问题
I feel incredibly stupid for asking this, but the documentation and Google are giving me no love at all.
I have a Unicode character I want to insert into a string literal in the source code of my iPhone app. I know its hex value. What is the proper escape sequence to use? And for that matter, what obvious source of information am I overlooking that would have told me this?
回答1:
Example:
NSString *stuff = @"The Greek letter Beta looks like this: \u03b2, and the emoji for books looks like this: \U0001F4DA";
回答2:
If you don't want to put it directly in your string you can use a format specifier like this:
[string stringByAppendingFormat:@"%C", 0x2665];
回答3:
A more modern approach:
I'm not sure when this feature was added to the language, but as of 2015, at least, Objective-C string literals can contain any Unicode character. For instance, I mark my log lines with emoji because their distinctive colors are an easier way for me to pick them out:
So, if you have the character and not just the code point, and you want to use it in a static string and not dynamically generate it, this is a great approach, since you instantly know what character you're using just by looking at it.
回答4:
The proper escape sequence would be something along the lines of
wchar_t * str = L"\x0627";
See this question: character constant:\000 \xhh
Edit: Oh, sorry, I missed the iPhone and Objective-C tags. The above is valid for generic C/C++, but I have not worked with iPhone development so your mileage may vary.
回答5:
\ is the escape character in objective c, use it before the letter to be escaped like :
NSString temp = @" hello \"temporary.h\" has been inported";
Here if you print the temp string in textview or logs, you will see " being printed as well because we have used the \ before them which is the escape character
来源：https://stackoverflow.com/questions/833822/how-do-i-escape-a-unicode-character-in-my-objective-c-source-code