您可以使用VisualTreeHelper来查找控件。下面是一个使用VisualTreeHelper查找指定类型的父控件的方法。您也可以使用VisualTreeHelper以其他方式查找控件。

public static class UIHelper
{
   /// <summary>
   /// Finds a parent of a given item on the visual tree.
   /// </summary>
   /// <typeparam name="T">The type of the queried item.</typeparam>
   /// <param name="child">A direct or indirect child of the queried item.</param>
   /// <returns>The first parent item that matches the submitted type parameter. 
   /// If not matching item can be found, a null reference is being returned.</returns>
   public static T FindVisualParent<T>(DependencyObject child)
     where T : DependencyObject
   {
      // get parent item
      DependencyObject parentObject = VisualTreeHelper.GetParent(child);

      // we’ve reached the end of the tree
      if (parentObject == null) return null;

      // check if the parent matches the type we’re looking for
      T parent = parentObject as T;
      if (parent != null)
      {
         return parent;
      }
      else
      {
         // use recursion to proceed with next level
         return FindVisualParent<T>(parentObject);
      }
   }
}

这样叫它:

Window owner = UIHelper.FindVisualParent<Window>(myControl);

这里有一些我经常使用的方法。

用法:

// Starts the search from thisUiElement (might be a UserContol, Window, etc..)
var combobox = thisUiElement.ChildOfType<ComboBox>();
var employeesListBox = thisUiElement.ChildOfName("EmployeesListBox");
// Starts the search from MainWindow to find the first DataGrid
var dataGrid = WpfUtils.ChildOfType<DataGrid>();
// Starts the search from MainWindow to find the all ListViews
List<ComboBox> allListViews = WpfUtils.ChildOfType<ListView>();
// Starts the search from MainWindow to find the element of name EmployeesComboBox
var combobox = WpfUtils.ChildOfName("EmployeesComboBox");

实现:

/*
using System.Collections.Generic;
using System.Windows;
using System.Windows.Media;

namespace WpfUtilities;
*/

public static class WpfUtils{

    public static Window AppMainWindow =>
        Application.Current?.MainWindow;

    #region Find By Type
    
    // Start the search from MainWindow, example usage: var combobox = WpfUtils.ChildOfType<ComboBox>();
    public static T ChildOfType<T>() where T : DependencyObject =>
        ChildOfType<T>(AppMainWindow);
        
    /// This will return the first child of type T
    public static T ChildOfType<T>(this DependencyObject parent)
        where T : DependencyObject
    {
        if (parent == null) return null;
        T child = default;
        var numVisuals = VisualTreeHelper.GetChildrenCount(parent);
        for (var i = 0; i < numVisuals; i++)
        {
            var v = VisualTreeHelper.GetChild(parent, i);
            child = v as T ?? v.ChildOfType<T>();
            if (child != null)
                break;
        }

        return child;
    }
    
    // Start the search from MainWindow, example usage: List<ComboBox> comboboxes = WpfUtils.ChildOfType<ComboBox>();
    public static IEnumerable<T> ChildrenOfType<T>() where T : DependencyObject =>
        ChildrenOfType<T>(AppMainWindow);
    
    /// This will not break the search when finding the first kid of type T, but it will keep searching to return all kids of type T
    public static IEnumerable<T> ChildrenOfType<T>(
        this DependencyObject parent) where T : DependencyObject
    {
        if (parent == null) yield break;
        var numVisuals = VisualTreeHelper.GetChildrenCount(parent);
        for (var i = 0; i < numVisuals; i++)
        {
            var child = VisualTreeHelper.GetChild(parent, i);
            if (child is T dependencyObject)
                yield return dependencyObject;

            foreach (var childOfChild in child.ChildrenOfType<T>())
                yield return childOfChild;
        }
    }
    
