如何按名称或类型查找WPF控件?
我需要在WPF控件层次结构中搜索与给定名称或类型匹配的控件。如何执行此操作?您可以使用查找控件。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如何按名称或类型查找WPF控件?,wpf,controls,find,Wpf,Controls,Find,我需要在WPF控件层次结构中搜索与给定名称或类型匹配的控件。如何执行此操作?您可以使用查找控件。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&g
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);
}
}
}
公共静态类UIHelper
{
///
///在可视树上查找给定项的父项。
///
///查询项的类型。
///查询项的直接或间接子项。
///与提交的类型参数匹配的第一个父项。
///如果找不到匹配项,则返回空引用。
公共静态T FindVisualParent(DependencyObject子级)
其中T:DependencyObject
{
//获取父项
DependencyObject parentObject=VisualTreeHelper.GetParent(子级);
//我们已经到了树的尽头
if(parentObject==null)返回null;
//检查父项是否与我们要查找的类型匹配
T parent=parentObject作为T;
如果(父项!=null)
{
返回父母;
}
其他的
{
//使用递归继续下一个级别
返回FindVisualParent(父对象);
}
}
}
可以这样称呼:
Window owner = UIHelper.FindVisualParent<Window>(myControl);
var child = FindChild(parent, child =>
{
var textBlock = child as TextBlock;
if (textBlock != null && textBlock.Name == "MyTextBlock")
return true;
else
return false;
}) as TextBlock;
windowowner=UIHelper.findvisualpart(myControl);
这将消除一些元素-您应该像这样扩展它,以支持更广泛的控件阵列。要进行简短的讨论,请看一看
//
///UI相关任务的帮助器方法。
///
公共静态类UIHelper
{
///
///在可视树上查找给定项的父项。
///
///查询项的类型。
///一个孩子的直接或间接的孩子
///查询的项目。
///与提交的项目匹配的第一个父项
///类型参数。如果找不到匹配项,则为空
///正在返回引用。
公共静态T TryFindParent(DependencyObject子对象)
其中T:DependencyObject
{
//获取父项
DependencyObject parentObject=GetParentObject(子对象);
//我们已经到了树的尽头
if(parentObject==null)返回null;
//检查父项是否与我们要查找的类型匹配
T parent=parentObject作为T;
如果(父项!=null)
{
返回父母;
}
其他的
{
//使用递归继续下一个级别
返回TryFindParent(parentObject);
}
}
///
///此方法是WPF的替代方法
///方法,其中
///支持内容元素。请注意,对于内容元素,
///此方法返回到元素的逻辑树!
///
///要处理的项目。
///已提交项目的父项(如果可用)。否则
///空。
公共静态DependencyObject GetParentObject(DependencyObject子对象)
{
if(child==null)返回null;
ContentElement=子元素作为ContentElement;
if(contentElement!=null)
{
DependencyObject parent=ContentOperations.GetParent(contentElement);
如果(parent!=null)返回parent;
FrameworkContentElement fce=作为FrameworkContentElement的contentElement;
返回fce!=null?fce.父项:null;
}
//如果它不是ContentElement,请依赖VisualTreeHelper
返回VisualTreeHelper.GetParent(子级);
}
}
您还可以使用按名称查找元素
鉴于:
<UserControl ...>
<TextBlock x:Name="myTextBlock" />
</UserControl>
当然,因为它是使用x:Name定义的,所以您可以只引用生成的字段,但是您可能希望动态地而不是静态地查找它
这种方法也适用于模板,其中命名项出现多次(每次使用模板一次)。我可能只是在重复其他人,但我确实有一段代码,它使用FindChild()方法扩展DependencyObject类,该方法将按类型和名称获取子对象。只是包括和使用
public static class UIChildFinder
{
public static DependencyObject FindChild(this DependencyObject reference, string childName, Type childType)
{
DependencyObject foundChild = null;
if (reference != null)
{
int childrenCount = VisualTreeHelper.GetChildrenCount(reference);
for (int i = 0; i < childrenCount; i++)
{
var child = VisualTreeHelper.GetChild(reference, i);
// If the child is not of the request child type child
if (child.GetType() != childType)
{
// recursively drill down the tree
foundChild = FindChild(child, childName, childType);
}
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 = child;
break;
}
}
else
{
// child element found.
