Does not contain a definition for 'AddToPosts' and no extension method - asp.net-mvc

Question

I am still learning ASP.NET/MVC and following along a tutorial by Matt Blagden (You Tube) on building a Blog..
After making the Post Controller I am getting an error in a snippet of code that handles adding a Tag to a Post if it is a new Post. My thought is the method AddToPosts should have been generated when I added a new Entity Data Model.
The error is:
blog.Models.BlogModel does not contain a definition for 'AddToPosts' and no extension method 'AddToPosts'. PostsController.cs accepting a first argument of type 'blog.Models.BlogModel' could be found (are you missing a using directive or an assembly reference?)
The portion of code that is giving me the error is:
if (!id.HasValue)
{
model.AddToPosts(post);
}
Here is the entire Post Controller
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using blog.Models;
using System.Data.EntityModel;
using System.Text;
namespace blog.Controllers
{
public class PostsController : Controller
{
// Access Model
private BlogModel model = new BlogModel();
public ActionResult Index()
{
return View();
}
// A way to input sample data into database
[ValidateInput(false)]
public ActionResult Update(int? id, string title, string body, etc.....)
{
//IF not an admin redirect back to index
if (!IsAdmin)
{
return RedirectToAction("Index");
}
// Get Post
Post post = GetPost(id);
// Populate simple properties
post.Title = title;
post.Body = body;
post.DateTime = dateTime;
post.Tags.Clear(); // first clear tag list
//ensure input sequence of tag names is not null
tags = tags ?? string.Empty;
//Split the sequence into a list of tag names
string[] tagNames = tags.Split(new char[] { ' ' }, etc...
//Get or create each tag that was named
foreach (string tagName in tagNames)
{
//Add the tag
post.Tags.Add(GetTag(tagName));
}
if (!id.HasValue)
{
model.AddToPosts(post);
}
model.SaveChanges();
return RedirectToAction("Details", new { id = post.ID });
}
// PROMPTS USER TO INPUT DATA FOR DATABASE
public ActionResult Edit(int? id)
{
Post post = GetPost(id);
//ACCUMULATES LIST OF CURRENT TAGNAMES
StringBuilder tagList = new StringBuilder();
foreach (Tag tag in post.Tags)
{
//Append each tagname
tagList.AppendFormat("{0} ", tag.Name);
}
//Gives the tagList to the view
ViewBag.Tags = tagList.ToString();
return View(post);
}
private Tag GetTag(string tagName)
{ // if tag is set then Get the Tag, if not create a new one (Just like GetPost)
return model.Tags.Where(x => x.Name == tagName).FirstOrDefault() ?? etc....
}
private Post GetPost(int? id)
{
// IF id is set then Get the Post, if not make a new one..
return id.HasValue ? model.Posts.Where(x => x.ID == id).First() : etc.....
// TODO: don't just return true
public bool IsAdmin
/* READS SESSION STATE */
{
get { return true; /*{ return Session["IsAdmin"] != null && etc...
}
}
}

Answer 1

If "AddToPosts" coming from static class, try adding using statement of namespace where the Add post class exists.