我使用这种方法并通过密码框，虽然这确实违反了MVVM，这对我来说是必不可少的，因为我正在使用一个内容控件与数据模板为我的登录在我的shell，这是一个复杂的shell环境。因此，访问shell背后的代码将是垃圾。

据我所知，我认为传递密码框与从后面的代码访问控制权是一样的。在这个实现中，我没有视图模型中的密码属性。

按钮命令

Command="{Binding Path=DataContext.LoginCommand, ElementName=MyShell}" CommandParameter="{Binding ElementName=PasswordBox}"

ViewModel

private void Login(object parameter)
{
    System.Windows.Controls.PasswordBox p = (System.Windows.Controls.PasswordBox)parameter;
    MessageBox.Show(p.Password);
}

我使用了一个身份验证检查，然后是一个中介类向View调用的子(它也实现了身份验证检查)，将密码写入数据类。

这不是一个完美的解决方案;但是，它弥补了我无法移动密码的问题。

以下是我的看法:

Using an attached property to bind the password defeats the purpose of securing the password. The Password property of a password box is not bindable for a reason. Passing the password box as command parameter will make the ViewModel aware of the control. This will not work if you plan to make your ViewModel reusable cross platform. Don't make your VM aware of your View or any other controls. I don't think introducing a new property, an interface, subscribing to password changed events or any other complicated things is necessary for a simple task of providing the password.

XAML

<PasswordBox x:Name="pbPassword" />
<Button Content="Login" Command="{Binding LoginCommand}" x:Name="btnLogin"/>

代码背后——使用代码背后并不一定违反MVVM。只要你不把任何业务逻辑放在里面。

btnLogin.CommandParameter = new Func<string>(()=>pbPassword.Password); 

ViewModel

LoginCommand = new RelayCommand<Func<string>>(getpwd=> { service.Login(username, getpwd()); });

这很简单。为password创建另一个属性，并将其与TextBox绑定

但所有输入操作都使用实际的密码属性执行

private string _Password;

    public string PasswordChar
    {
        get
        {
            string szChar = "";

            foreach(char szCahr in _Password)
            {
                szChar = szChar + "*";
            }

            return szChar;
        }

        set
        {
            _PasswordChar = value; NotifyPropertyChanged();
        }
    }

public string密码 { 得到 { 返回_Password; ｝

        set
        {
            _Password = value; NotifyPropertyChanged();
            PasswordChar = _Password;
        }
    }

不幸的是，我没有足够的代表来评论另一个答案:( 只是想继续“史蒂夫在指挥官”的回答。 更新他的“PasswordChanged”事件如下，如果你在一个视图上有多个PasswordBox，通过使用sender的Name属性，可以为所有的PasswordBox使用相同的PasswordChanged事件。可能有更好的方法来做到这一点，如果有任何理由不这样做，请告诉我:)

private void PasswordBox_PasswordChanged(object sender, RoutedEventArgs e)
    {
        if (sender is PasswordBox) { 
        if (this.DataContext != null)

        { ((dynamic)this.DataContext).GetType().GetProperty(((PasswordBox)sender).Name).SetValue((dynamic)this.DataContext, ((PasswordBox)sender).Password, null); }
    }
    }

对我来说，这两件事都不对:

实现明文密码属性 将PasswordBox作为命令参数发送给ViewModel

像Steve在CO中描述的那样传输SecurePassword (SecureString实例)似乎是可以接受的。我更喜欢行为而不是背后的代码，而且我还需要能够从视图模型重置密码。

Xaml (Password是ViewModel属性):

<PasswordBox>
    <i:Interaction.Behaviors>
        <behaviors:PasswordBinding BoundPassword="{Binding Password, Mode=TwoWay}" />
    </i:Interaction.Behaviors>
</PasswordBox>

行为:

using System.Security;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Interactivity;

namespace Evidence.OutlookIntegration.AddinLogic.Behaviors
{
    /// <summary>
    /// Intermediate class that handles password box binding (which is not possible directly).
    /// </summary>
    public class PasswordBoxBindingBehavior : Behavior<PasswordBox>
    {
        // BoundPassword
        public SecureString BoundPassword { get { return (SecureString)GetValue(BoundPasswordProperty); } set { SetValue(BoundPasswordProperty, value); } }
        public static readonly DependencyProperty BoundPasswordProperty = DependencyProperty.Register("BoundPassword", typeof(SecureString), typeof(PasswordBoxBindingBehavior), new FrameworkPropertyMetadata(OnBoundPasswordChanged));

        protected override void OnAttached()
        {
            this.AssociatedObject.PasswordChanged += AssociatedObjectOnPasswordChanged;
            base.OnAttached();
        }

        /// <summary>
        /// Link up the intermediate SecureString (BoundPassword) to the UI instance
        /// </summary>
        private void AssociatedObjectOnPasswordChanged(object s, RoutedEventArgs e)
        {
            this.BoundPassword = this.AssociatedObject.SecurePassword;
        }

        /// <summary>
        /// Reacts to password reset on viewmodel (ViewModel.Password = new SecureString())
        /// </summary>
        private static void OnBoundPasswordChanged(object s, DependencyPropertyChangedEventArgs e)
        {
            var box = ((PasswordBoxBindingBehavior)s).AssociatedObject;
            if (box != null)
            {
                if (((SecureString)e.NewValue).Length == 0)
                    box.Password = string.Empty;
            }
        }

    }
}