使用AutoFac選擇基於實體的DbContext

Question

我試圖根據autofac實體指定要使用哪個dbcontext。下面是我的代碼：

的Global.asax

foreach (var database in DatabaseManager.Databases) 
      { 
       builder.Register<IDbContext>(c => new CodesObjectContext(database.ConnectionString, database.Alias)) //database.Alias is database name 
        .As<IDbContext>() 
        .Named<IDbContext>(database.Alias) 
        .InstancePerLifetimeScope(); 
      } 
builder.RegisterGeneric(typeof(EfRepository<>)).As(typeof(IRepository<>)).InstancePerLifetimeScope(); 

反正我有可以指定的DbContext傳遞給EfRepository？

public partial class EfRepository<T> : IRepository<T> where T : BaseEntity 
    { 
     private readonly IDbContext _context; 
     private IDbSet<T> _entities; 

     public EfRepository(IDbContext context) 
     { 
      this._context = context; 
     } 
} 

，並在我的實體，我將有這樣的事情

[DatabaseName("Database1")] 
public partial class SampleEntity : BaseEntity 
{ 
} 

修訂 這裏是我的ObjectContext類

public class CodesObjectContext : DbContext, IDbContext 
    { 
     public virtual string DatabaseName { get; private set; } 
     public CodesObjectContext(string nameOrConnectionString, string databaseName) 
      : base(nameOrConnectionString) 
     { 
      DatabaseName = databaseName; 
     }    
} 

那麼，有沒有一種方法來匹配實體數據庫屬性和上下文數據庫名稱，然後僅將此上下文傳遞給存儲庫構造器

Answer 1

假設你已經確定你的屬性數據庫名，我會回答

//first in your base context, define contructor that takes string as database name. 
//It should be something like this 
public MyContext(string mydbName = "DefaultDBName") : base(mydbName) 
     { 
     } 

// In your getter, do something like this, get database Name from your attributes 
string dbName = 
      (DatabaseName) Attribute.GetCustomAttribute(typeof(T), typeof (DatabaseName)); 
if(dbName==null) throw new Exception ("Missing Attribute"); 
else 
{ 
// .Name might change depending on your attribute 
string DatabaseName = db.Name; 
// then init your context 
    using (var db = new MyContext(DatabaseName)) 
    {//do something } 
} 

我希望這將有助於。