On Mar 21, 2013, at 2:34 AM, Jean-Daniel Dupas <devli...@shadowlab.org> wrote:
> > Le 21 mars 2013 à 09:27, Luca Ciciriello <luca_cicirie...@hotmail.com> a > écrit : > >> Hi all. >> I'm using in my iOS project some Objective-C++ modules. Here I have some >> conversion from NSString to C++11 std::string. After this conversion I found >> (correctly) in my std::string some 2-byte characters. >> My question is: How can I count the number of chars and not the numbers of >> byte in my std::string? >> > > Don't use std::string to store unicode string. They are not design to support > such content. > > You can use std::wstring instead. Actually, std::string works *just fine* for UTF-8 strings. It's just that, in Unicode, 1 character doesn't necessarily fit in 1 byte. Also, you can't easily do truncation of strings (you might be truncating the string in the middle of a multi-byte sequence -- which is true in pretty much every encoding except UCS-4). UTF-8 is relatively easy to work with, however. You look at the previous byte in the string to see if your current character is part of a multi-byte sequence or not -- and keep going back until you find one that doesn't have the high-bit set, and that's the last character of the previous sequence. Of course, that "go back" doesn't mean anything if you're already at the first byte in your string... -- Glenn L. Austin, Computer Wizard and Race Car Driver <>< <http://www.austin-soft.com> _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
