如何:使用程式碼建立繫結
此範例示範如何在程式碼中建立和設定 Binding 。
範例
類別 FrameworkElement 和 FrameworkContentElement 類別都會公開 SetBinding
方法。 如果您要系結繼承其中一個類別的專案,您可以直接呼叫 SetBinding 方法。
下列範例會建立名為 的類別, MyData
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系結物件來設定系結的來源。 此範例會使用 SetBinding 將 的 屬性 myText
系結 Text 至 MyDataProperty
,也就是 TextBlock 控制項。
// 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 僅限程式碼系結範例 。
您可以使用 類別的 BindingOperations 靜態方法, SetBinding 而不是呼叫 SetBinding 。 下列範例會呼叫 BindingOperations.SetBinding , FrameworkElement.SetBinding 而不是系結 myText
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)