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POCan't form some simple POCO's to use with "Code First" Entity Framework, please check for mistake
 

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  1. POCan't form some simple POCO's to use with "Code First" Entity Framework, please check for mistake
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    <p>So I decided to go with the code first/DbContext approach, but already have an existing database file. Nothing complex, so I am thinking I can just create the DbContext derived container class with DbSets for the respective POCO's, create the connection string to my database and I should be set. However I believe I am having difficulties properly declaring the properties in my entity classes since I am getting errors when trying access an object through the navigational properties. Usually telling me <code>Object reference not set to an instance of an object</code> when I try <code>context.Products.Find(1).Category.CATNAME;</code> etc. Also tried declaring the collection properties with virtual keyword to no avail.</p> <p><strong>Some specifics of the database schema are:</strong></p> <blockquote> <p>In Categories table the PCATID is a foreign key to the CategoryID in the same Categories table and can be null.</p> <p>Both CategoryID and RootCategoryID in Products table can be null and are both foreign keys to CategoryID in the Categories table.</p> </blockquote> <p>I am testing things at the moment but will be setting a lot of the fields to non null types eventually.</p> <p><img src="https://i.stack.imgur.com/PW7KM.jpg" alt="enter image description here"></p> <p>Here are my entity POCO's and the entity Dbset container class:</p> <pre><code> public class Category { [Key] public int CategoryID { get; set; } public string CATNAME { get; set; } public int PCATID { get; set; } public ICollection&lt;Category&gt; Categories { get; set; } public ICollection&lt;Product&gt; Products { get; set; } } public class Product { [Key] public int ProductID { get; set; } public int CategoryID { get; set; } public int RootCategoryID { get; set; } public string Name { get; set; } public string ShortDescription { get; set; } public string LongDescription { get; set; } public string Keywords { get; set; } public decimal ListPrice { get; set; } public Category Category { get; set; } } public class EFDbContext: DbContext { public DbSet&lt;Product&gt; Products { get; set; } public DbSet&lt;Category&gt; Categories { get; set; } } </code></pre>
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    1. COCan you post an screenshot with diagram of existing database (from SQL Management Studio for example), and linq-query that you execute?
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      1. USAlexander Molodih
    2. COYes, done.......
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      1. USLaserBeak
 

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