use:

DateTime.TryParseExact("10/10/2012", "dd/MM/yyyy", null);

Does anyone know if there is any configuration in c# or the machine that control this such things? (or it might be .net version different between the two computers? but i am pretty sure they are the same in both machine as I used Ms Visual Studio 2008 for both machine).

I am talking about global configuration on windows itself that makes some strict exceptions to my programs. Anyone knows about this?

Answer 1

(You’re mixing ParseExact and TryParseExact.)

The differences come from the CultureInfo.CurrentCulture.Different parts of the world write dates in different ways.

Even saying ParseExact("10/10/2012", "dd/MM/yyyy", null) can be problematic. Have you tried first setting

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("da-DK");

and then doing the above ParseExact? It will fail because the DateSeparator is not "/" in this culture. To fix it, either say

DateTime.ParseExact("10/10/2012", @"dd\/MM\/yyyy", null)

or say

DateTime.ParseExact("10/10/2012", "dd/MM/yyyy", CultureInfo.InvariantCulture)

The first works by “escaping” the slash / so it becomes a literal slash and is not translated to the current DateSeparator. The second one works by giving the invariant culture where we know that the DateSeparator is indeed "/".

Addition:

If you never set CurrentCulture in your code, its value depends on the Regional and language settings of your operating system. I suppose you’re running Windows? Details might depend on exact Windows version.