方法: Windows Presentation Foundation 要素にデータをバインドする (WCF Data Services)
WCF Data Services では、ListBox や ComboBox などの Windows Presentation Foundation (WPF) 要素を DataServiceCollection<T> のインスタンスにバインドできます。これにより、コントロールのデータへの変更と DataServiceContext との同期を維持するためにコントロールによって生成されるイベントを処理できます。 詳細については、「コントロールへのデータのバインド (WCF Data Services)」を参照してください。
このトピックの例では、Northwind サンプル データ サービスおよび自動生成されたクライアント データ サービス クラスを使用します。 このサービスおよびクライアント データ クラスは、WCF Data Services クイック スタートを完了したときに作成されます。
使用例
次の例は、WPF で SalesOrders ウィンドウを定義する Extensible Application Markup Language (XAML) の分離コード ページからの抜粋です。 ウィンドウが読み込まれると、国別にフィルターされた顧客を返すクエリの結果に基づいて DataServiceCollection<T> が作成されます。 このページングされた結果のすべてのページが関連する注文と一緒に読み込まれ、WPF ウィンドウのルート レイアウト コントロールである StackPanel の DataContext プロパティにバインドされます。 詳細については、「遅延コンテンツの読み込み (WCF Data Services)」を参照してください。
Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Data
Imports System.Windows.Documents
Imports System.Windows.Input
Imports System.Windows.Media
Imports System.Windows.Media.Imaging
Imports System.Windows.Navigation
Imports System.Windows.Shapes
Imports System.Data.Services.Client
Imports NorthwindClient.Northwind
Partial Public Class CustomerOrdersWpf3
Inherits Window
Private context As NorthwindEntities
Private trackedCustomers As DataServiceCollection(Of Customer)
Private Const customerCountry As String = "Germany"
Private Const svcUri As String = "https://localhost:12345/Northwind.svc/"
Private Sub Window_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
Try
' Initialize the context for the data service.
context = New NorthwindEntities(New Uri(svcUri))
' Create a LINQ query that returns customers with related orders.
Dim customerQuery = From cust In context.Customers _
Where cust.Country = customerCountry _
Select cust
' Create a new collection for binding based on the LINQ query.
trackedCustomers = New DataServiceCollection(Of Customer)(customerQuery)
' Load all pages of the response at once.
While trackedCustomers.Continuation IsNot Nothing
trackedCustomers.Load( _
context.Execute(Of Customer)(trackedCustomers.Continuation.NextLinkUri))
End While
' Bind the root StackPanel element to the collection
' related object binding paths are defined in the XAML.
Me.LayoutRoot.DataContext = trackedCustomers
Catch ex As DataServiceQueryException
MessageBox.Show("The query could not be completed:\n" + ex.ToString())
Catch ex As InvalidOperationException
MessageBox.Show("The following error occurred:\n" + ex.ToString())
End Try
End Sub
Private Sub customerIDComboBox_SelectionChanged(ByVal sender As Object, ByVal e As SelectionChangedEventArgs)
Dim selectedCustomer As Customer = _
CType(Me.customerIDComboBox.SelectedItem, Customer)
Try
If selectedCustomer.Orders.Count = 0 Then
' Load the first page of related orders for the selected customer.
context.LoadProperty(selectedCustomer, "Orders")
End If
' Load all remaining pages.
While selectedCustomer.Orders.Continuation IsNot Nothing
selectedCustomer.Orders.Load( _
context.Execute(Of Order)(selectedCustomer.Orders.Continuation.NextLinkUri))
End While
Catch ex As Exception
MessageBox.Show(ex.ToString())
End Try
End Sub
Private Sub saveChangesButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
Try
' Save changes to the data service.
context.SaveChanges()
Catch ex As Exception
MessageBox.Show(ex.ToString())
End Try
End Sub
End Class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Data.Services.Client;
using NorthwindClient.Northwind;
namespace NorthwindClient
{
public partial class CustomerOrdersWpf3 : Window
{
private NorthwindEntities context;
private DataServiceCollection<Customer> trackedCustomers;
private const string customerCountry = "Germany";
private const string svcUri = "https://localhost:12345/Northwind.svc/";
public CustomerOrdersWpf3()
{
InitializeComponent();
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
try
{
// Initialize the context for the data service.
