Entity Framework DbContext dynamic instantiation with custom Connection String

Question

Migrating from ObjectContext to DbContext code-generation, I realized that context class generated (which inherits from DbContext) has no constructor that receives connectionString neither EntityConnection (like ObjectContext child class had).

This is a problem in my application since I need to instantiate my context dynamically from the concrete Type, using a runtime generated connection string.

score 1 · Answer 1 · answered May 02 '13 at 14:55

1

On your class that inherits the DbContext, you should be able to specify the base constructor that takes the connection sting:

public class MyDbContext : DbContext
{
    public MyDbContext(string connString)
        : base(connString)
    {
    }
}

You will have to use the SQLConnection builder though:

SqlConnectionStringBuilder connBuilder= new SqlConnectionStringBuilder(dbConnString);

And use it in your constructor:

MyDbContext dbContext = new MyDbContext(connBuilder.ToString());

answered May 02 '13 at 14:55

ZanderAdam

434
2
13

Hi Ezakiel! That's the more logical way to do it. But I can't modify my class MyDbContext adding that constructor. ObjectContext suited my needs in this providing out of the box constructor with connection string, can't believe this was no considered in DbContext – Tuk May 02 '13 at 15:19
Edited response and added "partial" to the class definiton resolve your issue; now you haven't to edit the generated code – jlsfernandez Jun 26 '13 at 11:12
Isn't it supposed to be generated right out of the box? – Johnny_D Feb 14 '14 at 11:50

score 0 · Answer 2 · answered Jun 25 '13 at 10:39

0

This helped me:

 public MyDatabaseContext():base("name=MyConnectionString")
  {
  }

answered Jun 25 '13 at 10:39

Maxim Eliseev

3,248
4
29
35

Entity Framework DbContext dynamic instantiation with custom Connection String

2 Answers2

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