Public class is inaccessible due to protection level; Constructor is public

Question

I have a class that is public, ArticleDao, but when I try to use it in another file, it says "ArticleDao is inaccessible due to its protection level." Here is the entire class:

class ArticleDao : IArticleDao
{
    private readonly ContentManager _contentManager;

    private static readonly char[] DelimiterChars = { '|', '\n' };

    private const int ArticlePagingSize = 500;

    public ArticleDao()
    {
        _contentManager = new ContentManager();
    }

    private Image GetImage(XElement element)
    {
        var image = new Image();

        if (String.IsNullOrEmpty((String)element))
        {
            return image;
        }

        XElement imageElement = element.Element("img");
        if (imageElement != null)
        {
            image.Url = (String)imageElement.Attribute("src");
        }
        return image;
    }

    private Link GetLink(XElement element)
    {
        var link = new Link();

        if (String.IsNullOrEmpty((String)element))
        {
            return link;
        }

        XElement anchorElement = element.Element("a");
        if (anchorElement != null)
        {
            link.Url = (String)anchorElement.Attribute("href");
            link.Text = (String)anchorElement;
        }
        return link;
    }

    public Article GetArticle(long id, string html)
    {
        var a = new Article();
        long testid = 556;
        if (id == testid)
        {
            var x = 1;
        }

        XDocument xdoc = XDocument.Parse(html);
        var xElement = xdoc.Element("root");
        if (xElement != null)
        {
            XElement articleElem = xElement.Element("Event");
            if (articleElem != null)
            {
                a = new Article();
                a.Id = id.ToString(CultureInfo.InvariantCulture);
                a.Title = (String)articleElem.Element("Title");
                a.PublishedDate = GetDateTime((String)articleElem.Element("PublishedDate"));
                a.SubHeader = (String)articleElem.Element("SubHeader");
                a.Image = GetImage(articleElem.Element("Image"));
                a.Caption = (String)articleElem.Element("Caption");
                a.Body = (String)articleElem.Element("Body");
                a.Url = GetLink(articleElem.Element("Url"));

            }
        }

        return a;

    }

    public Article GetArticle(Int64 ektronContentId)
    {
        var item = _contentManager.GetItem(ektronContentId);
        return GetArticle(ektronContentId, item.Html);
    }

    public IEnumerable<Article> GetArticles(Int64 folderId)
    {
        int count;
        IEnumerable<Article> articles = new List<Article>(ArticlePagingSize);
        do
        {
            var criteria = new ContentCriteria();
            criteria.AddFilter(ContentProperty.FolderId, CriteriaFilterOperator.EqualTo, folderId);
            criteria.PagingInfo.RecordsPerPage = ArticlePagingSize;

            var articleContentData = _contentManager.GetList(criteria);
            count = articleContentData == null ? 0 : articleContentData.Count;

            articles = articles.Concat(_contentManager.GetList(criteria)
                .Select(i => GetArticle(i.Id, i.Html)));
        } while (count == ArticlePagingSize);
        return articles;
    }

    private DateTime GetDateTime(string date)
    {
        DateTime dt;

        DateTime.TryParse(date, out dt);

        return dt;
    }
}

The constructor is public. I even tried replacing all instances of "private" with "public," but it still says that it is inaccessible. This is the line where I'm trying to invoke it:

private static IArticleDao _articleDao;
public static IArticleDao ArticleDao
{
    get { return _articleDao ?? (_articleDao = new ArticleDao()); }
}

Where it says "_articleDao = new ArticleDao()" is where the error is.

I'm especially confused because to create ArticleDao and IArticleDao, I essentially just copied EventDao and IEventDao and replaced "Event" with "Article." This works:

private static IEventDao _eventDao;
public static IEventDao EventDao
{
    get { return _eventDao ?? (_eventDao = new EventDao()); }
}

but ArticleDao does not work.

Answer 1

You class ArticleDao is a internal, as if you don't specify any accessibility modifier, the default in C# is internal. To resolve this issue you may think of declaring it public

public class ArticleDao : IArticleDao
{
   ...
}