context = new NorthwindEntities(new Uri(svcUri));
// Create a LINQ query that returns customers with related orders.
var customerQuery = from cust in context.Customers
where cust.Country == customerCountry
select cust;
// Create a new collection for binding based on the LINQ query.
trackedCustomers = new DataServiceCollection<Customer>(customerQuery);
// Load all pages of the response at once.
while (trackedCustomers.Continuation != null)
{
trackedCustomers.Load(
context.Execute<Customer>(trackedCustomers.Continuation.NextLinkUri));
}
// Bind the root StackPanel element to the collection;
// related object binding paths are defined in the XAML.
LayoutRoot.DataContext = trackedCustomers;
}
catch (DataServiceQueryException ex)
{
MessageBox.Show("The query could not be completed:\n" + ex.ToString());
}
catch (InvalidOperationException ex)
{
MessageBox.Show("The following error occurred:\n" + ex.ToString());
}
}
private void customerIDComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
Customer selectedCustomer =
this.customerIDComboBox.SelectedItem as Customer;
try
{
// Load the first page of related orders for the selected customer.
context.LoadProperty(selectedCustomer, "Orders");
// Load all remaining pages.
while (selectedCustomer.Orders.Continuation != null)
{
selectedCustomer.Orders.Load(
context.Execute<Order>(selectedCustomer.Orders.Continuation.NextLinkUri));
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
private void saveChangesButton_Click(object sender, RoutedEventArgs e)
{
try
{
// Save changes to the data service.
context.SaveChanges();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
}
}
次の XAML は、前の例の WPF の SalesOrders ウィンドウを定義します。
<Window x:Class="CustomerOrdersWpf3"
xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="https://schemas.openxmlformats.org/markup-compatibility/2006"
Height="423" Width="679" Loaded="Window_Loaded">
<StackPanel Orientation="Vertical" Height="Auto" Name="LayoutRoot" Width="Auto">
<Label Content="Customer ID" Margin="20,0,0,0" />
<ComboBox Name="customerIDComboBox" DisplayMemberPath="CustomerID" ItemsSource="{Binding}"
SelectionChanged="customerIDComboBox_SelectionChanged"
IsSynchronizedWithCurrentItem="True" SelectedIndex="0" Height="23" Width="120"
HorizontalAlignment="Left" Margin="20,0,0,0" VerticalAlignment="Center" />
<ListView ItemsSource="{Binding Path=Orders}" Name="ordersDataGrid" Margin="34,46,34,50">
<ListView.View>
<GridView AllowsColumnReorder="False" ColumnHeaderToolTip="Line Items">
<GridViewColumn DisplayMemberBinding="{Binding Path=OrderID, Mode=OneWay}"
Header="Order ID" Width="50"/>
<GridViewColumn DisplayMemberBinding="{Binding Path=OrderDate, Mode=TwoWay}"
Header="Order Date" Width="50"/>
<GridViewColumn DisplayMemberBinding="{Binding Path=Freight, Mode=TwoWay}"
Header="Freight Cost" Width="50"/>
</GridView>
</ListView.View>
</ListView>
<Button Name="saveChangesButton" Content="Save Changes" Click="saveChangesButton_Click"
Width="80" Height="30" Margin="450,0,0,0"/>
</StackPanel>
</Window>
次の例は、WPF で SalesOrders ウィンドウを定義する Extensible Application Markup Language (XAML) の分離コード ページからの抜粋です。 ウィンドウが読み込まれると、国別にフィルターされた顧客を関連するオブジェクトと一緒に返すクエリの結果に基づいて DataServiceCollection<T> が作成されます。 この結果は、WPF ウィンドウのルート レイアウト コントロールである StackPanel の DataContext プロパティにバインドされます。
Imports System
Imports System.Collections.Generic
Imports System.Linq
Imports System.Text
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Data
Imports System.Windows.Documents
Imports System.Windows.Input
Imports System.Windows.Media
Imports System.Windows.Media.Imaging
Imports System.Windows.Navigation
Imports System.Windows.Shapes
Imports System.Data.Services.Client
Imports NorthwindClient.Northwind
Partial Public Class CustomerOrdersWpf
Inherits Window
Private context As NorthwindEntities
Private trackedCustomers As DataServiceCollection(Of Customer)
Private Const customerCountry As String = "Germany"
Private Const svcUri As String = "https://localhost:12345/Northwind.svc/"
Private Sub Window_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
Try
' Initialize the context for the data service.
context = New NorthwindEntities(New Uri(svcUri))
' Create a LINQ query that returns customers with related orders.
