WPF 使用附加属性实现 PasswordBox 控件 Password 同步到 ViewModel

参考

• deepseek
• 豆包
• copilot
• https://www.wpfsoft.com/2023/10/26/2645.html
• https://www.cnblogs.com/sqwh-ww/p/14386439.html
• https://github.com/streesobrs/WPF.Streesobrs/blob/master/PersonalNotepad/Common/PasswordHelper.cs

环境

软件/系统	版本	说明
Windows	windows 10 专业版 22H2 64 位操作系统, 基于 x64 的处理器
Microsoft Visual Studio	Community 2022 (64 位) - Current 版本 17.14.9
Prism Template Pack	2.4.1	Microsoft Visual Studio 扩展
.NET	6
Prism.Unity	8.1.97	nuget依赖库（使用 Prism Template Pack 创建项目时选择的容器，使用模板创建的项目自动安装）
MaterialDesignThemes	5.2.1	nuget依赖库

正文

步骤

1. 实现 PasswordBoxHelper.cs
2. Login.xaml 页面附加属性类的命名空间 xmlns:helper="clr-namespace:WPFNetConnect.Helper"
3. 在控件中使用

   <PasswordBox
   	x:Name="LoginPasswordBox"
   	helper:PasswordBoxHelper.Password="{Binding Password, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
   	Style="{StaticResource LoginPasswordBox}" />
   

主要代码

1. PasswordBoxHelper.cs

   using System.Windows;
   using System.Windows.Controls;
   
   namespace WPFNetConnect.Helper
   {
   	public static class PasswordBoxHelper
   	{
   		public static string GetPassword(DependencyObject obj) => (string)obj.GetValue(PasswordProperty);
   
   		public static void SetPassword(DependencyObject obj, string value) => obj.SetValue(PasswordProperty, value);
   
   		public static readonly DependencyProperty PasswordProperty =
   			DependencyProperty.RegisterAttached("Password", typeof(string), typeof(PasswordBoxHelper),
   				new FrameworkPropertyMetadata(OnPasswordPropertyChangedCallback));
   
   		private static void OnPasswordPropertyChangedCallback(
   			DependencyObject d, DependencyPropertyChangedEventArgs e)
   		{
   			if (d is PasswordBox passwordBox)
   			{
   				passwordBox.PasswordChanged -= PasswordBox_PasswordChanged;
   				passwordBox.PasswordChanged += PasswordBox_PasswordChanged;
   			}
   		}
   
   		private static void PasswordBox_PasswordChanged(object sender, RoutedEventArgs e)
   		{
   			if (sender is PasswordBox passwordBox)
   			{
   				SetPassword(passwordBox, passwordBox.Password);
   			}
   		}
   	}
   }
   

2. Login.xaml

   <Window
   	x:Class="WPFNetConnect.Views.Login"
   	xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
   	xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
   	xmlns:helper="clr-namespace:WPFNetConnect.Helper"
   	xmlns:prism="http://prismlibrary.com/"
   	Title="{Binding Title}"
   	Width="1280"
   	Height="800"
   	prism:ViewModelLocator.AutoWireViewModel="True"
   	WindowStartupLocation="CenterScreen">
   	<Window.Resources>
   		<ResourceDictionary>
   			<!--  单独引入外部样式  -->
   			<ResourceDictionary.MergedDictionaries>
   				<ResourceDictionary Source="/Styles/LoginStyle.xaml" />
   			</ResourceDictionary.MergedDictionaries>
   		</ResourceDictionary>
   	</Window.Resources>
   	<Grid>
   		<Grid.ColumnDefinitions>
   			<ColumnDefinition Width="512" />
   			<ColumnDefinition />
   		</Grid.ColumnDefinitions>
   		<Image Grid.Column="0" Style="{StaticResource LoginLeft}" />
   		<StackPanel Grid.Column="1" Style="{StaticResource LoginRight}">
   			<Label Style="{StaticResource LoginTitle}">欢迎回来</Label>
   			<Label Style="{StaticResource LoginDesc}">登陆到您的账户</Label>
   			<Label Style="{StaticResource LoginAccountTitle}">用户名</Label>
   			<TextBox
   				x:Name="LoginAccountTextBox"
   				Style="{StaticResource LoginAccountTextBox}"
   				Text="{Binding Path=Account}" />
   			<Label Style="{StaticResource LoginPasswordTitle}">密码</Label>
   			<PasswordBox
   				x:Name="LoginPasswordBox"
   				helper:PasswordBoxHelper.Password="{Binding Password, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
   				Style="{StaticResource LoginPasswordBox}" />
   			<Button Command="{Binding SubmitBtnCommand}" Style="{StaticResource LoginSubmitButton}">
   				登录
   			</Button>
   			<Label Style="{StaticResource LoginErrorTip}">无法登录？联系管理员</Label>
   		</StackPanel>
   		<Label
   			Grid.Column="1"
   			Content="NetConnect v1.0.5"
   			Style="{StaticResource LoginVersion}" />
   	</Grid>
   </Window>