How to create breadcrumbs using Dynamic Data/LINQTOSQL framework?

Question

I need some EXAMPLES or IDEAS on how to created dynamic breadcrumb control which will dynamically generated breadcrumbs for Dynamic Date framework powered by LINQTOSQL

Answer 1

You'll probably need three things:

1. A hierarchy structure in your database*
2. A custom SiteMap provider based on the StaticSiteMapProvider to read the hierarchy
3. A SiteMapPath control to display the Breadcrumb.

* I'd done some hunting around when I wanted something similar for a client site, and decided that storing the path structure in the database would be simplest - I've given the answer previously here for an arbitrary depth site map - note that if you're using SQL2008 you can use the new HierarchyId data type to make this a bit easier.

That being said, if you've got things like categories and products, you can probably get away with a simpler system in your database.

The key functions I needed to create to resolve this were things like:

/// <summary>
/// Gets this SiteMaps children.
/// </summary>
/// <value>The children.</value>
public List<SiteMap> Children {
  get {
    if (null == m_Children && !m_AttemptedToLoadChildren) {
      m_AttemptedToLoadChildren = true;

      m_Children = ctx.GetSiteMapChildrenByPath(_Path, 1).ToList();

      // Sorts ascending.
      m_Children.Sort(( sm1, sm2 ) => sm1.SortOrder.CompareTo(sm2.SortOrder));
      // CMS Sorts Descending, so reverse the list.
      m_Children.Reverse();
    }

    return m_Children;
  }
}

/// <summary>
/// Gets a value indicating whether this instance has any children.
/// </summary>
/// <value>
///  <c>true</c> if this instance has children; otherwise, <c>false</c>.
/// </value>
public bool HasChildren {
  get {
    if (null != Children && Children.Any()) {
      m_HasChildren = true;
    }

    return m_HasChildren;
  }
}

/// <summary>
/// Gets this SiteMaps parent.
/// </summary>
/// <value>The parent.</value>
public SiteMap Parent {
  get {
    if (null == m_Parent && null != _ParentId) {
      m_Parent = ctx.GetSiteMap(_ParentId);
    }

    return m_Parent;
  }
}

GetSiteMap and GetSiteMapChildrenByPath call into stored procs to build the hierarchy as pulling it out with LINQ was going to be quite complex.