I found that the line, VisualTreeHelper.GetChildrenCount(depObj);, used in several examples above does not return a non-zero count for GroupBoxes, in particular, where the GroupBox contains a Grid, and the Grid contains children elements. I believe this may be because the GroupBox is not allowed to contain more than one child, and this is stored in its Content property. There is no GroupBox.Children type of property. I am sure I did not do this very efficiently, but I modified the first "FindVisualChildren" example in this chain as follows:

public IEnumerable<T> FindVisualChildren<T>(DependencyObject depObj) where T : DependencyObject 
{ 
    if (depObj != null) 
    {
        int depObjCount = VisualTreeHelper.GetChildrenCount(depObj); 
        for (int i = 0; i <depObjCount; i++) 
        { 
            DependencyObject child = VisualTreeHelper.GetChild(depObj, i); 
            if (child != null && child is T) 
            { 
                yield return (T)child; 
            }

            if (child is GroupBox)
            {
                GroupBox gb = child as GroupBox;
                Object gpchild = gb.Content;
                if (gpchild is T)
                {
                    yield return (T)child; 
                    child = gpchild as T;
                }
            }

            foreach (T childOfChild in FindVisualChildren<T>(child)) 
            { 
                yield return childOfChild; 
            } 
        }
    }
} 

请注意，使用VisualTreeHelper仅适用于派生自Visual或Visual3D的控件。如果你还需要检查其他元素(例如TextBlock, FlowDocument等)，使用VisualTreeHelper将抛出一个异常。

如果有必要，这里有一个回到逻辑树的替代方案:

http://www.hardcodet.net/2009/06/finding-elements-in-wpf-tree-both-ways

下面是另一个紧凑的版本，使用泛型语法:

    public static IEnumerable<T> FindLogicalChildren<T>(DependencyObject obj) where T : DependencyObject
    {
        if (obj != null) {
            if (obj is T)
                yield return obj as T;

            foreach (DependencyObject child in LogicalTreeHelper.GetChildren(obj).OfType<DependencyObject>()) 
                foreach (T c in FindLogicalChildren<T>(child)) 
                    yield return c;
        }
    }

对递归做了一点小小的改变，例如，你可以找到一个标签控件的子标签控件。

    public static DependencyObject FindInVisualTreeDown(DependencyObject obj, Type type)
    {
        if (obj != null)
        {
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(obj); i++)
            {
                DependencyObject child = VisualTreeHelper.GetChild(obj, i);

                if (child.GetType() == type)
                {
                    return child;
                }

                DependencyObject childReturn = FindInVisualTreeDown(child, type);
                if (childReturn != null)
                {
                    return childReturn;
                }
            }
        }

        return null;
    }

这是最简单的方法:

IEnumerable<myType> collection = control.Children.OfType<myType>(); 

其中控件是窗口的根元素。

编辑-正如评论中指出的那样。这只是一个层次的深度。查看一个更深入的选项的公认答案。

要获得特定类型的所有子元素的列表，您可以使用:

private static IEnumerable<DependencyObject> FindInVisualTreeDown(DependencyObject obj, Type type)
{
    if (obj != null)
    {
        if (obj.GetType() == type)
        {
            yield return obj;
        }

        for (var i = 0; i < VisualTreeHelper.GetChildrenCount(obj); i++)
        {
            foreach (var child in FindInVisualTreeDown(VisualTreeHelper.GetChild(obj, i), type))
            {
                if (child != null)
                {
                    yield return child;
                }
            }
        }
    }

    yield break;
}