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如何：使用程式碼建立繫結

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此範例示範如何在程式碼中建立及設定 Binding。

範例

FrameworkElement 類別和 FrameworkContentElement 類別都會公開 SetBinding 方法。 如果您要繫結繼承這些類別其中之一的元素，您可以直接呼叫 SetBinding 方法。

下列範例會建立名為 MyData 的類別，其中包含名為 MyDataProperty 的屬性。

public class MyData : INotifyPropertyChanged
{
    private string myDataProperty;

    public MyData() { }

    public MyData(DateTime dateTime)
    {
        myDataProperty = "Last bound time was " + dateTime.ToLongTimeString();
    }

    public String MyDataProperty
    {
        get { return myDataProperty; }
        set
        {
            myDataProperty = value;
            OnPropertyChanged("MyDataProperty");
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;

    private void OnPropertyChanged(string info)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null)
        {
            handler(this, new PropertyChangedEventArgs(info));
        }
    }
}

Public Class MyData
    Implements INotifyPropertyChanged

    ' Events
    Public Event PropertyChanged As PropertyChangedEventHandler _
        Implements INotifyPropertyChanged.PropertyChanged

    ' Methods
    Public Sub New()
    End Sub

    Public Sub New(ByVal dateTime As DateTime)
        Me.MyDataProperty = ("Last bound time was " & dateTime.ToLongTimeString)
    End Sub

    Private Sub OnPropertyChanged(ByVal info As String)
        RaiseEvent PropertyChanged(Me, New PropertyChangedEventArgs(info))
    End Sub


    ' Properties
    Public Property MyDataProperty As String
        Get
            Return Me._myDataProperty
        End Get
        Set(ByVal value As String)
            Me._myDataProperty = value
            Me.OnPropertyChanged("MyDataProperty")
        End Set
    End Property


    ' Fields
    Private _myDataProperty As String
End Class

下列範例示範如何建立繫結物件來設定繫結的來源。 此範例會使用 SetBinding，將 Text 的 myText 屬性 (即 TextBlock 控制項) 繫結至 MyDataProperty。

// Make a new source.
MyData myDataObject = new MyData(DateTime.Now);
Binding myBinding = new Binding("MyDataProperty");
myBinding.Source = myDataObject;
// Bind the new data source to the myText TextBlock control's Text dependency property.
myText.SetBinding(TextBlock.TextProperty, myBinding);

' Make a new source.
Dim data1 As New MyData(DateTime.Now)
Dim binding1 As New Binding("MyDataProperty")
binding1.Source = data1
' Bind the new data source to the myText TextBlock control's Text dependency property.
Me.myText.SetBinding(TextBlock.TextProperty, binding1)

如需完整的程式碼範例，請參閱僅限程式碼繫結範例。

您可以使用 SetBinding 類別的 SetBinding 靜態方法，而不是呼叫 BindingOperations。 下列範例會呼叫 BindingOperations.SetBinding，而不是 FrameworkElement.SetBinding，來將 myText 繫結至 myDataProperty。

//make a new source
MyData myDataObject = new MyData(DateTime.Now);
Binding myBinding = new Binding("MyDataProperty");
myBinding.Source = myDataObject;
BindingOperations.SetBinding(myText, TextBlock.TextProperty, myBinding);

Dim myDataObject As New MyData(DateTime.Now)
Dim myBinding As New Binding("MyDataProperty")
myBinding.Source = myDataObject
BindingOperations.SetBinding(myText, TextBlock.TextProperty, myBinding)

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