Gewusst wie: Anpassen von Feeds mit dem Reflektionsanbieter (WCF Data Services)
WCF Data Services ermöglicht es Ihnen, die Atom-Serialisierung in einer Datendienstantwort anzupassen, damit Eigenschaften einer Entität nicht verwendeten Elementen zugeordnet werden können, die im AtomPub-Protokoll definiert werden. In diesem Thema wird erläutert, wie Zuordnungsattribute für die Entitätstypen in einem Datenmodell definiert werden, das mit dem Reflektionsanbieter definiert wird. Weitere Informationen finden Sie unter Feedanpassung (WCF Data Services).
Das Datenmodell für dieses Beispiel wird im Thema Gewusst wie: Erstellen eines Datendiensts mithilfe des Reflektionsanbieters (WCF Data Services) definiert.
Beispiel
Im folgenden Beispiel werden vorhandenen Atom-Elementen beide Eigenschaften des Order-Typs zugeordnet. Einem benutzerdefinierten Feedattribut wird in einem separaten Namespace die Product-Eigenschaft des Item-Typs zugeordnet.
Imports System
Imports System.Collections.Generic
Imports System.Data.Services
Imports System.Data.Services.Common
Imports System.Linq
Namespace CustomDataService
<EntityPropertyMappingAttribute("Customer", _
SyndicationItemProperty.AuthorName, _
SyndicationTextContentKind.Plaintext, True)> _
<EntityPropertyMapping("OrderId", _
SyndicationItemProperty.Title, _
SyndicationTextContentKind.Plaintext, False)> _
<DataServiceKeyAttribute("OrderId")> _
Public Class Order
Private _orderId As Integer
Private _customer As String
Private _items As IList(Of Item)
Public Property OrderId() As Integer
Get
Return _orderId
End Get
Set(ByVal value As Integer)
_orderId = value
End Set
End Property
Public Property Customer() As String
Get
Return _customer
End Get
Set(ByVal value As String)
_customer = value
End Set
End Property
Public Property Items() As IList(Of Item)
Get
Return _items
End Get
Set(ByVal value As IList(Of Item))
_items = value
End Set
End Property
End Class
<EntityPropertyMappingAttribute("Product", _
SyndicationItemProperty.CategoryTerm, _
true, SyndicationCriteria.CategoryScheme, _
"http://northwindtraders.com/Products")> _
<EntityPropertyMappingAttribute("Url", _
SyndicationItemProperty.LinkHref, false, _
SyndicationCriteria.LinkRel, _
"http://northwindtraders.com/ProductUrl")>
<DataServiceKeyAttribute("Product")> _
Public Class Item
Private _product As String
Private _quantity As Integer
Private _url As String
Public Property Product() As String
Get
Return _product
End Get
Set(ByVal value As String)
_product = value
End Set
End Property
Public Property Quantity() As Integer
Get
Return _quantity
End Get
Set(ByVal value As Integer)
_quantity = value
End Set
End Property
Public Property Url As String
Get
Return _url
End Get
Set(ByVal value As String)
_url = value
End Set
End Property
End Class
Partial Public Class OrderItemData
#Region "Populate Service Data"
Shared _orders As IList(Of Order)
Shared _items As IList(Of Item)
Sub New()
_orders = New Order() { _
New Order() With {.OrderId = 0, .Customer = "Peter Franken", .Items = New List(Of Item)()}, _
New Order() With {.OrderId = 1, .Customer = "Ana Trujillo", .Items = New List(Of Item)()}}
_items = New Item() { _
New Item() With {.Product = "Chai", .Quantity = 10, _
.Url = "http://northwindtraders.com/Teas"}, _
New Item() With {.Product = "Chang", .Quantity = 25, _
.Url = "http://northwindtraders.com/Specialty"}, _
New Item() With {.Product = "Aniseed Syrup", .Quantity = 5, _
.Url = "http://northwindtraders.com/Specialty"}, _
New Item() With {.Product = "Chef Anton's Cajun Seasoning", _
.Quantity = 30, .Url = "http://northwindtraders.com/Spices"}}
_orders(0).Items.Add(_items(0))
_orders(0).Items.Add(_items(1))
_orders(1).Items.Add(_items(2))
_orders(1).Items.Add(_items(3))
End Sub
#End Region
Public ReadOnly Property Orders() As IQueryable(Of Order)
Get
Return _orders.AsQueryable()
End Get
End Property
Public ReadOnly Property Items() As IQueryable(Of Item)
Get
Return _items.AsQueryable()
End Get
End Property
End Class
Public Class OrderItems
Inherits DataService(Of OrderItemData)
' This method is called only once to initialize
' service-wide policies.
