使用Neo4jClient从Neo4j到C＃对象结构获取分层数据

Question

I have get in to a situation that need to Load a hierarchical object Graph from Neo4j into C# using neo4jClient

I have a post Class in C# as fallow:

public class Post : BaseNode
{
    public Post Parent { get; set; }
    public float Id { get; set; }
    public string Text { get; set; }
    public ICollection<HashTag> HashTags { get; set; }
    public ICollection<IKeyCommand> KeyTags { get; set; }
    public ICollection<NeoDateTime> DueDates { get; set; }
    public IdentityUser Author { get; set; }
    public ICollection<IdentityUser> MentionedUsers { get; set; }
    public ICollection<Team> MentionedTeam { get; set; }
    public ICollection<PostAttachment> Attachments { get; set; }
    public string Priority { get; set; }

}

and Here is my Graph :

Now Imagin a method wich need to load all the parent of a graph with all its related properties using parent Id

I have Came up with this C# Code which Produce needed Cypher :

public IList<Post> LoadParents(int id)
    {
        var matchStringTemplate = "(post:Post {{Id:{0}}})-[r:HAS_Parent*]->(parents:Post)";
        var matchString = string.Format(matchStringTemplate, id);

        var q = new CypherFluentQuery(_graphClient) as ICypherFluentQuery;
        q = q.Match(string.Format(matchStringTemplate, id));

        q = q.OptionalMatch("(post:Post)-[mentionedUsersRelation:HAS_MentionedUsers]->(allAssignees:User)");
        q = q.OptionalMatch("(post:Post)-[authorRelation:HAS_Author]->(author:User)");
        q = q.OptionalMatch("(post:Post)-[hashtagRElation:HAS_HashTags]->(hashtags:HashTag)");
        q = q.OptionalMatch("(post:Post)-[HasAttachmentRelation:HAS_Attachments]->(attachment:PostAttachment)");

        q = q.OptionalMatch("(parents:Post)-[pmentionedUsersRelation:HAS_MentionedUsers]->(pallAssignees:User)");
        q = q.OptionalMatch("(parents:Post)-[pauthorRelation:HAS_Author]->(pauthor:User)");
        q = q.OptionalMatch("(parents:Post)-[phashtagRElation:HAS_HashTags]->(phashtags:HashTag)");
        q = q.OptionalMatch("(parents:Post)-[pHasAttachmentRelation:HAS_Attachments]->(pattachment:PostAttachment)");

        var rq = q.Return((post, parents,  allAssignees, author, hashtags, attachment,

            pallAssignees, pauthor, phashtags, pattachment) => new
        {
            Post = post.As<Post>(),
            Parent = parents.As<Post>(),
            Author = author.As<IdentityUser>(),
            MentionedUsers = allAssignees.CollectAsDistinct<IdentityUser>(),
            Attachments = attachment.CollectAsDistinct<PostAttachment>(),
            HashTags = hashtags.CollectAsDistinct<HashTag>()
        })
        .OrderByDescending("post.CreationDate");

        var result = rq.Results;
        var results = result.Select(p => new Post()
        {
            Id = p.Post.Id,

            Text = p.Post.Text,
            CreationDate = p.Post.CreationDate,
            Author = p.Author,
            MentionedUsers = p.MentionedUsers.Select(m => m.Data).ToArray(),
            HashTags = p.HashTags.Select(h => h.Data).ToArray(),
            Attachments = p.Attachments.Select(a => a.Data).ToArray()
        });
        return results.ToList();
    }

the Cypher would be something like this:

 MATCH (post:Post {Id:9601})-[r:HAS_Parent*]->(parents:Post)

OPTIONAL MATCH (post:Post)-[mentionedUsersRelation:HAS_MentionedUsers]->(allAssignees:User)
OPTIONAL MATCH (post:Post)-[authorRelation:HAS_Author]->(author:User)
OPTIONAL MATCH (post:Post)-[hashtagRElation:HAS_HashTags]->(hashtags:HashTag)
OPTIONAL MATCH (post:Post)-[HasAttachmentRelation:HAS_Attachments]->(attachment:PostAttachment)
OPTIONAL MATCH (parents:Post)-[pmentionedUsersRelation:HAS_MentionedUsers]->(pallAssignees:User)

OPTIONAL MATCH (parents:Post)-[pauthorRelation:HAS_Author]->(pauthor:User)
OPTIONAL MATCH (parents:Post)-[phashtagRElation:HAS_HashTags]->(phashtags:HashTag)
OPTIONAL MATCH (parents:Post)-[pHasAttachmentRelation:HAS_Attachments]->(pattachment:PostAttachment)
RETURN post AS Post, collect(distinct parents) AS Parent, author AS Author, collect(distinct allAssignees) AS MentionedUsers, collect(distinct attachment) AS Attachments, collect(distinct hashtags) AS HashTags
ORDER BY post.CreationDate DESC

But the problem is I dont kow how to load the result into the hierarchy strutuer of node and its parent in the post C# class.

the cypher result is what i am looking for when I test the query on db. but everything get messed up in C# object.

here is the query result in neo4jDB:

Answer 1

If your Post class has multiple parents posts, then I think you should change

public Post Parent { get; set; }

to something like

public IEnumerable<Post> Parent { get; set; }

Then you can map all parent nodes in cypher result to this property