How to create and related multiple node to another node - neo4j

Question

Imagine these classes in C#:
public class User
{
public int Id { get; set; }
public string Username { get; set; }
}
public class Post
{
public int Id { get; set; }
public string Text { get; set; }
public string[] HashTags { get; set; }
}
each user can add a post and the relation between them would be the Author, each post could have an array of hash-tags which each of them is going to be a separate node in graph.
when i am going to save each post, I would find the user in grph, create a post node and relate them with a Author Relationship.
the Question is how can I create and relate each hashTag to the post in the same query. (to be inside a transaction).
How could I dynamically add item to query to create it.
the problem is that it could not create node and the relation in one line of create.
Here is what I have tried so far:
var cypherQuery = Db.Instance.Cypher
.Match("(user:User)")
.Where((User user) => user.Username == "XYZ")
.Create("user-[:Author]->(post:Post {newPost})")
.WithParam("newPost", new Post() {Id = 1, Text = "Here is my post about #someHashTag"});
//How to relate this node to the number of hashTags in Post Object???
cypherQuery.ExecuteWithoutResults();
is it good to be in single query or should i divide it in multiple round trips.
I Have tried something with foeach but it seams that the post does not have any value inside the foreach loop:
I have tried something like this:
var cypherCommand = Db.Instance.Cypher
.Match("(user:User)")
.Where((User user) => user.Username == "farvashani")
.Create("user-[:Author]->(post:Post {newPost})")
.WithParam("newPost", "here is my post about #Tag1 and Tag2")
.ForEach(#"(hashtag in {hashTags}|
MERGE post-[:Mentioned]->(hash:HashTag {Text: hashtag}))")
.WithParam("hashTags", new string[] {"Tag1", "Tag2"});
cypherCommand.ExecuteWithoutResults();

Answer 1

In my opinion, i think you have to pre-process the Text property first.
String text = ""Here is my post about #someHashTag""; // For example
List<String> hashTags = new List<String>();
int cnt = 0;
foreach (Match match in Regex.Matches(text, #"(?<!\w)#\w+"))
{
hashTags.Add(match.Value);
}
Then create new instance of Post:
Post newPost = new Post
{
Id = 1,
Text = "Here is my post about #someHashTag",
hashTags = hashTags
};
So, you can use this Cypher:
var cypherCommand = Db.Instance.Cypher
.Match("(user:User)")
.Where((User user) => user.Username == "farvashani")
.Create("user-[:Author]->(post:Post {newPost})")
.WithParam(new {newPost}).ExecuteWithoutResults();
Hope this help.
P/s: Could I ask you a question? Do you think it is better for you to retrieve the separated graph if you use each hashTag as a label of Post? newPost:someHashTag for example?