EF6 Database First making Stored Procedure Async

Question

What's the right way to run a EF6 stored procedure (database-first) in async mode?

I read about ToListAsync() but I don't see that available on stored procedure.

Also not sure if there is a different way to call the stored procedure when the actual call returns (#1) an OUT param or a (#2) list of items:

Case #1

 using (DBContext db = new DBContext())
 {
     ObjectParameter result = new ObjectParameter("Result", 
                                  typeof(global::System.Boolean));

     db.Login("email@email.com", "password", result);
 }

Case #2

 using (DBContext db = new DBContext())
 {
     var result = db.Contact_GetList("New York");
 }

Thanks for the help

Answer 1

To map stored procedures and start using it with out writing any initial code, this is how I did it.

1. create a new model with a new connection string that will generate the connection string automatically in the web.config file where the connection string is at (if you use a current connection string it may no work when you test the function for the SP on the model browser).

2. map your table and the stored procedures (you can test the stored procedures in the model browser).

3. create classes that represents the attributes retrieved by each stored procedure e.g if your stored procedure returns three columns A,B,C, then the class must also have these three columns as attribute with the [key()] on top of the column that is going to be the PK

4. now create your controller with the class created and a new DbContext

5. then copy the information in the data context generated for the model and pasted in the new context that you generate when creating the controller.

6. when you want to use the store procedures they will be ready on the db.context because you paste their code on you new db-context that you create when the controller was crated.

NOTE: I hope this is not confusing but I can use the stored procedures with out typing any code, please ask me if you need sample code or screen shots, your new db-context will not over write after you created

This is the stored procedure I map

'--------------------------------------------------------------------------
' <auto-generated>
'     This code was generated from a template.
'
'     Manual changes to this file may cause unexpected behavior in your application.
'     Manual changes to this file will be overwritten if the code is regenerated.
' </auto-generated>
'-----------------------------------------------------------------------

Imports System
Imports System.Collections.Generic

Partial Public Class phone_CurrentConferences_Result
    Public Property AppointmentID As Integer
    Public Property AppTitle As String
    Public Property DateTime As Nullable(Of Date)
    Public Property [Date] As String
    Public Property Time As String
    Public Property Company As String
    Public Property Contact As String
    Public Property Phone As String
    Public Property Office As String
    Public Property Lead_Director As String
    Public Property TBD As Nullable(Of Boolean)
    Public Property conference As String
End Class

This is the same model with a primary key

Imports System
Imports System.Collections.Generic
Imports System.ComponentModel.DataAnnotations

Public Class Conferences
    [Key]
    Public Property AppointmentID As Integer
    Public Property AppTitle As String
    Public Property DateTime As Nullable(Of Date)
    Public Property [Date] As String
    Public Property Time As String
    Public Property Company As String
    Public Property Contact As String
    Public Property Phone As String
    Public Property Office As String
    Public Property Lead_Director As String
    Public Property TBD As Nullable(Of Boolean)
    Public Property conference As String
End Class

This is the context generated by the EF

'--------------------------------------------------------------------------
' <auto-generated>
'     This code was generated from a template.
'
'     Manual changes to this file may cause unexpected behavior in your application.
'     Manual changes to this file will be overwritten if the code is regenerated.
' </auto-generated>
'--------------------------------------------------------------------------

Imports System
Imports System.Data.Entity
Imports System.Data.Entity.Infrastructure
Imports System.Data.Entity.Core.Objects
Imports System.Linq

Partial Public Class DayMasterEntities
    Inherits DbContext

    Public Sub New()
        MyBase.New("name=DayMasterEntities")
    End Sub

    Protected Overrides Sub OnModelCreating(modelBuilder As DbModelBuilder)
        Throw New UnintentionalCodeFirstException()
    End Sub

