WPF MVVM+EF 增删改查 简单示例（一）

实现了那些功能，先看看效果图：

项目工程目录：

接下来开始具体的步骤：

第一步：在VS中新建工程

第二步：使用NuGet 安装EntityFramework

第三步：使用NuGet 安装EntityFramework.SqlSreverCompact

第四步：在Entities文件夹下添加StudentEntity类

  public class StudentEntity
     {
         public int StudentId { get; set; }
         public string StudentName { get; set; }
         public int StudentAge { get; set; }
         public int StudentSex { get; set; }
         public string StudentAddress { get; set; }

     }

第五步：在Mappings文件夹下添加实体映射StudentEntityMapping类

 public class StudentEntityMapping : EntityTypeConfiguration<StudentEntity>
    {
        public StudentEntityMapping()
        {
            this.HasKey(t => t.StudentId);

            this.ToTable("Student");

            this.Property(t => t.StudentId).HasColumnName("StudentId").HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity).IsRequired();
            this.Property(t => t.StudentName).HasColumnName("StudentName").HasColumnType(SqlDbType.NVarChar.ToString()).HasMaxLength().IsRequired();
            this.Property(t => t.StudentAge).HasColumnName("StudentAge").HasColumnType(SqlDbType.Int.ToString()).IsRequired();
            this.Property(t => t.StudentSex).HasColumnName("StudentSex").HasColumnType(SqlDbType.Int.ToString()).IsRequired();
            this.Property(t => t.StudentAddress).HasColumnName("StudentAddress").HasColumnType(SqlDbType.NVarChar.ToString()).HasMaxLength().IsRequired();
        }
    }

第六步：在Dal文件夹下添加StudentDataContext类

  public class StudentDataContext : DbContext
    {

        public StudentDataContext()
            : base("StudentDataContext")
        {

        }
        public DbSet<StudentEntity> Students { get; set; }
        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Configurations.AddFromAssembly(typeof(StudentDataContext).Assembly);
        }
    }

第七步：在AppConfig添加数据库的连接字符串

注意此处的路径必须为绝对路径

<connectionStrings>
<add name="StudentDataContext" providerName="System.Data.SqlServerCe.4.0" connectionString="Data Source=E:\Sample\DataBase\StudentDataContext.sdf" />
</connectionStrings>

第八步：在NuGet包管理器中打开“程序包管理器控制台”

第九步：生成Migrations文件并创建数据库

A,在打开的程序包管理器控制台中输入  enable-migrations 命令此时会自动在工程目录下创建一个Migrations文件夹和Configuration.cs

B,打开Configuration.cs 修改 AutomaticMigrationsEnabled = true;

C,在打开的程序包管理器控制台中输入update-database

D，执行完成后就会在E:\Sample\DataBase\StudentDataContext.sdf下创建好数据库，将此数据库包含在项目中并将其包含在项目中，并将其设置为始终复制，编译项目，

并再次修改App.Config中的连接字符串。connectionString="Data Source=DataBase\StudentDataContext.sdf"

第十步：在Dal下添加一个用于操作数据的类StudentDal

  public  class StudentDal
    {
        StudentDataContext studentDataContext = new StudentDataContext();

        public List<StudentEntity> GetAllStudent()
        {
            return studentDataContext.Students.ToList();
        }

        public void Insert(StudentEntity studentEntity)
        {
            studentDataContext.Students.Add(studentEntity);
            studentDataContext.SaveChanges();
        }
        public void Delete(StudentEntity studentEntity)
        {
            studentDataContext.Students.Remove(studentEntity);
            studentDataContext.SaveChanges();
        }
        public void Update(StudentEntity studentEntity)
        {
            var id = studentDataContext.Students.Find(studentEntity.StudentId);
            var entry = studentDataContext.Entry(id);
            entry.CurrentValues.SetValues(studentEntity);
            entry.Property(p => p.StudentId).IsModified = false;
            studentDataContext.SaveChanges();
        }
    }