Shared Sub InitializeService(ByVal config As DataServiceConfiguration)
config.SetEntitySetAccessRule("Orders", _
EntitySetRights.AllRead _
Or EntitySetRights.AllWrite)
config.SetEntitySetAccessRule("Items", _
EntitySetRights.AllRead _
Or EntitySetRights.AllWrite)
config.DataServiceBehavior.MaxProtocolVersion = DataServiceProtocolVersion.V3
End Sub
End Class
End Namespace
using System;
using System.Collections.Generic;
using System.Data.Services;
using System.Data.Services.Common;
using System.Linq;
namespace CustomDataService
{
[EntityPropertyMappingAttribute("Customer",
SyndicationItemProperty.AuthorName,
SyndicationTextContentKind.Plaintext, true)]
[EntityPropertyMapping("OrderId",
SyndicationItemProperty.Title,
SyndicationTextContentKind.Plaintext, false)]
[DataServiceKeyAttribute("OrderId")]
public class Order
{
public int OrderId { get; set; }
public string Customer { get; set; }
public IList<Item> Items { get; set; }
}
[EntityPropertyMappingAttribute("Product",
SyndicationItemProperty.CategoryTerm,
true, SyndicationCriteria.CategoryScheme,
"http://northwindtraders.com/Products")]
[EntityPropertyMappingAttribute("Url",
SyndicationItemProperty.LinkHref, false,
SyndicationCriteria.LinkRel,
"http://northwindtraders.com/ProductUrl")]
[DataServiceKeyAttribute("Product")]
public class Item
{
public string Product { get; set; }
public int Quantity { get; set; }
public string Url { get; set; }
}
public partial class OrderItemData
{
#region Populate Service Data
static IList<Order> _orders;
static IList<Item> _items;
static OrderItemData()
{
_orders = new Order[]{
new Order(){ OrderId=0, Customer = "Peter Franken", Items = new List<Item>()},
new Order(){ OrderId=1, Customer = "Ana Trujillo", Items = new List<Item>()}};
_items = new Item[]{
new Item(){ Product="Chai", Quantity=10,
Url="http://northwindtraders.com/Teas" },
new Item(){ Product="Chang", Quantity=25,
Url="http://northwindtraders.com/Specialty"},
new Item(){ Product="Aniseed Syrup", Quantity = 5,
Url="http://northwindtraders.com/Specialty"},
new Item(){ Product="Chef Anton's Cajun Seasoning",
Quantity=30, Url="http://northwindtraders.com/Spices"}};
_orders[0].Items.Add(_items[0]);
_orders[0].Items.Add(_items[1]);
_orders[1].Items.Add(_items[2]);
_orders[1].Items.Add(_items[3]);
}
#endregion
public IQueryable<Order> Orders
{
get { return _orders.AsQueryable(); }
}
public IQueryable<Item> Items
{
get { return _items.AsQueryable(); }
}
}
public class OrderItems : DataService<OrderItemData>
{
// This method is called only once to initialize
//service-wide policies.
public static void InitializeService(DataServiceConfiguration
config)
{
config.SetEntitySetAccessRule("Orders",
EntitySetRights.AllRead |
EntitySetRights.AllWrite);
config.SetEntitySetAccessRule("Items",
EntitySetRights.AllRead |
EntitySetRights.AllWrite);
config.DataServiceBehavior.MaxProtocolVersion =
DataServiceProtocolVersion.V3;
}
}
}
Das vorherige Beispiel gibt das folgende Ergebnis für den URI http://myservice/OrderItems.svc/Orders(0)?$expand=Items zurück.
<entry xml:base="https://localhost:12345/OrderItems.svc/"
xmlns:d="https://schemas.microsoft.com/ado/2007/08/dataservices"
xmlns:m="https://schemas.microsoft.com/ado/2007/08/dataservices/metadata"
xmlns="http://www.w3.org/2005/Atom">
<id>https://localhost:12345/OrderItems.svc/Orders(0)</id>
<title type="text">0</title>
<updated>2009-07-25T21:12:30Z</updated>
<author>
<name>Peter Franken</name>
</author>
<link rel="edit" title="Order" href="Orders(0)" />
<link rel="https://schemas.microsoft.com/ado/2007/08/dataservices/related/Items"
type="application/atom+xml;type=feed" title="Items" href="Orders(0)/Items">
<m:inline>
<feed>
<title type="text">Items</title>
<id>https://localhost:12345/OrderItems.svc/Orders(0)/Items</id>
<updated>2009-07-25T21:12:30Z</updated>
<link rel="self" title="Items" href="Orders(0)/Items" />
<entry>
<id>https://localhost:12345/OrderItems.svc/Items('Chai')</id>
<title type="text" />
<updated>2009-07-25T21:12:30Z</updated>
<author>
<name />
</author>
<link rel="edit" title="Item" href="Items('Chai')" />
<category term="CustomDataService.Item"
scheme="https://schemas.microsoft.com/ado/2007/08/dataservices/scheme" />
<content type="application/xml">
<m:properties>
<d:Product>Chai</d:Product>
<d:Quantity m:type="Edm.Int32">10</d:Quantity>
</m:properties>
</content>
<orders:productname
xmlns:orders="http://schema.examples.microsoft.com/dataservices">Chai</orders:productname>
</entry>
<entry>
<id>https://localhost:12345/OrderItems.svc/Items('Chang')</id>
<title type="text" />
<updated>2009-07-25T21:12:30Z</updated>
<author>
<name />
</author>
<link rel="edit" title="Item" href="Items('Chang')" />
<category term="CustomDataService.Item"
scheme="https://schemas.microsoft.com/ado/2007/08/dataservices/scheme" />
<content type="application/xml">
<m:properties>
<d:Product>Chang</d:Product>
<d:Quantity m:type="Edm.Int32">25</d:Quantity>
</m:properties>
</content>
<orders:productname
xmlns:orders="http://schema.examples.microsoft.com/dataservices">Chang</orders:productname>
</entry>
</feed>
</m:inline>
</link>
<category term="CustomDataService.Order"
scheme="https://schemas.microsoft.com/ado/2007/08/dataservices/scheme" />
<content type="application/xml">
<m:properties>
<d:Customer>Peter Franken</d:Customer>
</m:properties>
</content>
</entry>