//需要检测的字符串
NSString *string = @"你好";
CFStringRef langCStr = CFStringTokenizerCopyBestStringLanguage((CFStringRef)string, CFRangeMake(0, string.length));
//强转为NSString
NSString *languageStr = (__bridge NSString *)langCStr;

//获取当前系统语言
+(NSString *)getCurrentLanguage{
    NSArray *languages = [NSLocale preferredLanguages];
    if(languages == nil){
        return nil;
    }else{
        if([languages count] == 0){
             return nil;
        }else{
             NSString *currentLanguage = [languages objectAtIndex:0];
            //    NSLog(@"%@",currentLanguage);
            return currentLanguage;
        }
    }
}