判断字符串是否为纯数字、是否包含中文、是否包含Emoji表情

为NSString 添加一个Category：

.h文件

/**
 * 是否为纯数字
 */
- (BOOL)isNumberString;

/**
 * 判断字符串是否包含中文
 */
- (BOOL)isChinese;

/**
 * 判断字符串是否包含表情符号
 */
- (BOOL)stringContainsEmoji;

.m文件

/**
 * 是否为纯数字
 */
- (BOOL)isNumberString
{
    NSString *regex = @"[0-9]+";
    NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
    
    return [pred evaluateWithObject:self];
}

/**
 * 判断字符串是否包含中文
 */
- (BOOL)isChinese
{
    for(int i = 0; i < [self length]; i++){
        
        int a = [self characterAtIndex:i];
        
        if( a > 0x4e00 && a < 0x9fff) {
            
            return YES;
        }
    }
    
    return NO;
}

/**
 * 判断字符串是否包含表情符号
 */
- (BOOL)stringContainsEmoji
{
    __block BOOL returnValue = NO;
    
    [self enumerateSubstringsInRange:NSMakeRange(0, [self 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;
}