什么是WPF Data Binding的“RelativeSource FindAncestor”做？ [英] What exactly does WPF Data Binding's "RelativeSource FindAncestor" do?

问题描述

我目前正在一个WPF用户控件中工作（我的XAML文件的根元素是UserControl），我知道这是在窗口内托管的。如何使用数据绑定访问Window的属性？

有谁知道为什么简单地

 < Binding RelativeSource ={RelativeSource FindAncestor，AncestorType = {x：Type Window}}Path =.../> 
  

不工作？我得到的错误信息是：

System.Windows.Data警告：4：找不到与引用'RelativeSource FindAncestor，AncestorType ='System.Windows.Window绑定的源'，AncestorLevel ='1'。

编辑：我最终使用了ArsenMkrt方法的变体，所以接受了他的回答。然而，我仍然有兴趣了解为什么FindAncestor不会正常工作。

解决方案

最好的方法是给出名称到UserControl

在UserControl中创建依赖关系属性MyProperty，使用双向绑定并将其绑定到主窗口中，而不是像UserControl中的绑定一样这样

 < UserControl x：Name =myControl> 
< Label Content = {Binding ElementName = myControl，Path = MyProperty} /> 
< / UserControl> 
  

I am currently working within a WPF user control (the root element of my XAML file is "UserControl"), which I know is being hosted inside a Window. How can I access a property of the Window using data binding?

Does anyone know why simply

<Binding RelativeSource="{RelativeSource FindAncestor, AncestorType={x:Type Window}}" Path="..." />

does not work? The error message I get is:

System.Windows.Data Warning: 4 : Cannot find source for binding with reference 'RelativeSource FindAncestor, AncestorType='System.Windows.Window', AncestorLevel='1''.

Edit: I ended up using a variation on ArsenMkrt's approach, so have accepted his answer. However, I am still interested in finding out why FindAncestor does not "just work".

解决方案

The best way is to give a name to UserControl

Create dependency property MyProperty in UserControl with two way binding and bind it in main Window, than bind in UserControl like this

<UserControl x:Name = "myControl">
     <Label Content={Binding ElementName= myControl, Path=MyProperty}/>
</UserControl>

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