CoreFoundation打印Unicode字符

Question

I have the current code and it does seem to work except for the fact CFShow doesn't translate the unicode UTF8 encoding of \é to é

#include <CoreFoundation/CoreFoundation.h>

int main()
{

    char *s = "This is a test of unicode support: fiancée\n";
    CFTypeRef cfs = CFStringCreateWithCString(NULL, s, kCFStringEncodingUTF8);
    CFShow(cfs);

}

Output is

This is a test of unicode support: fianc\u00e9e
                                        |____|
                                           > é doesn't output properly.

How do I instruct CFShow that it is unicode? printf handles it fine when it is ac string.

Answer 1

CFShow() is only for debugging. It's deliberately converting non-ASCII to escape codes in order to avoid ambiguity. For example, "é" can be expressed in two ways: as U+00E9 LATIN SMALL LETTER E WITH ACUTE or as U+0065 LATIN SMALL LETTER E followed by U+0301 COMBINING ACUTE ACCENT. If CFShow() were to emit the UTF-8 sequence, your terminal would likely present it as "é" and you wouldn't be able to tell which variant was in the string. That would undermine the usefulness of CFShow() for debugging.

Why do you care what the output of CFShow() so long as it you understand what the content of the string is?

Answer 2

It appears to me that CFShow knows that the string is Unicode, but doesn't know how to format Unicode for the console. I doubt that you can do anything but look for an alternative, perhaps NSLog .