foundChild = child;
break;
}
}
}
return foundChild;
}
}
公共静态类UIChildFinder
{
公共静态DependencyObject FindChild(此DependencyObject引用,字符串childName,类型childType)
{
DependencyObject foundChild=null;
如果(引用!=null)
{
int childrenCount=visualtreeheloper.GetChildrenCount(参考);
for(int i=0;i
希望您觉得它有用。我将John Myczek使用的模板格式与上面Tri Q的算法相结合,创建了一个可以在任何父级上使用的findChild算法。请记住,递归地向下搜索一棵树可能是一个漫长的过程。我只是在一个WPF应用程序上对此进行了抽查,请评论您可能发现的任何错误,我将更正我的代码 是查看可视化树的有用工具-我强烈建议使用它
public static class UIChildFinder
{
public static DependencyObject FindChild(this DependencyObject reference, string childName, Type childType)
{
DependencyObject foundChild = null;
if (reference != null)
{
int childrenCount = VisualTreeHelper.GetChildrenCount(reference);
for (int i = 0; i < childrenCount; i++)
{
var child = VisualTreeHelper.GetChild(reference, i);
// If the child is not of the request child type child
if (child.GetType() != childType)
{
// recursively drill down the tree
foundChild = FindChild(child, childName, childType);
}
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 = child;
break;
}
}
else
{
// child element found.
foundChild = child;
break;
}
}
}
return foundChild;
}
}
/// <summary>
/// Finds a Child of a given item in the visual tree.
/// </summary>
/// <param name="parent">A direct parent of the queried item.</param>
/// <typeparam name="T">The type of the queried item.</typeparam>
/// <param name="childName">x:Name or Name of child. </param>
/// <returns>The first parent item that matches the submitted type parameter.
/// If not matching item can be found,
/// a null parent is being returned.</returns>
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;
}
}
else
{
// child element found.
foundChild = (T)child;
break;
}
}
return foundChild;
}
TextBox foundTextBox =
UIHelper.FindChild<TextBox>(Application.Current.MainWindow, "myTextBoxName");
public static T FindChild<T>(DependencyObject depObj, string childName)
where T : DependencyObject
{
// Confirm obj is valid.
if (depObj == null) return null;
// success case
if (depObj is T && ((FrameworkElement)depObj).Name == childName)
return depObj as T;
for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
{
DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
//DFS
T obj = FindChild<T>(child, childName);
if (obj != null)
return obj;
}
return null;
}
public static class FrameworkElementExtension
{
public static object[] FindControls(
this FrameworkElement f, Type childType, int maxDepth)
{
return RecursiveFindControls(f, childType, 1, maxDepth);
}
private static object[] RecursiveFindControls(
object o, Type childType, int depth, int maxDepth = 0)
{
List<object> list = new List<object>();
var attrs = o.GetType()
.GetCustomAttributes(typeof(ContentPropertyAttribute), true);
if (attrs != null && attrs.Length > 0)
{
string childrenProperty = (attrs[0] as ContentPropertyAttribute).Name;
foreach (var c in (IEnumerable)o.GetType()
.GetProperty(childrenProperty).GetValue(o, null))
{
if (c.GetType().FullName == childType.FullName)
list.Add(c);
if (maxDepth == 0 || depth < maxDepth)
list.AddRange(RecursiveFindControls(
c, childType, depth + 1, maxDepth));
}
}
return list.ToArray();
}
}
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();
}
}
public static object[] FindControls(this FrameworkElement f, Type childType, int maxDepth)
{
return RecursiveFindControls(f, childType, 1, maxDepth);
}
private static object[] RecursiveFindControls(object o, Type childType, int depth, int maxDepth = 0)
{
List<object> list = new List<object>();
var attrs = o.GetType().GetCustomAttributes(typeof(ContentPropertyAttribute), true);
if (attrs != null && attrs.Length > 0)
