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C# Entity Framework Basics Extending Our Entity Data Model Refining a Model Using Data Annotations

Unable to get the Data Annotation for Entity working

I tried to add the annotations for the Title property for the Course entity. But it results in compiler errors. It would be great if someone can identify the compiler issue and suggest how to overcome it.

Course.cs
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace Treehouse.CodeChallenges
{
    public class Course
    {
        public Course()
        {
            Students = new List<CourseStudent>();
        }

        public int Id { get; set; }
        public int TeacherId { get; set; }
        [Required, StringLength(20), Column("Title",TypeName="nvarchar(20)")]
        public string Title { get; set; }
        public string Description { get; set; }
        public int Length { get; set; }

        public Teacher Teacher { get; set; }
        public ICollection<CourseStudent> Students { get; set; }
    }
}

2 Answers

[Required, StringLength(20), Column("Title",TypeName="nvarchar(20)")]

I've never seen an attribute called Column. Maybe it's something new but for this challenge if you remove column and set the StringLength to 200 then it will pass the challenge.

[Required, StringLength(200)]

Ed, that worked! Thanks! This question was throwing me for a loop as well!