使用实体代码第一种方法找不到我的数据库 [英] Can't find my Database using Entity Code First Approach

问题描述

 

我刚开始使用Entity Framework，我正在使用代码优先方法。在我的模型中，我有一个产品和产品类别。产品属于类别，类别可以有几种产品。

 

I'm just getting started with Entity Framework, am using the code first approach. In my Models I have a Product and ProductCategories. A product belongs to a categpry and a Category can hav several products.

我的型号是 如下所示：

My Models are  as below:

 public class Product
    {
       
            //Model properties --> Table Name in SQL
            [Key]
            public int ProductId { get; set; }
            public string ProductName { get; set; }
            public int CategoryId { get; set; }
            //Foreign Key -----> To establish relationship btw two tables.
            //FK points to the Primary Key of the table it's refrencing


            // A product belongs to a ----> Category
            public virtual ProductCategory Category { get; set; }

            /*Virtual --> Navigation property.It enables the Lazy Loading feature of EF.
            Lazy --> The content of the property with the "virtual" will be automatically loaded from the Db
            when try to access them.*/
     
    }

public class ProductCategory
    {
            //Model properties --> Table Name in SQL
            [Key] //PK
            public int CategoryId { get; set; }
            public string CategoryName { get; set; }
            // A Category ----> has many products (List of Products)
            public virtual List<Product> Products { get; set; }

            /*Virtual --> Navigation property.It enables the Lazy Loading feature of EF.
            Lazy --> The content of the property with the "virtual" will be automatically loaded from the Db
            when try to access them.*/
     
    }

我的上下文类

class Context: DbContext
    {
        /*make context clas inherit the DbContext System.Data.Entity.DbContext
    and exposes a typed DbSet<TEntity> for each class in our model.*/
        
            public DbSet<Product> products { get; set; }
            public DbSet<ProductCategory> categories { get; set; }

            //products, categories --> are used to access this Entites (Tables) to perform CRUD operations from our GenericDAL

        }

    static void Main(string[] args)
        {
            //instantiate GenericDAL to be able to access our data base and perform CRUD Operation on its Entities (Tables)
            GenericDAL<Product> objPro = new GenericDAL<Product>();
            GenericDAL<ProductCategory> objProCat = new GenericDAL<ProductCategory>();

            Product pro = new Product { ProductName = "Leisure" };
            objPro.Insert(pro);

            Context db = new Context();

           
            foreach ( var p in db.products) { 
            Console.WriteLine(p.ProductName);
            }
            Console.ReadLine();

        }

打印的应用程序：

休闲休闲休闲郎

Leisure Leisure Leisure

但是当我打开我的SQL Server管理器时，我找不到数据库而且我没有收到任何错误。我做错了什么，任何人都可以帮帮忙....谢谢你b $ b

But When I open my SQL Server Manager I can't find the Database and I don't get any error. What am I doing wrong, Could any one help out .... Thanks

推荐答案

嗨！

这些链接非常有用：

• https://stackoverflow.com/questions/27983083/default-physical-location-of-data-base-created-in-entity-framework-codefirst-app
• https://stackoverflow.com/questions/8003588/entity -code-first-where-is-my-db-file-stored
• https://msdn.microsoft.com/en-us/library/jj200620(v = vs.113）.aspx

• https://stackoverflow.com/questions/27983083/default-physical-location-of-data-base-created-in-entity-framework-codefirst-app
• https://stackoverflow.com/questions/8003588/entity-code-first-where-is-my-db-file-stored
• https://msdn.microsoft.com/en-us/library/jj200620(v=vs.113).aspx

希望它有用。

Hope it wil be useful.

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