【WPF】自定义PassWordBox (可以绑定的) 、SecureString类型

目的

自定义一个可以绑定的密码输入框

知识点：自定义控件、     SecureString类型

System.Security.SecureString(表示应保密的文本) 保存非托管内存中，需要用指针逐个字符的读取。

正常的String类型值,在脱离开作用域之后,其值在内存中并不会被立即销毁,这时如果有人恶意扫描你的内存,程序中所保存的机密信息就会暴露;于是就有了System.Security.SecureString,SecureString表示一个应保密的文本,它在初始化时就已被加密，并且脱离作用域后会被立即销毁;

 自定义用户控件

1、添加自定义用户控件类

 

 

 2、xaml代码

<UserControl x:Class="Login.Theme.CustomeControls.PasswordBoxBingable"
             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" 
             xmlns:local="clr-namespace:Login.Theme.CustomeControls"
             mc:Ignorable="d" 
             d:DesignHeight="40" d:DesignWidth="300">
    <!--DesignHeight和DesignWidth属性，它们在设计时控制用户控件的大小（在运行时，用户控件的大小将由容纳它的容器决定）-->
    <!--自定义控件中不支持 子定控件的style设置，要定义自定义控件样式只能在 使用控件的地方定义-->
    <Grid>
        <PasswordBox x:Name="Psb"
                 BorderBrush="White"
                 VerticalAlignment="Stretch"
                 VerticalContentAlignment="Center"
                 HorizontalAlignment="Stretch"
                 HorizontalContentAlignment="Left"
                 Padding="10,0,0,0"
                 BorderThickness="0"
                 Background="Transparent"
                >
            
        </PasswordBox>
    </Grid>
   
</UserControl>

 

 

注意：  d:DesignHeight="40" d:DesignWidth="300"，  DesignHeight和DesignWidth属性，它们在设计时控制用户控件的大小（在运行时，用户控件的大小将由容纳它的容器决定）

C#代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Security;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace Login.Resources.CustomeControls
{
    /// <summary>
    /// BingablePassword.xaml 的交互逻辑
    /// </summary>
    /// 
    public partial class PasswordBoxBingable : UserControl
    {
        public static readonly DependencyProperty PasswordProperty =
            DependencyProperty.Register("Password", typeof(SecureString), typeof(PasswordBoxBingable));
        public SecureString Password
        {
            get { return (SecureString)GetValue(PasswordProperty); }
            set { SetValue(PasswordProperty, value); }
        }
        public PasswordBoxBingable()
        {
            InitializeComponent();
            Psb.PasswordChanged += OnPasswordChanged;
        }

        private void OnPasswordChanged(object sender, RoutedEventArgs e)
        {
            Password = Psb.SecurePassword;
        }
    }
}

 

显示

 

 

 

 

 

 

 

 应用自定义控件

登入窗体 LoginView.xaml

1）在主窗体中 引入自定义控件PasswordBoxBingable所在的命名空间

<Window x:Class="Login.Views.LoginView"
        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:CustomControl="clr-namespace:Login.Resources.CustomeControls"

2）应用自定义控件PasswordBoxBingable，并且绑定 LoginViewModel.cs的password。

        <CustomControl:PasswordBoxBingable Style="{DynamicResource PasswordBoxBingableStyle2}"  x:Name="psp2"    
                                                       Password="{Binding Password,Mode=OneWayToSource,UpdateSourceTrigger=PropertyChanged}"
                                                        Height="40" 
                                                        Margin="20,20,20,0"/>

3）给自定义控件设置样式 PasswordBoxBingable，样式单独写入到PasswordBingableStyle.xaml 文件中。

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:CustomeControls="clr-namespace:Login.Resources.CustomeControls">
  

    <Style x:Key="PasswordBoxBingableStyle2" TargetType="{x:Type CustomeControls:PasswordBoxBingable}">
        <Setter Property="BorderThickness" Value="1"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type CustomeControls:PasswordBoxBingable}">
                    <Border x:Name="boder" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Padding="{TemplateBinding Padding}" SnapsToDevicePixels="true">
                        <ContentPresenter HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
                    </Border>
                    <ControlTemplate.Triggers>
                        <Trigger Property="IsEnabled" Value="False">
                            <Setter Property="Opacity" Value="0.56"/>
                        </Trigger>
                        <Trigger Property="IsMouseOver" Value="True">
                            <Setter Property="BorderBrush" Value="#7AAEE3"/>
                           
                        </Trigger>
                        <Trigger Property="IsMouseOver" Value="False">
                            <Setter Property="BorderBrush" Value="#A4A7AD"/>
                            
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>

    </Style>
</ResourceDictionary>

 

 4）登入窗体 LoginView.xaml.cs 

public partial class LoginView: Window
    {
        public LoginView()
        {
            InitializeComponent();
            this.DataContext = new LoginViewModel();
        }
}

5）部分LoginViewModel.cs 代码如下

public class LoginViewModel : BaseViewModel
    {

  public SecureString Password { get; set; }
        public string UserName{ get; set; }

}

 

最终效果如下：

 

 本文只为了介绍自定用户控件和SecureString类型的应用。