第十一步：在Views文件加下添加AddOrEditWindow.xaml和StudentControl.xaml

StudentControl.xaml

<UserControl x:Class="Sample.Views.StudentControl"
             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:viewModel="clr-namespace:Sample.ViewModels"
             xmlns:convert="clr-namespace:Sample.Convert"
             mc:Ignorable="d" >
    <UserControl.Resources>
        <Style  TargetType="{x:Type DataGridColumnHeader}">
            <Setter Property="HorizontalContentAlignment" Value="Center" />
            <Setter Property="VerticalContentAlignment" Value="Center" />
        </Style>
        <convert:ConvertIntToString x:Key="convertIntToString" ></convert:ConvertIntToString>
    </UserControl.Resources>
    <UserControl.DataContext>
        <viewModel:StudentViewModel></viewModel:StudentViewModel>
    </UserControl.DataContext>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height=""></RowDefinition>
            <RowDefinition Height="*"></RowDefinition>
        </Grid.RowDefinitions>
        <Button Width="" Height="" Content="添加" HorizontalAlignment="Right" Margin="0,0,20,0" Grid.Row="" Command="{Binding AddCommand}"></Button>
        <Button Width="" Height="" Content="刷新" HorizontalAlignment="Right" Margin="0,0,120,0" Grid.Row="" Command="{Binding RefreshCommand}"/>
        <Rectangle Fill="Black" Height="" Grid.Row="" VerticalAlignment="Bottom"></Rectangle>
        <DataGrid Grid.Row="" ItemsSource="{Binding Students}"  SelectedItem="{Binding SelectStudentEntity, Mode=TwoWay}"  CanUserSortColumns="False"  CanUserResizeColumns="False" CanUserResizeRows="False" SelectionMode="Extended"
                            CanUserReorderColumns="False"  RowHeaderWidth="" CanUserAddRows="False"  AutoGenerateColumns="False"  EnableRowVirtualization="False" GridLinesVisibility="None"  Margin="" >
            <DataGrid.Columns>
                <DataGridTemplateColumn Header="编号" Width="" >
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Grid>
                                <TextBlock Text="{Binding StudentId}" HorizontalAlignment="Center" VerticalAlignment="Center" ></TextBlock>
                            </Grid>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
                <DataGridTemplateColumn Header="姓名" Width="" >
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Grid>
                                <TextBlock Text="{Binding StudentName}" HorizontalAlignment="Center" VerticalAlignment="Center" ></TextBlock>
                            </Grid>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
                <DataGridTemplateColumn Header="性别" Width="" >
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Grid>
                                <TextBlock Text="{Binding StudentSex,Converter={StaticResource convertIntToString}}" HorizontalAlignment="Center" VerticalAlignment="Center" ></TextBlock>
                            </Grid>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
                <DataGridTemplateColumn Header="年龄" Width="" >
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Grid>
                                <TextBlock Text="{Binding StudentAge}" HorizontalAlignment="Center" VerticalAlignment="Center" ></TextBlock>
                            </Grid>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
                <DataGridTemplateColumn Header="家庭住址" Width="" >
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Grid>
                                <TextBlock Text="{Binding StudentAddress}" HorizontalAlignment="Center" VerticalAlignment="Center" ></TextBlock>
                            </Grid>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
                <DataGridTemplateColumn  Width="" Header="操作">
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Grid>
                                <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center">

                                    <Button    Width="" Height="" Content="编辑"   FontSize=""   Command="{Binding DataContext.EditCommand, RelativeSource={RelativeSource Mode=FindAncestor,AncestorType=UserControl}}"  ></Button>
                                    <Button    Width="" Height=""  Margin="10,0,0,0" Content="删除" FontSize="" Command="{Binding DataContext.DeleteCommand, RelativeSource={RelativeSource Mode=FindAncestor,AncestorType=UserControl}}" ></Button>
                                </StackPanel>
                            </Grid>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
            </DataGrid.Columns>
        </DataGrid>

