BindingExpression.DataItem 属性

定义

获取此 BindingExpression 使用的绑定源对象。Gets the binding source object that this BindingExpression uses.

public:
 property System::Object ^ DataItem { System::Object ^ get(); };
public object DataItem { get; }
member this.DataItem : obj
Public ReadOnly Property DataItem As Object

属性值

Object

BindingExpression 使用的绑定源对象。The binding source object that this BindingExpression uses.

示例

下面的示例演示了一个 Click 事件处理程序的实现,该事件处理程序使用 GetBindingExpression 方法获取 BindingExpression ,然后调用 DataItem 属性来访问绑定源对象。The following example shows the implementation of a Click event handler that uses the GetBindingExpression method to obtain the BindingExpression and then calls the DataItem property to access the binding source object.

TextBlock SavingsText 是绑定目标对象,其 Text 属性是绑定目标属性。The TextBlock SavingsText is the binding target object, and its Text property is the binding target property.

private void OnRentRaise(Object sender, RoutedEventArgs args)
{
  // Update bills
  System.Random random = new System.Random();
  double i = random.Next(10);
  BindingExpression bindingExpression =
    BindingOperations.GetBindingExpression(SavingsText, TextBlock.TextProperty);
  SDKSample.NetIncome sourceData = (SDKSample.NetIncome) bindingExpression.DataItem;
  sourceData.Rent = (int)((1 + i / 100) * (double)sourceData.Rent);
}
Private Sub OnRentRaise(ByVal sender As Object, ByVal args As RoutedEventArgs)
    Dim _random As New System.Random()
    Dim num1 As Double = _random.Next(10)
    Dim expression1 As BindingExpression = BindingOperations.GetBindingExpression(Me.SavingsText, TextBlock.TextProperty)
    Dim income1 As NetIncome = DirectCast(expression1.DataItem, NetIncome)
    income1.Rent = CInt(((1 + (num1 / 100)) * income1.Rent))
End Sub

适用于