如何让 Entity Framework Code First 使用 SQL Azure DB？

Question

I'm start to learn EF now. What I want to do is use EF code first create new tables in SQL Azure.

Here is my code:

namespace WebApplication2
{
   public class Blog
   {
       public int UserName { get; set; }
       public int ID { get; set; }
   }

   public class BlogContext : DbContext
   {
       public DbSet<Blog> Blogs { get; set; }

       public BlogContext() : base("MYEF")
       {
       }
   }
}

Code behind:

 protected void Page_Load(object sender, EventArgs e)
 {
        using (var db = new BlogContext())
        {
            var blog = new Blog { UserName = 456 };
            db.Blogs.Add(blog);
            db.SaveChanges();
        }
    }

Web.config :

<connectionStrings>
    <add name="TestDBContext" 
         connectionString="Server=tcp:mydb.database.windows.net,1433;Database=MYEF;User ID=[Username];Password=[MyPassword];Trusted_Connection=False;Encrypt=True;PersistSecurityInfo=True" 
         providerName="System.Data.SqlClient" />
</connectionStrings>

When I check my SQL Azure DB, no table has been created, EF still create the table MYEF in the default SQL Server Express database.

Has anyone done this successfully?

Answer 1

You should pass the connection string name to the base constructor of your BlogContext like this

public BlogContext()
    : base("TestDBContext")
{
}

http://msdn.microsoft.com/en-us/library/gg679467(v=vs.103).aspx

Answer 2

EntityFramework tries to infer the name of the ConnectionString in the web/app.config file from the name of the class which inherits DbContext. In your case, this is BlogContext.

If you simply changed

<connectionStrings><add name="TestDBContext"

to

<connectionStrings><add name="BlogContext" 

then you could do public BlogContext() without passing a hard string to the base class.