    </Grid>
</UserControl>

AddOrEditWindow.xaml

 <Window x:Class="Sample.Views.AddOrEditWindow"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:viewModel="clr-namespace:Sample.ViewModels"
         Title="AddOrEditWindow" Height="" Width="" WindowStartupLocation="CenterScreen" Topmost="True" ResizeMode="NoResize">
     <Window.DataContext>
         <viewModel:AddOrEditViewModel></viewModel:AddOrEditViewModel>
     </Window.DataContext>
     <Grid>
         <Grid.RowDefinitions>
             <RowDefinition Height=""></RowDefinition>
             <RowDefinition Height=""></RowDefinition>
             <RowDefinition Height=""></RowDefinition>
             <RowDefinition Height=""></RowDefinition>
             <RowDefinition Height="*"></RowDefinition>
         </Grid.RowDefinitions>
         <Grid.ColumnDefinitions>
             <ColumnDefinition Width=""></ColumnDefinition>
             <ColumnDefinition Width="*"></ColumnDefinition>
         </Grid.ColumnDefinitions>
         <Label Grid.Row="" Grid.Column="" Content="学生姓名:" HorizontalAlignment="Right" VerticalAlignment="Center" Margin="0,0,10,0"></Label>
         <Label Grid.Row="" Grid.Column="" Content="学生年龄:" HorizontalAlignment="Right" VerticalAlignment="Center" Margin="0,0,10,0"></Label>
         <Label Grid.Row="" Grid.Column="" Content="学生性别:" HorizontalAlignment="Right" VerticalAlignment="Center" Margin="0,0,10,0"></Label>
         <Label Grid.Row="" Grid.Column="" Content="家庭住址:" HorizontalAlignment="Right" VerticalAlignment="Center" Margin="0,0,10,0"></Label>
         <TextBox Grid.Row="" Grid.Column="" Width="" Height="" Text="{Binding CurrentStudentEntity.StudentName,Mode=TwoWay}"></TextBox>
         <TextBox Grid.Row="" Grid.Column="" Width="" Height="" Text="{Binding CurrentStudentEntity.StudentAge,Mode=TwoWay}"></TextBox>
         <StackPanel Orientation="Horizontal" Grid.Row="" Grid.Column="" Margin="20,0,0,0">
             <RadioButton  GroupName="sex"  Content="男" VerticalAlignment="Center" IsChecked="{Binding IsChecked,Mode=TwoWay}"></RadioButton>
             <RadioButton  GroupName="sex"   Content="女" VerticalAlignment="Center"  Margin="20,0,0,0"></RadioButton>
         </StackPanel>
         <TextBox Grid.Row="" Grid.Column="" Width="" Height="" Text="{Binding CurrentStudentEntity.StudentAddress,Mode=TwoWay}"></TextBox>
         <Rectangle Grid.Row="" Grid.Column="" Grid.ColumnSpan="" Fill="Black" Height="" VerticalAlignment="Bottom"></Rectangle>
         <Button Content="保存" Width="" Height="" Grid.Row="" Grid.Column="" Command="{Binding SaveCommand}"></Button>
     </Grid>
 </Window>

第十二步：在ViewModels中添加AddOrEditViewModel.cs和StudentViewModel.cs

StudentViewModel.cs代码：

 public class StudentViewModel : ViewModelBase
    {
        private List<StudentEntity> _students;
        public List<StudentEntity> Students
        {
            get { return _students; }
            set
            {
                if (_students != value)
                {
                    _students = value;
                    this.OnPropertyChanged(r => r.Students);
                }
            }
        }

        private StudentEntity _studentEntity;
        public StudentEntity SelectStudentEntity
        {
            get { return _studentEntity; }
            set
            {
                if (_studentEntity != value)
                {
                    _studentEntity = value;
                    this.OnPropertyChanged(r => r.SelectStudentEntity);
                }
            }
        }

        public ICommand AddCommand { get; set; }
        public ICommand RefreshCommand { get; set; }
        public ICommand EditCommand { get; set; }
        public ICommand DeleteCommand { get; set; }

