查找父/子控件（元素节点）

Posted 2020-10-23 liu_xh

  1 /// <summary>
  2     /// 用于查找控件的工具类：找到父控件、子控件
  3     /// </summary>
  4     class ControlsSearchHelper
  5     {
  6         /// <summary>
  7         /// 查找父控件
  8         /// </summary>
  9         /// <typeparam name="T">父控件的类型</typeparam>
 10         /// <param name="obj">要找的是obj的父控件</param>
 11         /// <param name="name">想找的父控件的Name属性</param>
 12         /// <returns>目标父控件</returns>
 13         public static T GetParentObject<T>(DependencyObject obj, string name) where T : FrameworkElement
 14         {
 15             DependencyObject parent = VisualTreeHelper.GetParent(obj);
 16 
 17             while (parent != null)
 18             {
 19                 if (parent is T && (((T)parent).Name == name | string.IsNullOrEmpty(name)))
 20                 {
 21                     return (T)parent;
 22                 }
 23 
 24                 // 在上一级父控件中没有找到指定名字的控件，就再往上一级找
 25                 parent = VisualTreeHelper.GetParent(parent);
 26             }
 27 
 28             return null;
 29         }
 30 
 31 
 32         /// <summary>
 33         /// 查找子控件
 34         /// </summary>
 35         /// <typeparam name="T">子控件的类型</typeparam>
 36         /// <param name="obj">要找的是obj的子控件</param>
 37         /// <param name="name">想找的子控件的Name属性</param>
 38         /// <returns>目标子控件</returns>
 39         public static T GetChildObject<T>(DependencyObject obj, string name) where T : FrameworkElement
 40         {
 41             DependencyObject child = null;
 42             T grandChild = null;
 43 
 44             for (int i = 0; i <= VisualTreeHelper.GetChildrenCount(obj) - 1; i++)
 45             {
 46                 child = VisualTreeHelper.GetChild(obj, i);
 47 
 48                 if (child is T && (((T)child).Name == name | string.IsNullOrEmpty(name)))
 49                 {
 50                     return (T)child;
 51                 }
 52                 else
 53                 {
 54                     // 在下一级中没有找到指定名字的子控件，就再往下一级找
 55                     grandChild = GetChildObject<T>(child, name);
 56                     if (grandChild != null)
 57                         return grandChild;
 58                 }
 59             }
 60 
 61             return null;
 62 
 63         }
 64 
 65 
 66         /// <summary>
 67         /// 获取所有同一类型的子控件
 68         /// </summary>
 69         /// <typeparam name="T">子控件的类型</typeparam>
 70         /// <param name="obj">要找的是obj的子控件集合</param>
 71         /// <param name="name">想找的子控件的Name属性</param>
 72         /// <returns>子控件集合</returns>
 73         public static List<T> GetChildObjects<T>(DependencyObject obj, string name) where T : FrameworkElement
 74         {
 75             DependencyObject child = null;
 76             List<T> childList = new List<T>();
 77 
 78             for (int i = 0; i <= VisualTreeHelper.GetChildrenCount(obj) - 1; i++)
 79             {
 80                 child = VisualTreeHelper.GetChild(obj, i);
 81 
 82                 if (child is T && (((T)child).Name == name || string.IsNullOrEmpty(name)))
 83                 {
 84                     childList.Add((T)child);
 85                 }
 86 
 87                 childList.AddRange(GetChildObjects<T>(child, ""));
 88             }
 89 
 90             return childList;
 91 
 92         }
 93     }
 94 }
 95 
 96         public static IEnumerable<T> FindVisualChildren<T>(DependencyObject depObj) where T : DependencyObject
 97         {
 98             if (depObj != null)
 99             {
100                 for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
101                 {
102                     DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
103 
104                     if (child != null && child is T)
105                         yield return (T)child;
106 
107                     foreach (T childOfChild in FindVisualChildren<T>(child))
108                         yield return childOfChild;
109                 }
110             }
111         }