LinqToEntitiesDomainService.ObjectContext 속성

이 LinqToEntitiesDomainService에 대한 ObjectContext를 가져옵니다.

네임스페이스: System.ServiceModel.DomainServices.EntityFramework
어셈블리: system.servicemodel.domainservices.entityframework.dll의 System.ServiceModel.DomainServices.EntityFramework

사용법

‘사용 방법
Dim value As TContext

value = Me.ObjectContext

구문

‘선언
Protected Friend ReadOnly Property ObjectContext As TContext

protected internal TContext ObjectContext { get; }

protected public:
property TContext ObjectContext {
    TContext get ();
}

/** @property */
protected TContext get_ObjectContext ()

protected internal function get ObjectContext () : TContext

속성 값

이 LinqToEntitiesDomainService에 대한 ObjectContext입니다.

예제

다음 예제에서는 LinqToEntitiesDomainService에서 파생된 도메인 서비스를 보여 줍니다. 데이터를 쿼리, 업데이트 및 삭제하는 메서드가 포함되어 있습니다.

<EnableClientAccess()>  _
Public Class OrderDomainService
    Inherits LinqToEntitiesDomainService(Of AdventureWorksLT_DataEntities)

    Public Function GetSalesOrders() As IQueryable(Of SalesOrderHeader)
        Return Me.ObjectContext.SalesOrderHeaders.Include("SalesOrderDetails")
    End Function
    
    Public Sub UpdateSalesOrder(ByVal currentSalesOrderHeader As SalesOrderHeader)
        Dim originalOrder As SalesOrderHeader = Me.ChangeSet.GetOriginal(currentSalesOrderHeader)

        If (currentSalesOrderHeader.EntityState = EntityState.Detached) Then
            If (IsNothing(originalOrder)) Then
                Me.ObjectContext.Attach(currentSalesOrderHeader)
            Else
                Me.ObjectContext.AttachAsModified(currentSalesOrderHeader, Me.ChangeSet.GetOriginal(currentSalesOrderHeader))
            End If
        End If

        For Each detail As SalesOrderDetail In Me.ChangeSet.GetAssociatedChanges(currentSalesOrderHeader, Function(o) o.SalesOrderDetails)
            Dim op As ChangeOperation = Me.ChangeSet.GetChangeOperation(detail)

            Select Case op
                Case ChangeOperation.Insert
                    If ((detail.EntityState = EntityState.Added) _
                    = False) Then
                        If ((detail.EntityState = EntityState.Detached) _
                                    = False) Then
                            Me.ObjectContext.ObjectStateManager.ChangeObjectState(detail, EntityState.Added)
                        Else
                            Me.ObjectContext.AddToSalesOrderDetails(detail)
                        End If
                    End If
                Case ChangeOperation.Update
                    Me.ObjectContext.AttachAsModified(detail, Me.ChangeSet.GetOriginal(detail))
                Case ChangeOperation.Delete
                    If (detail.EntityState = EntityState.Detached) Then
                        Me.ObjectContext.Attach(detail)
                    End If
                    Me.ObjectContext.DeleteObject(detail)
            End Select
        Next
    End Sub
    
    Public Sub DeleteSalesOrder(ByVal salesOrderHeader As SalesOrderHeader)
        If (salesOrderHeader.EntityState = EntityState.Detached) Then
            Me.ObjectContext.Attach(salesOrderHeader)
        End If

        Select Case salesOrderHeader.Status
            Case 1 ' in process
                Me.ObjectContext.DeleteObject(salesOrderHeader)
            Case 2, 3, 4 ' approved, backordered, rejected
                salesOrderHeader.Status = 6
            Case 5 ' shipped
                Throw New ValidationException("The order has been shipped and cannot be deleted.")
        End Select

    End Sub
End Class

[EnableClientAccess()]
public class OrderDomainService : LinqToEntitiesDomainService<AdventureWorksLT_DataEntities>
{
    public IQueryable<SalesOrderHeader> GetSalesOrders()
    {
        return this.ObjectContext.SalesOrderHeaders.Include("SalesOrderDetails");
    }

    public void UpdateSalesOrder(SalesOrderHeader currentSalesOrderHeader)
    {
        SalesOrderHeader originalOrder = this.ChangeSet.GetOriginal(currentSalesOrderHeader);

        if ((currentSalesOrderHeader.EntityState == EntityState.Detached))
        {
            if (originalOrder != null)
            {
                this.ObjectContext.AttachAsModified(currentSalesOrderHeader, this.ChangeSet.GetOriginal(currentSalesOrderHeader));
            }
            else
            {
                this.ObjectContext.Attach(currentSalesOrderHeader);
            }
        }

        foreach (SalesOrderDetail detail in this.ChangeSet.GetAssociatedChanges(currentSalesOrderHeader, o => o.SalesOrderDetails))
        {
            ChangeOperation op = this.ChangeSet.GetChangeOperation(detail);
            switch (op)
            {
                case ChangeOperation.Insert:
                    if ((detail.EntityState != EntityState.Added))
                    {
                        if ((detail.EntityState != EntityState.Detached))
                        {
                            this.ObjectContext.ObjectStateManager.ChangeObjectState(detail, EntityState.Added);
                        }
                        else
                        {
                            this.ObjectContext.AddToSalesOrderDetails(detail);
                        }
                    }
                    break;
                case ChangeOperation.Update:
                    this.ObjectContext.AttachAsModified(detail, this.ChangeSet.GetOriginal(detail));
                    break;
                case ChangeOperation.Delete:
                    if (detail.EntityState == EntityState.Detached)
                    {
                        this.ObjectContext.Attach(detail);
                    }
                    this.ObjectContext.DeleteObject(detail);
                    break;
                case ChangeOperation.None:
                    break;
                default:
                    break;
            }
        }
    }

    public void DeleteSalesOrder(SalesOrderHeader salesOrderHeader)
    {
        if ((salesOrderHeader.EntityState == EntityState.Detached))
        {
            this.ObjectContext.Attach(salesOrderHeader);
        }
        
        switch (salesOrderHeader.Status)
        {
            case 1: // in process
                this.ObjectContext.DeleteObject(salesOrderHeader);
                break;
            case 2: // approved
            case 3: // backordered
            case 4: // rejected
                salesOrderHeader.Status = 6;
                break;
            case 5: // shipped
                throw new ValidationException("The order has been shipped and cannot be deleted.");
            default:
                break;
        }
       
    }
}

설명

ObjectContext 속성이 null인 경우 CreateObjectContext 메서드가 호출되고 새 ObjectContext가 반환됩니다. ObjectContext 속성을 사용하여 엔터티 데이터 개체와 상호 작용합니다.

스레드 보안

이 형식의 모든 public static(Visual Basic의 경우 Shared) 멤버는 스레드로부터 안전합니다. 모든 인스턴스 멤버는 스레드로부터 안전하지 않을 수 있습니다.

플랫폼

개발 플랫폼

Windows XP Home Edition, Windows XP Professional, Windows Server 2003 , Windows Server 2008 및 Windows 2000

대상 플랫폼

Change History

참고 항목

참조

LinqToEntitiesDomainService 제네릭 클래스
LinqToEntitiesDomainService 멤버
System.ServiceModel.DomainServices.EntityFramework 네임스페이스