        private StudentDal studentDal = null;
        public StudentViewModel()
        {
            studentDal = new StudentDal();
            AddCommand = new DelegateCommand(AddStuddent);
            RefreshCommand = new DelegateCommand(Refresh);
            EditCommand = new DelegateCommand(EditStudent);
            DeleteCommand = new DelegateCommand(DeleteStudent);
            Students = new  List<StudentEntity>();
            Students = studentDal.GetAllStudent();
        }

        private void AddStuddent()
        {
            AddOrEditWindow addOrEditWindow = new AddOrEditWindow();
            addOrEditWindow.Show();
            var addOrEditViewModel = (addOrEditWindow.DataContext as AddOrEditViewModel);
            addOrEditViewModel.CurrentStudentEntity = new StudentEntity();
            addOrEditViewModel.IsAdd = true;
            addOrEditViewModel.StudentDal = studentDal;
        }

        private void Refresh()
        {
            Students = studentDal.GetAllStudent();
        }
        private void EditStudent()
        {
           AddOrEditWindow  addOrEditWindow = new AddOrEditWindow();
           addOrEditWindow.Show();
           var addOrEditViewModel = (addOrEditWindow.DataContext as AddOrEditViewModel);
           addOrEditViewModel.CurrentStudentEntity = SelectStudentEntity;
           addOrEditViewModel.IsAdd = false;
           addOrEditViewModel.StudentDal = studentDal;
        }

        private void DeleteStudent()
        {
            studentDal.Delete(SelectStudentEntity);
        }

    }

AddOrEditViewModel.cs代码：

 public class AddOrEditViewModel :ViewModelBase

        private StudentEntity _currentStudentEntity;
        public StudentEntity CurrentStudentEntity
        {
            get { return _currentStudentEntity; }
            set
            {
                if (_currentStudentEntity != value)
                {
                    _currentStudentEntity = value;
                    if (_currentStudentEntity.StudentSex == )
                    {
                        IsChecked = true;
                    }
                    else
                    {
                        IsChecked = false ;
                    }

                    this.OnPropertyChanged(r => r.CurrentStudentEntity);
                }
            }
        }

        private bool _isChecked;
        public bool IsChecked
        {
            get { return _isChecked; }
            set
            {
                if (_isChecked != value)
                {
                    _isChecked = value;
                    this.OnPropertyChanged(r => r.IsChecked);
                }
            }
        }

        public StudentDal StudentDal { get; set; }

        private bool _isAdd = false;

        public bool IsAdd
        {
            get { return _isAdd; }
            set
            {
                if (_isAdd != value)
                {
                    _isAdd = value;
                    this.OnPropertyChanged(r => r.IsAdd);
                }
            }
        }
        public ICommand SaveCommand { get; set; }

        public AddOrEditViewModel()
        {
            SaveCommand = new DelegateCommand(Save);
        }

        private void Save()
        {
            StudentEntity student = new StudentEntity();
            student.StudentName = CurrentStudentEntity.StudentName;
            student.StudentAge = CurrentStudentEntity.StudentAge;
            student.StudentSex = IsChecked ?:;
            student.StudentAddress = CurrentStudentEntity.StudentAddress;
            if (IsAdd)
            {
                StudentDal.Insert(student);
            }
            else
            {
                student.StudentId = CurrentStudentEntity.StudentId;
                StudentDal.Update(student);
            }
        }
    }

至于ViewModelBase.cs和DelegateCommand.cs这两个类可以在网上查查，这里就不贴了。

第十三步:对于性别的转换单独写了一个转化器ConvertIntToString.cs其主要功能是将数据库中的0和1转换为 “男”和“女”显示

[System.Windows.Data.ValueConversion(typeof(int), typeof(string))]
    public class ConvertIntToString : System.Windows.Data.IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            string sex="";
            if (int.Parse(value.ToString()) == )
            {
                sex = "男";
            }
            else
            {
                sex = "女";
            }
            return sex;
        }

        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }

第十四步：在MainWindow.xaml中添加StudentControl控件

此文仅作学习中的记录，希望对看到此文的同学有一点点的帮助。

文中如果有不正确的地方欢迎指正。