How to append unicode ranging U+0000 to U+0099 to NSString in iOS

Question

How to append unicode ranging U+0000 to U+0099 To NSString in iOS. I have used the following link for reference http://en.wikipedia.org/wiki/List_of_Unicode_characters

For a string literal? What have you tried? http://stackoverflow.com/questions/5690172/xcode-utf-8-literals a NUL character is not supported within a string (it indicates the terminator of the string). If, however you're actually trying to construct binary data, then a string is not the correct data type for that — Anya Shenanigans, May 23 '13 at 07:02
What do you mean by "add" them? Append them to an existing string? Or put them into a literal NSString? — borrrden, May 23 '13 at 07:02

Dharmbir Singh · Answer 1 · 2013-05-23T07:13:14.720

Try to use this one....

NSString uses UTF-16 to store codepoints internally, so those in the range you're looking for (U+1F300 to U+1F6FF) will be stored as a surrogate pair (four bytes). Despite its name, characterAtIndex: (and unichar) doesn't know about codepoints and will give you the two bytes that it sees at the index you give it (the 55357 you're seeing is the lead surrogate of the codepoint in UTF-16).

To examine the raw codepoints, you'll want to convert the string/characters into UTF-32 (which encodes them directly). To do this, you have a few options:

1) Get all UTF-16 bytes that make up the codepoint, and use either this algorithm or CFStringGetLongCharacterForSurrogatePair to convert the surrogate pairs to UTF-32.

2) Use either dataUsingEncoding: or getBytes:maxLength:usedLength:encoding:options:range:remainingRange: to convert the NSString to UTF-32, and interpret the raw bytes as a uint32_t.

3) Use a library like ICU.

score 0 · Answer 2 · answered May 23 '13 at 07:47

I'm not sure this is 100% correct solution, but it works:

NSString *uniString = [NSString stringWithFormat:@"%C", (unichar)0x0021];

Where 0x0021 is your unicode char code.

You can test it with this loop:

for (unichar ch = 0x0000; ch <= 0x0099; ch++) {
    NSString *uniString = [NSString stringWithFormat:@"%C", ch];
    NSLog(@"%@", uniString);
}

How to append unicode ranging U+0000 to U+0099 to NSString in iOS

2 Answers2