    Public Overridable Function phone_CurrentConferences(number As String, [date] As Nullable(Of Date)) As ObjectResult(Of phone_CurrentConferences_Result)
        Dim numberParameter As ObjectParameter = If(number IsNot Nothing, New ObjectParameter("number", number), New ObjectParameter("number", GetType(String)))

        Dim dateParameter As ObjectParameter = If([date].HasValue, New ObjectParameter("date", [date]), New ObjectParameter("date", GetType(Date)))

        Return DirectCast(Me, IObjectContextAdapter).ObjectContext.ExecuteFunction(Of phone_CurrentConferences_Result)("phone_CurrentConferences", numberParameter, dateParameter)
    End Function

End Class

SO, when I create the controller I use the model with the <KEY()> and I create my own context that will look like this

Imports System.Data.Entity
Imports System.Data.Entity.Infrastructure
Imports System.Data.Entity.Core.Objects

Namespace Models

    Public Class DayMasterContext
        Inherits DbContext

        ' You can add custom code to this file. Changes will not be overwritten.
        ' 
        ' If you want Entity Framework to drop and regenerate your database
        ' automatically whenever you change your model schema, please use data migrations.
        ' For more information refer to the documentation:
        ' http://msdn.microsoft.com/en-us/data/jj591621.aspx

        Public Sub New()
            MyBase.New("name=DayMasterEntities")
        End Sub

        Protected Overrides Sub OnModelCreating(modelBuilder As DbModelBuilder)
            Throw New UnintentionalCodeFirstException()
        End Sub

        Public Property Conferences As System.Data.Entity.DbSet(Of Conferences)
    End Class
End Namespace

Then I copy the info in the context generated by the EF to my context

Imports System.Data.Entity
Imports System.Data.Entity.Infrastructure
Imports System.Data.Entity.Core.Objects

Namespace Models

    Public Class DayMasterContext
        Inherits DbContext

        ' You can add custom code to this file. Changes will not be overwritten.
        ' 
        ' If you want Entity Framework to drop and regenerate your database
        ' automatically whenever you change your model schema, please use data migrations.
        ' For more information refer to the documentation:
        ' http://msdn.microsoft.com/en-us/data/jj591621.aspx

        Public Sub New()
            MyBase.New("name=DayMasterEntities")
        End Sub

        Protected Overrides Sub OnModelCreating(modelBuilder As DbModelBuilder)
            Throw New UnintentionalCodeFirstException()
        End Sub

        Public Overridable Function phone_CurrentConferences(number As String, [date] As Nullable(Of Date)) As ObjectResult(Of phone_CurrentConferences_Result)
            Dim numberParameter As ObjectParameter = If(number IsNot Nothing, New ObjectParameter("number", number), New ObjectParameter("number", GetType(String)))

            Dim dateParameter As ObjectParameter = If([date].HasValue, New ObjectParameter("date", [date]), New ObjectParameter("date", GetType(Date)))

            Return DirectCast(Me, IObjectContextAdapter).ObjectContext.ExecuteFunction(Of phone_CurrentConferences_Result)("phone_CurrentConferences", numberParameter, dateParameter)
        End Function

        Public Property Conferences As System.Data.Entity.DbSet(Of Conferences)
    End Class
End Namespace

So, now you can use this context to query

entConferences(number As String, [date] As Nullable(Of Date)) As ObjectResult(Of phone_CurrentConferences_Result) 

or to get a DBSet(of conferences)

Here is a controller I have created with this technique

Look where I call my stored procedure

Dim conferences = db.phone_CurrentConferences(phoneNumber, currentDate)

Imports System.Data
Imports System.Data.Entity
Imports System.Data.Entity.Infrastructure
Imports System.Linq
Imports System.Net
Imports System.Net.Http
Imports System.Web.Http
Imports System.Web.Http.Description
Imports BIWEBAPI
Imports BIWEBAPI.Models

Namespace Controllers.DayMasterControllers
    Public Class ConferencesController
        Inherits System.Web.Http.ApiController

