把方法写在了NSString类目中

/**是否为emoji**/
- (BOOL)isContainsEmoji
{
    __block BOOL returnValue = NO;
    [self enumerateSubstringsInRange:NSMakeRange(0, [self length])
                               options:NSStringEnumerationByComposedCharacterSequences
                            usingBlock:^(NSString * _Nullable substring, NSRange substringRange, NSRange enclosingRange, BOOL * _Nonnull stop) {
                                const unichar hs = [substring characterAtIndex:0];
                                // surrogate pair
                                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 <= 0x1f918)
                                        {
                                            returnValue = YES;
                                        }
                                    }
                                }
                                else if (substring.length > 1)
                                {
                                    const unichar ls = [substring characterAtIndex:1];
                                    if (ls == 0x20e3 || ls == 0xFE0F || ls == 0xd83c)
                                    {
                                        returnValue = YES;
                                    }
                                }
                                else
                                {
                                     //non surrogate
                                    //颜文字
                                    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;
 }

/**九宫格输入**/
-(BOOL)isNineKeyBoard
{
    NSString *other = @"➋➌➍➎➏➐➑➒";
    int len = (int)self.length;
    for(int i=0;i<len;i++)
    {
        if(!([other rangeOfString:self].location != NSNotFound))
            return NO;
    }
    return YES;
}

基本使用：

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{
    
    
    if (self.isUserName==1) {
        if ([[[textField textInputMode] primaryLanguage] isEqualToString:@"emoji"] || ![[textField textInputMode] primaryLanguage]) {
            return NO;
        }
        
        if ([string isNineKeyBoard]) {
            return YES;
        }else if ([string isContainsEmoji] ) {
            return NO;
        }
    }
    return YES;
}