在代码隐藏中的DataTemplate中找到一个WPF元素

public static T FindVisualChild<T>(DependencyObject obj) where T : DependencyObject
{
    for (int i = 0; i< VisualTreeHelper.GetChildrenCount(obj); i++)
    {
        DependencyObject child = VisualTreeHelper.GetChild(obj, i);
        if (child is T)
        {
            return (T)child;
        }
        else
        {
            T childOfChild = FindVisualChild<T>(child);
            if (childOfChild != null)
            {
                return childOfChild;
            }
        }
    }
    return null;
}

var dataTemplate = new DataTemplate();
var element = FindVisualChild<WPF元素类型>(dataTemplate);

public static T FindLogicalChild<T>(DependencyObject obj) where T : DependencyObject
{
    foreach (object child in LogicalTreeHelper.GetChildren(obj))
    {
        if (child is T)
        {
            return (T)child;
        }
        else if (child is DependencyObject)
        {
            T childOfChild = FindLogicalChild<T>((DependencyObject)child);
            if (childOfChild != null)
            {
                return childOfChild;
            }
        }
    }
    return null;
}

var dataTemplate = new DataTemplate();
var element = FindLogicalChild<WPF元素类型>(dataTemplate);