How to retrieve output parameter from stored procedure by EF code first

To retrieve the data for a stored procedure call, you can use the following

using(var db = new YourConext())
{
       var details = db.Database.SqlQuery<YourType>("exec YourProc @p", 
                      new SqlParameter("@p", YourValue));
}

YourType: might be int or string or long or even a ComplexType

@p: in case if the stored procedure has parameters and you can define as many as you need from parameters

if you need more information about SqlQuery , you might check the following

1. Writing SQL queries for entities
2. Entity Framework Code First and Stored Procedures

Hope this will help you