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c#.netvb.netwindows-mobilecompact-framework

.net - Problems with Array.Sort and Array.BinarySearch - culture and globalization


I need to sort an array containing a list of words and search the same using binarysearch. For certain reasons, the word-list must always be sorted using the sorting-rules of "en-US" i.e. American Regional Settings. The code will run under various international Operating Systems and of course, this will mean that the word-list will be sorted differently according to the local Regional Settings in use. One problem could arise on a computer/device running with Lithuanian Regional Settings. Why? Because the letter "Y" in most languages is sorted like X-Y-Z while in Lithuanian, the sort order is I-Y-J. This behavior would create havoc to my program.

On a desktop-PC, I could change momentarily the Regional Settings into American English by using:

Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture("en-US")

However, since I am developing for Windows Mobile (CF.NET), this piece of code is not possible to implement.

I found some hacks which could let me change the Regional Settings on the device programmatically but they are not "official" and considered risky so I prefer avoiding these.

So my question is: how can I force Array.Sort and Array.BinarySearch to use CultureInfo = "en-US" while sorting and searching regardless of the Regional Settings set on the device?

I believe I could use:

Public Shared Function BinarySearch(Of T) ( _
    array As T(), _
    value As T, _
    comparer As IComparer(Of T) _
) As Integer

and implement Comparer to take into consideration CultureInfo (and set it to "en-US") but I don't know how to do that despite trying hard. If anyone could post some sample-code in VB.Net or C# or an explanation of how to do it, I would be very grateful.

If you are aware of any alternative solution which works in CF.Net, then, of course, I am all ears.

Thanks.

EDIT:

I will consider Twanfosson's answer as the accepted solution since my question clearly stated that I wanted to maintain an association with the English language.

However, in means of flexibility, I believe Guffa's answer is the best one. Why? Let's use another example: In German, the letter Ö is sorted Ö-X-Z while in Swedish and Finnish, the order is X-Z-Ö. In Estonian the sort order is Z-Ö-X. Complicated, isn't it? Guffa's solution will let me force Swedish sorting-order (changing CultureInfo) on a device running under German Regional settings. Using Comparer.DefaultInvariant with its association to English wouldn't help in this case, probably the letter Ö would end up with O. Therefore my vote will go to Guffa.


Solution

  • Is it not possible to use the Invariant culture?

    InvariantCulture retrieves an instance of the invariant culture. It is associated with the English language but not with any country/region.

    Using the invariant culture would make this trivial.

    Array.Sort( myArray, Comparer.DefaultInvariant );
    
    Array.BinarySearch( myArray, myString, Comparer.DefaultInvariant );