Out of the box you can't bind to the WPF PasswordBox's password property. This is done for security reason's. I think it's a bit overkill for most applications so I searched for a solution.
I found one here. The PasswordHelper is attached to the password box by calling the PasswordHelper.Attach property. The attached property PasswordHelper.Password provides a bindable copy of the original password property of the PasswordBox control.
The PasswordHelper class:
public static class PasswordHelper { public static readonly DependencyProperty PasswordProperty = DependencyProperty.RegisterAttached("Password", typeof(string), typeof(PasswordHelper), new FrameworkPropertyMetadata(string.Empty, OnPasswordPropertyChanged)); public static readonly DependencyProperty AttachProperty = DependencyProperty.RegisterAttached("Attach", typeof(bool), typeof(PasswordHelper), new PropertyMetadata(false, Attach)); private static readonly DependencyProperty IsUpdatingProperty = DependencyProperty.RegisterAttached("IsUpdating", typeof(bool), typeof(PasswordHelper)); public static void SetAttach(DependencyObject dp, bool value) { dp.SetValue(AttachProperty, value); } public static bool GetAttach(DependencyObject dp) { return (bool)dp.GetValue(AttachProperty); } public static string GetPassword(DependencyObject dp) { return (string)dp.GetValue(PasswordProperty); } public static void SetPassword(DependencyObject dp, string value) { dp.SetValue(PasswordProperty, value); } private static bool GetIsUpdating(DependencyObject dp) { return (bool)dp.GetValue(IsUpdatingProperty); } private static void SetIsUpdating(DependencyObject dp, bool value) { dp.SetValue(IsUpdatingProperty, value); } private static void OnPasswordPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e) { PasswordBox passwordBox = sender as PasswordBox; if (passwordBox == null) return; passwordBox.PasswordChanged -= PasswordChanged; if (!(bool)GetIsUpdating(passwordBox)) passwordBox.Password = (string)e.NewValue; passwordBox.PasswordChanged += PasswordChanged; } private static void Attach(DependencyObject sender, DependencyPropertyChangedEventArgs e) { PasswordBox passwordBox = sender as PasswordBox; if (passwordBox == null) return; if ((bool)e.OldValue) passwordBox.PasswordChanged -= PasswordChanged; if ((bool)e.NewValue) passwordBox.PasswordChanged += PasswordChanged; } private static void PasswordChanged(object sender, RoutedEventArgs e) { PasswordBox passwordBox = sender as PasswordBox; SetIsUpdating(passwordBox, true); SetPassword(passwordBox, passwordBox.Password); SetIsUpdating(passwordBox, false); } }
And in the XAML of your PasswordBox:
<PasswordBox x:Name="passwordBoxPwd" UserControls:PasswordHelper.Attach="True" UserControls:PasswordHelper.Password="{Binding MailPwd, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}" Margin="0 5 5 5"/>
I use it like this in my application and it works perfectly!