        Private db As New DayMasterContext

        ' GET: api/Conferences
        Function GetConferences() As IQueryable(Of Conferences)
            Return db.Conferences
        End Function

        ' GET: api/Conferences/3053742500 
        ''' <summary>
        ''' Use to get the current conferences  selected by date
        ''' </summary>
        ''' <param name="id">phone number and date separated by coma ",""</param>
        ''' <returns>conferences by date</returns>
        ''' <remarks></remarks>
        <ResponseType(GetType(Conferences))>
        Function GetConferences(ByVal id As String) As List(Of Conferences)
            Dim conferencelist = New List(Of Conferences)
            Dim dateAndPhoneNumber = Split(id, ",")
            Dim currentDate = ""
            Dim phoneNumber = dateAndPhoneNumber(0)

            If dateAndPhoneNumber.Length > 1 Then
                currentDate = DateTime.Parse(dateAndPhoneNumber(1))
            Else : currentDate = DateTime.Today
            End If

            Dim conferences = db.phone_CurrentConferences(phoneNumber, currentDate)

            For Each conferenceInQuery As Object In conferences
                Dim conference = New Conferences()
                conference.AppointmentID = conferenceInQuery.AppointmentID
                conference.AppTitle = conferenceInQuery.AppTitle
                conference.DateTime = conferenceInQuery.DateTime
                conference.[Date] = conferenceInQuery.[Date]
                conference.Time = conferenceInQuery.Time
                conference.Company = conferenceInQuery.Company
                conference.Contact = conferenceInQuery.Contact
                conference.Phone = conferenceInQuery.Phone
                conference.Office = conferenceInQuery.Office
                conference.Lead_Director = conferenceInQuery.Lead_Director
                conference.TBD = conferenceInQuery.TBD
                conference.conference = conferenceInQuery.conference

                conferencelist.Add(conference)
            Next

            Return conferencelist
        End Function

        ' PUT: api/Conferences/5
        <ResponseType(GetType(Void))>
        Function PutConferences(ByVal id As Integer, ByVal conferences As Conferences) As IHttpActionResult
            If Not ModelState.IsValid Then
                Return BadRequest(ModelState)
            End If

            If Not id = conferences.AppointmentID Then
                 Return BadRequest()
            End If

            db.Entry(conferences).State = EntityState.Modified

            Try
                db.SaveChanges()
            Catch ex As DbUpdateConcurrencyException
                If Not (ConferencesExists(id)) Then
                    Return NotFound()
                Else
                    Throw
                End If
            End Try

            Return StatusCode(HttpStatusCode.NoContent)
       End Function

       ' POST: api/Conferences
       <ResponseType(GetType(Conferences))>
       Function PostConferences(ByVal conferences As Conferences) As IHttpActionResult
           If Not ModelState.IsValid Then
               Return BadRequest(ModelState)
           End If

           db.Conferences.Add(conferences)
           db.SaveChanges()

           Return CreatedAtRoute("DefaultApi", New With {.id = conferences.AppointmentID}, conferences)
       End Function

       ' DELETE: api/Conferences/5
       <ResponseType(GetType(Conferences))>
       Function DeleteConferences(ByVal id As Integer) As IHttpActionResult
           Dim conferences As Conferences = db.Conferences.Find(id)

           If IsNothing(conferences) Then
               Return NotFound()
           End If

           db.Conferences.Remove(conferences)
           db.SaveChanges()

           Return Ok(conferences)
       End Function

       Protected Overrides Sub Dispose(ByVal disposing As Boolean)
           If (disposing) Then
               db.Dispose()
           End If

           MyBase.Dispose(disposing)
       End Sub

       Private Function ConferencesExists(ByVal id As Integer) As Boolean
           Return db.Conferences.Count(Function(e) e.AppointmentID = id) > 0
       End Function
   End Class

End Namespace

Answer 2

As per this workitem you would need to use SqlQueryAsync. Feel free to upvote the work item on the EF Codeplex site.