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C# WPF 表单更改提示

内容目录

实现效果
业务场景
编码实现
本文参考
源码下载

1.实现效果

未做修改的表单展示

表单变化，关闭窗体提示

来个Gif动态操作看看

2.业务场景

表单修改后，关闭窗体前检查提示

3.编码实现

3.1 添加Nuget库

使用 .Net Core 3.1 创建名为“ValidateDataChange”的WPF解决方案，添加两个Nuget库：MaterialDesignThemes和MaterialDesignColors。

MaterialDesign控件库

3.2 工程结构

4个文件变动：

App.xaml：添加MD控件样式
MainWindow.xaml：主窗口实现效果
MainWindow.xaml.cs：主窗口后台绑定及关闭验证
Contact.cs：绑定的实体

3.3 App.xaml引入MD控件样式

<Application x:Class="ValidateDataChange.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:ValidateDataChange"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Light.xaml"/>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Defaults.xaml"/>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignColors;component/Themes/Recommended/Primary/MaterialDesignColor.DeepPurple.xaml"/>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignColors;component/Themes/Recommended/Accent/MaterialDesignColor.Blue.xaml"/>
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>

3.4 主窗体 MainWindow.xaml

表单展示，使用MD控件的Snackbar作为消息提示

<Window x:Class="ValidateDataChange.MainWindow"
        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:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:ValidateDataChange"
        mc:Ignorable="d"
        xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
        Title="编辑联系人" Height="500" Width="400" ResizeMode="NoResize" FontFamily="Roboto" 
        FontSize="14" WindowStartupLocation="CenterScreen" Closing="Window_Closing">
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="100"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>
        <materialDesign:ColorZone Mode="PrimaryMid" Grid.Row="0" VerticalAlignment="Stretch">
            <TextBlock Text="联系人" VerticalAlignment="Center" Margin="20" FontSize="30"/>
        </materialDesign:ColorZone>

        <StackPanel Margin="10 30" Grid.Row="1">
            <Grid>
                <materialDesign:PackIcon Kind="Face" VerticalAlignment="Bottom" Margin="2 12" Foreground="{Binding BorderBrush, ElementName=TextBoxName}"/>
                <TextBox x:Name="TextBoxName" Margin="5" materialDesign:HintAssist.Hint="名字" Padding="8 0 0 0" Text="{Binding Name}"
                         Style="{StaticResource MaterialDesignFloatingHintTextBox}"/>
            </Grid>
            <Grid>
                <materialDesign:PackIcon Kind="At" VerticalAlignment="Bottom" Margin="2 12" Foreground="{Binding BorderBrush, ElementName=TextBoxEmail}"/>
                <TextBox x:Name="TextBoxEmail" Margin="5" materialDesign:HintAssist.Hint="邮件" Padding="8 0 0 0" Text="{Binding Email}"
                         Style="{StaticResource MaterialDesignFloatingHintTextBox}"/>
            </Grid>
            <Grid>
                <StackPanel Orientation="Horizontal" VerticalAlignment="Bottom" Margin="2 10">
                    <materialDesign:PackIcon Kind="Facebook" Foreground="{Binding BorderBrush, ElementName=TextBoxFacebook}"/>
                    <TextBlock Text="facebook.com/" Foreground="{Binding BorderBrush, ElementName=TextBoxFacebook}"/>
                </StackPanel>
                <TextBox x:Name="TextBoxFacebook" Margin="5" materialDesign:HintAssist.Hint="Facebook" Padding="54 0 0 0" Text="{Binding Facebook}"
                         Style="{StaticResource MaterialDesignFloatingHintTextBox}"/>
            </Grid>
        </StackPanel>
        <Button Grid.RowSpan="2" Margin="50 72" HorizontalAlignment="Right" VerticalAlignment="Top" Style="{StaticResource MaterialDesignFloatingActionAccentButton}"
                Click="Button_Click">
            <materialDesign:PackIcon Kind="ContentSave"/>
        </Button>

        <materialDesign:Snackbar Grid.Row="1" HorizontalAlignment="Stretch" x:Name="SnackbarUnsavedChanges" VerticalAlignment="Bottom">
            <materialDesign:SnackbarMessage
                Content="有未保存的更改，是否放弃修改？"
                ActionContent="放弃" ActionClick="SnackbarMessage_ActionClick"/>
        </materialDesign:Snackbar>
    </Grid>
</Window>

3.5 MainWindow.xaml.cs

数据绑定，窗体关闭前表单验证：简单使用hashcode判断绑定实体是否有变化。

using System;
using System.Collections.Generic;
using System.Linq;
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 ValidateDataChange
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        int hash;
        bool discardChanges;

        public MainWindow()
        {
            InitializeComponent();

            discardChanges = false;

            var contact = new Contact("Dotnet9", "632871194@qq.com", "Dotnet9");
            hash = contact.GetHashCode();

            this.DataContext = contact;
        }

        private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            if (this.DataContext.GetHashCode() != hash && !discardChanges)
            {
                SnackbarUnsavedChanges.IsActive = true;
                e.Cancel = true;
            }
        }

        private void Button_Click(object sender, RoutedEventArgs e)
        {
            //保存数据
        }

        private void SnackbarMessage_ActionClick(object sender, RoutedEventArgs e)
        {
            SnackbarUnsavedChanges.IsActive = false;
            discardChanges = true;
            this.Close();
        }
    }
}

3.6 Contact.cs

联系人实体类

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Text;

namespace ValidateDataChange
{
    internal class Contact : INotifyPropertyChanged
    {
        public event PropertyChangedEventHandler PropertyChanged;
        private void NotifyPropertyChanged(string info)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(info));
            }
        }


        private string name;
        public string Name
        {
            get { return name; }
            set { name = value; NotifyPropertyChanged("Name"); }
        }
        private string email;
        public string Email
        {
            get { return email; }
            set { email = value; NotifyPropertyChanged("Email"); }
        }
        private string facebook;
        public string Facebook
        {
            get { return facebook; }
            set { facebook = value; NotifyPropertyChanged("Facebook"); }
        }

        public Contact(string name, string email, string facebook)
        {
            this.name = name;
            this.email = email;
            this.facebook = facebook;
        }

        public override int GetHashCode()
        {
            return (name + email + facebook).GetHashCode();
        }

    }
}