    #endregion  

    #region Find By Name
    
    /// If parent is null, the search will start from MainWindow, example usage: var combobox = WpfUtils.ChildOfName("EmployeesCombobox");
    public static FrameworkElement ChildOfName(string childName,
        DependencyObject parent = null)
    {
        parent ??= AppMainWindow;
        object child = null;
        var numVisuals = VisualTreeHelper.GetChildrenCount(parent);
        for (var i = 0; i < numVisuals; i++)
        {
            var v = VisualTreeHelper.GetChild(parent, i);
            child = v is FrameworkElement f && f.Name == childName
                ? f
                : ChildOfName(childName, v);

            if (child != null)
                break;
        }

        return child as FrameworkElement;
    }
    
    #endregion
    
    #region
    
    // Yet another useful method, if you are writing code in a .xaml.cs file and you want to get the parent of a type.. example usage: this.ParentOfType<Grid>(); this.ParentOfType<UserControl>(); this.ParentOfType<Window>(); 
    public static T ParentOfType<T>(this DependencyObject child) where T : DependencyObject
    {
        var parentDepObj = child;
        do
        {
            parentDepObj = VisualTreeHelper.GetParent(parentDepObj);
            if (parentDepObj is T parent) return parent;
        } while (parentDepObj != null);

        return null;
    }
    
    #endregion
}

因为这个问题很普遍，它可能会吸引人们去寻找非常琐碎的情况的答案:如果你只想要一个孩子而不是后代，你可以使用Linq:

private void ItemsControlItem_Loaded(object sender, RoutedEventArgs e)
{
    if (SomeCondition())
    {
        var children = (sender as Panel).Children;
        var child = (from Control child in children
                 where child.Name == "NameTextBox"
                 select child).First();
        child.Focus();
    }
}

或者显然的for循环遍历Children。

我找不到@CrimsonX或@Drew Noakes方法的控件，因为我的ControlTemplate位于一个单独的XAML文件中。 我用下面的方法找到了控件:

private Image backImage;
private void Diagram_Loaded(object sender, System.Windows.RoutedEventArgs e)
{
    // here is the example of the ControlTemplate declaration
    //<ControlTemplate x:Key="DiagramControlTemplate1" TargetType="{x:Type Diagram}">
    var ctrlTemplate = (ControlTemplate)FindResource("DiagramControlTemplate1");
    // diagram is the x:Name of TemplatedControl and, "backImage" is the name of control that I want to find.
    var imageControl = ctrlTemplate.FindName("backImage", diagram);
    if (imageControl != null)
    {
        this.backImage = (Image)imageControl;
    }
}

这对我很有用。

这些选项已经讨论了如何在c#中遍历可视化树。 使用RelativeSource标记扩展也可以遍历xaml中的可视树。msdn

按类型查找

Binding="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type <TypeToFind>}}}" 

这段代码只是修复了@CrimsonX回答的错误:

 public static T FindChild<T>(DependencyObject parent, string childName)
       where T : DependencyObject
    {    
      // Confirm parent and childName are valid. 
      if (parent == null) return null;

      T foundChild = null;

      int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
      for (int i = 0; i < childrenCount; i++)
      {
        var child = VisualTreeHelper.GetChild(parent, i);
        // If the child is not of the request child type child
        T childType = child as T;
        if (childType == null)
        {
          // recursively drill down the tree
          foundChild = FindChild<T>(child, childName);

          // If the child is found, break so we do not overwrite the found child. 
          if (foundChild != null) break;
        }
        else if (!string.IsNullOrEmpty(childName))
        {
          var frameworkElement = child as FrameworkElement;
          // If the child's name is set for search
          if (frameworkElement != null && frameworkElement.Name == childName)
          {
            // if the child's name is of the request name
            foundChild = (T)child;
            break;
          }

 // recursively drill down the tree
          foundChild = FindChild<T>(child, childName);

          // If the child is found, break so we do not overwrite the found child. 
          if (foundChild != null) break;


        else
        {
          // child element found.
          foundChild = (T)child;
          break;
        }
      }

      return foundChild;
    }  

你只需要继续递归调用方法，如果类型匹配，但名称不匹配(这发生在你传递FrameworkElement作为T时)，否则它将返回null，这是错误的。