Dim customerQuery = From cust In context.Customers.Expand("Orders") _
Where cust.Country = customerCountry _
Select cust
' Create a new collection for binding based on the LINQ query.
trackedCustomers = New DataServiceCollection(Of Customer)(customerQuery)
' Bind the root StackPanel element to the collection
' related object binding paths are defined in the XAML.
Me.LayoutRoot.DataContext = trackedCustomers
Catch ex As DataServiceQueryException
MessageBox.Show("The query could not be completed:\n" + ex.ToString())
Catch ex As InvalidOperationException
MessageBox.Show("The following error occurred:\n" + ex.ToString())
End Try
End Sub
Private Sub saveChangesButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
' Save changes to the data service.
context.SaveChanges()
End Sub
End Class
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Data.Services.Client;
using NorthwindClient.Northwind;
namespace NorthwindClient
{
public partial class CustomerOrdersWpf : Window
{
private NorthwindEntities context;
private DataServiceCollection<Customer> trackedCustomers;
private const string customerCountry = "Germany";
private const string svcUri = "https://localhost:12345/Northwind.svc/";
public CustomerOrdersWpf()
{
InitializeComponent();
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
try
{
// Initialize the context for the data service.
context = new NorthwindEntities(new Uri(svcUri));
// Create a LINQ query that returns customers with related orders.
var customerQuery = from cust in context.Customers.Expand("Orders")
where cust.Country == customerCountry
select cust;
// Create a new collection for binding based on the LINQ query.
trackedCustomers = new DataServiceCollection<Customer>(customerQuery);
// Bind the root StackPanel element to the collection;
// related object binding paths are defined in the XAML.
LayoutRoot.DataContext = trackedCustomers;
}
catch (DataServiceQueryException ex)
{
MessageBox.Show("The query could not be completed:\n" + ex.ToString());
}
catch (InvalidOperationException ex)
{
MessageBox.Show("The following error occurred:\n" + ex.ToString());
}
}
private void saveChangesButton_Click(object sender, RoutedEventArgs e)
{
// Save changes to the data service.
context.SaveChanges();
}
}
}
次の XAML は、前の例の WPF の SalesOrders ウィンドウを定義します。
<Window x:Class="CustomerOrdersWpf"
xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="https://schemas.openxmlformats.org/markup-compatibility/2006"
Height="423" Width="679" Loaded="Window_Loaded">
<StackPanel Orientation="Vertical" Height="Auto" Name="LayoutRoot" Width="Auto">
<Label Content="Customer ID" Margin="20,0,0,0" />
<ComboBox Name="customerIDComboBox" DisplayMemberPath="CustomerID" ItemsSource="{Binding}"
IsSynchronizedWithCurrentItem="True" SelectedIndex="0" Height="23" Width="120"
HorizontalAlignment="Left" Margin="20,0,0,0" VerticalAlignment="Center" />
<ListView ItemsSource="{Binding Path=Orders}" Name="ordersDataGrid" Margin="34,46,34,50">
<ListView.View>
<GridView AllowsColumnReorder="False" ColumnHeaderToolTip="Line Items">
<GridViewColumn DisplayMemberBinding="{Binding Path=OrderID, Mode=OneWay}"
Header="Order ID" Width="50"/>
<GridViewColumn DisplayMemberBinding="{Binding Path=OrderDate, Mode=TwoWay}"
Header="Order Date" Width="50"/>
<GridViewColumn DisplayMemberBinding="{Binding Path=Freight, Mode=TwoWay}"
Header="Freight Cost" Width="50"/>
</GridView>
</ListView.View>
</ListView>
<Button Name="saveChangesButton" Content="Save Changes" Click="saveChangesButton_Click"
Width="80" Height="30" Margin="450,0,0,0"/>
</StackPanel>
</Window>