{
string childrenProperty = (attrs[0] as ContentPropertyAttribute).Name;
if (String.Equals(childrenProperty, "Content") || String.Equals(childrenProperty, "Children"))
{
var collection = o.GetType().GetProperty(childrenProperty).GetValue(o, null);
if (collection is System.Windows.Controls.UIElementCollection) // snelson 6/6/11
{
foreach (var c in (IEnumerable)collection)
{
if (c.GetType().FullName == childType.FullName)
list.Add(c);
if (maxDepth == 0 || depth < maxDepth)
list.AddRange(RecursiveFindControls(
c, childType, depth + 1, maxDepth));
}
}
else if (collection != null && collection.GetType().BaseType.Name == "Panel") // snelson 6/6/11; added because was skipping control (e.g., System.Windows.Controls.Grid)
{
if (maxDepth == 0 || depth < maxDepth)
list.AddRange(RecursiveFindControls(
collection, childType, depth + 1, maxDepth));
}
}
}
return list.ToArray();
}
public static T FindVisualAncestorOfType<T>(this DependencyObject Elt)
where T : DependencyObject
{
for (DependencyObject parent = VisualTreeHelper.GetParent(Elt);
parent != null; parent = VisualTreeHelper.GetParent(parent))
{
T result = parent as T;
if (result != null)
return result;
}
return null;
}
Window window = ExampleTextBox.FindVisualAncestorOfType<Window>();
public static IEnumerable<T> FindVisualChildren<T>(DependencyObject parent)
where T : DependencyObject
{
int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < childrenCount; i++)
{
var child = VisualTreeHelper.GetChild(parent, i);
var childType = child as T;
if (childType != null)
{
yield return (T)child;
}
foreach (var other in FindVisualChildren<T>(child))
{
yield return other;
}
}
}
public static IEnumerable<T> SelectAllRecursively<T>(this IEnumerable<T> items, Func<T, IEnumerable<T>> func)
{
return (items ?? Enumerable.Empty<T>()).SelectMany(o => new[] { o }.Concat(SelectAllRecursively(func(o), func)));
}
public static IEnumerable<DependencyObject> FindChildren(this DependencyObject obj)
{
return Enumerable.Range(0, VisualTreeHelper.GetChildrenCount(obj))
.Select(i => VisualTreeHelper.GetChild(obj, i));
}
public static IEnumerable<DependencyObject> FindAllChildren(this DependencyObject obj)
{
return obj.FindChildren().SelectAllRecursively(o => o.FindChildren());
}
<TextBlock x:Name="txtblock" FontSize="24" >Hai Welcom to this page
</TextBlock>
var txtblock = sender as Textblock;
txtblock.Foreground = "Red"
Binding="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type <TypeToFind>}}}"
public static DependencyObject FindChild(DependencyObject parent, Func<DependencyObject, bool> predicate)
{
if (parent == null) return null;
int childrenCount = VisualTreeHelper.GetChildrenCount(parent);
for (int i = 0; i < childrenCount; i++)
{
var child = VisualTreeHelper.GetChild(parent, i);
if (predicate(child))
{
return child;
}
else
{
var foundChild = FindChild(child, predicate);
if (foundChild != null)
return foundChild;
}
}
return null;
}
var child = FindChild(parent, child =>
{
var textBlock = child as TextBlock;
if (textBlock != null && textBlock.Name == "MyTextBlock")
return true;
else
return false;
}) as TextBlock;
[CanBeNull]
public static T FindAncestor<T>(DependencyObject d) where T : DependencyObject
{
while (true)
{
d = VisualTreeHelper.GetParent(d);
if (d == null)
return null;
var t = d as T;
if (t != null)
return t;
}
}
[CanBeNull]
public static T FindAncestor<T>(DependencyObject d) where T : DependencyObject
{
while (true)
{
d = VisualTreeHelper.GetParent(d);
if (d == null)
return null;
if (d is T t)
return t;
}
}
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;
}
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;
}
}