C# 如何初始化OneWayToSource依赖项属性?
我的控件中有一个dependency属性,它被绑定到视图模型的OneWayToSource。我不知道如何用非静态值初始化它。如果我尝试在控件的构造函数中初始化它,则属性值会更改为所需的值,但由于某些原因会立即更改回。考虑这个代码: ButterflyControl.xaml.csC# 如何初始化OneWayToSource依赖项属性?,c#,wpf,C#,Wpf,我的控件中有一个dependency属性,它被绑定到视图模型的OneWayToSource。我不知道如何用非静态值初始化它。如果我尝试在控件的构造函数中初始化它,则属性值会更改为所需的值,但由于某些原因会立即更改回。考虑这个代码: ButterflyControl.xaml.cs using System; using System.Diagnostics; using System.Windows; namespace OneWayToSourceTest { public part
using System;
using System.Diagnostics;
using System.Windows;
namespace OneWayToSourceTest
{
public partial class ButterflyControl
{
public ButterflyControl()
{
InitializeComponent();
RefreshAction = Refresh;
}
public static readonly DependencyProperty RefreshActionProperty = DependencyProperty.Register(
name: nameof(RefreshAction),
propertyType: typeof(Action),
ownerType: typeof(ButterflyControl),
typeMetadata: new PropertyMetadata(null, RefreshActionPropertyChanged));
public Action RefreshAction
{
get => (Action)GetValue(RefreshActionProperty);
set => SetValue(RefreshActionProperty, value);
}
private static void RefreshActionPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
{
// For debugging purposes, observe changed to the RefreshAction property.
Debug.WriteLine("RefreshAction changed from '{0}' to '{1}'", (e.OldValue as Action)?.Method.Name, (e.NewValue as Action)?.Method.Name);
}
private void Refresh()
{
// Refresh code goes here.
}
}
}
using System;
namespace OneWayToSourceTest
{
public static class Startup
{
[STAThread]
public static void Main()
{
MainWindow window = new MainWindow();
}
}
}
ButterflyControl.xaml
<UserControl x:Class="OneWayToSourceTest.ButterflyControl"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
mc:Ignorable="d"
d:DesignHeight="450" d:DesignWidth="800" >
<Grid />
</UserControl>
<Window x:Class="OneWayToSourceTest.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:oneWayToSourceTest="clr-namespace:OneWayToSourceTest"
mc:Ignorable="d"
Title="MainWindow" Height="450" Width="800">
<oneWayToSourceTest:ButterflyControl RefreshAction="{Binding RefreshAction, Mode=OneWayToSource}" />
</Window>
运行此程序时,输出窗口显示:
RefreshAction从“”更改为“刷新”RefreshAction从“刷新”更改为“”
我是否在某个地方犯了错误,或者我采取了错误的方法?如果我采取了错误的方法,那么用非静态值初始化OneWayToSource依赖项属性的合适方法是什么?将初始化移动到已加载的事件处理程序,该处理程序在绑定建立后调用
public ButterflyControl()
{
InitializeComponent();
Loaded += (s, e) => RefreshAction = Refresh;
}
有关更多信息,请参阅