Up Working with EF 6

EF Interception

Last modified on September 30, 2014 14:47

You can use the command and connection interception capabilities of Entity Framework 6 in your DevForce application.


Overview

Entity Framework 6 introduced new interception capabilities "to allow external code to observe and potentially intercept EF operations."  A common use of interception is to add logging and simple profiling of low-level EF actions.  In advanced scenarios you can use it to set connection or command level information, such as SQL Server context_info or application role.

You can use these interception capabilities in any DevForce application using EF 6, regardless of whether the model was written Code First or is EDMX-based.  For n-tier applications, the interception must be done on the EntityServer side of your application. 

Connection interception

To intercept connection-level operations, add a class implementing IDbConnectionInterceptor:

C#
public class EFConnectionInterceptor : System.Data.Entity.Infrastructure.Interception.IDbConnectionInterceptor {
  ...
}

The interface defines a number of interception points for transactions, configuration, and connections. 

You must also register your interceptor for EF to use it:

C#
System.Data.Entity.Infrastructure.Interception.DbInterception.Add(new EFConnectionInterceptor());

Command interception

To intercept command-level operations, you can either add a class implementing IDbCommandInterceptor or sub-class the DbCommandInterceptor to override specific operations.  Each provides before and after interception for queries and non-query commands.

C#
public class EFCommandInterceptor : System.Data.Entity.Infrastructure.Interception.IDbCommandInterceptor {
 ...
}

Be sure to register this interceptor too:

C#
System.Data.Entity.Infrastructure.Interception.DbInterception.Add(new EFCommandInterceptor());


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Created by DevForce on September 30, 2014 14:03

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