Code-First MetaData

Question

What should I use as MetaData while I'm using Code-First Approach via EntityConnectionStringBuilder

EntityConnectionStringBuilder entityBuilder;
entityBuilder.MetaData = ??  // Metadata = @"res://*/;";

I got this error :

{"The specified metadata path is not valid. A valid path must be either an existing directory, an existing file with extension '.csdl', '.ssdl', or '.msl', or a URI that identifies an embedded resource."}

• I didn't make any model on this approach, As I thought it isn't needed.

• All I want is to do everything programmatically.

• Everything was working fine in Database-First Approach.

• Here I made the Connection String and passed it to the Context.

• The EF Version is 5.0.

• The database is existed.

• Should I use any thing else to avoid MetaData Checking, such as initializers or ??

Answer 1

For CodeFirst you use just a "regular" connection string - i.e. without metadata. CodeFirst will generate metadata artifacts for you under the cover and will pass them to the ObjectContext instance without any additional action required. You should not use EntityConnectionStringBuilder.

Typically you just derive your context from the DbContext and make a parameterless constructor that calls base and passes the name of the connection string from the config e.g.:

public class MyContext : DbContext
{
    public MyContext() : base("Name=NorthwindConnectionString") {}
}

You can also pass a connection string to the DbContext. If you would like to use a connection string builder you would use the SqlConnectionStringBuilder for this and not the EntityConnectionStringBuilder.