Re: [Boost-users] converting ptime to/from CLR (.NET) DateTime

From: Jeff Garland (jeff_at_[hidden])
Date: 2007-06-02 12:11:35

Jens Schluetter wrote:
> Hi,
>  
> I'm kinda stuck. I'm working on an inter op library to glue C++ code 
> that uses ptime with C# code that uses (of course) the .NET DateTime 
> format. Since the system needs the outmost performance I'm looking for a 
> way to use binary conversion. Conversion from .NET to ptime is easy 
> since there is a from_ftime<> conversion method, however the other 
> direction is somewhat blocked since no ptime to FILE_TIME conversion 
> exists.
 >
> My current workaround is using ISO time strings but performance is 
> somewhat dismal since there is a lot of string <> binary conversion.
> Does anyone know of a more straight forward (binary)way of converting? 
> And just in case, using regular time_t as common denominator is not an 
> option since at leas millisecond resolution is required.
 >
> I'd be greatful for any recommendations/ideas.

Why don't you write a to_ftime function?  You can get all the elements out of 
the ptime to calculate back to a ftime probably as efficiently as the to_ftime 
call.  Of course on the way back to ftime you have to be at least aware that 
ptime can hold values outside the range of ftime (like not_a_date_time, 
infinities, and dates < 1601) -- presumably you would want an exception there.
If you look at date_time/filetime_functions.hpp that should give you some ideas.

Jeff