判断用户输入中是否含有表情

@implementation NSString (Emoji)

+ (BOOL)stringContainsEmoji:(NSString *)string
{
    __block BOOL returnValue = NO;

    [string enumerateSubstringsInRange:NSMakeRange(0, [string length]) 
    options:NSStringEnumerationByComposedCharacterSequences 
    usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
        const unichar hs = [substring characterAtIndex:0];
        if (0xd800 <= hs && hs <= 0xdbff) {
            if (substring.length > 1) {
                const unichar ls = [substring characterAtIndex:1];
                const int uc = ((hs - 0xd800) * 0x400) + (ls - 0xdc00) + 0x10000;
                if (0x1d000 <= uc && uc <= 0x1f77f) {
                    returnValue = YES;
                }
            }
        } else if (substring.length > 1) {
            const unichar ls = [substring characterAtIndex:1];
            if (ls == 0x20e3) {
                returnValue = YES;
            }
        } else {
            if (0x2100 <= hs && hs <= 0x27ff) {
                returnValue = YES;
            } else if (0x2B05 <= hs && hs <= 0x2b07) {
                returnValue = YES;
            } else if (0x2934 <= hs && hs <= 0x2935) {
                returnValue = YES;
            } else if (0x3297 <= hs && hs <= 0x3299) {
                returnValue = YES;
            } else if (hs == 0xa9 || hs == 0xae || hs == 0x303d || hs == 0x3030 || hs == 0x2b55 || hs == 0x2b1c || hs == 0x2b1b || hs == 0x2b50) {
                returnValue = YES;
            }
        }
    }];

    return returnValue;
}