5、WPF_MVVM_绑定PasswordBox密码框

最新推荐文章于 2024-08-23 09:48:32 发布

weixin_44560027

最新推荐文章于 2024-08-23 09:48:32 发布

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本文链接：https://blog.youkuaiyun.com/weixin_44560027/article/details/119731270

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1、新建Common文件夹，文件夹新建“PasswordHelper.cs”类。
“PasswordHelper.cs”代码如下：

using System.Windows;
using System.Windows.Controls;
namespace CourseManagement.Common
{
    public class PasswordHelper
    {
        public static readonly DependencyProperty PasswordProperty = DependencyProperty.RegisterAttached("Password", typeof(string), typeof(PasswordHelper), new FrameworkPropertyMetadata("", new PropertyChangedCallback(OnPropertyChanged)));

        public static string GetPassword(DependencyObject d)
        {
            return d.GetValue(PasswordProperty).ToString();
        }
        public static void SetPassword(DependencyObject d, string value)
        {
            d.SetValue(PasswordProperty, value);
        }
        public static readonly DependencyProperty AttachProperty = DependencyProperty.RegisterAttached("Attach", typeof(bool), typeof(PasswordHelper), new FrameworkPropertyMetadata(default(bool), new PropertyChangedCallback(OnAttached)));

        public static bool GetAttach(DependencyObject d)
        {
            return (bool)d.GetValue(AttachProperty);
        }
        public static void SetAttach(DependencyObject d, bool value)
        {
            d.SetValue(AttachProperty, value);
        }
        static bool _isUpdating = false;
        private static void OnPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            PasswordBox password = d as PasswordBox;
            password.PasswordChanged -= Psssword_PasswordChanged;
            if(!_isUpdating)
                password.Password = e.NewValue?.ToString();
            password.PasswordChanged += Psssword_PasswordChanged;
        
        private static void OnAttached(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            PasswordBox password = d as PasswordBox;
            password.PasswordChanged += Psssword_PasswordChanged;
        }
        private static void Psssword_PasswordChanged(object sender, RoutedEventArgs e)
        {
            PasswordBox passwordBox = sender as PasswordBox;
            _isUpdating = true;
            SetPassword(passwordBox, passwordBox.Password);
            _isUpdating = false;
        
    }
}

2、LoginView.xaml代码如下：

xmlns:common="clr-namespace:CourseManagement.Common"

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                <PasswordBox Grid.Row="1" Height="42" Style="{DynamicResource PasswordBoxStyle}"
                             FontSize="16" Foreground="#DDD"
                             common:PasswordHelper.Attach="True"
                             common:PasswordHelper.Password="{Binding LoginModel.Password}">

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3、LoginViewModel.cs绑定密码

4、LoginModel.cs

5、发起通知，监听属性：

using System.ComponentModel;
using System.Runtime.CompilerServices;

namespace CourseManagement.Common
{
    public class NotifyBase : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged; 
        public void DoNotify([CallerMemberName] string propName="")
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propName));
        }
    }
}

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6、Common文件下的“CommandBase.cs”类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;
namespace CourseManagement.Common
{
    public class CommandBase : ICommand
    {
        public event EventHandler CanExecuteChanged;

        public bool CanExecute(object parameter)
        {
            return DoCanExecute?.Invoke(parameter) == true;
        }

        public void Execute(object parameter)
        {
            DoExecute?.Invoke(parameter);
        }
        public Action<object> DoExecute { get; set; }
        public Func<object, bool> DoCanExecute { get; set; }
    }
}

6、绑定成功：
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