5

我的 UI 上显示了两个数据网格。当我在数据网格 1 上选择特定行时,我想在数据网格 2 上显示数据网格 1 的详细信息。我正在从数据库中填充数据网格数据。这里是两个数据库表结构。

注意:这两个表都是由数据库中的personid映射的

人表

人员详细信息表

这是到目前为止我尝试过的代码

基类.cs

public class Baseclass
{
    public event PropertyChangedEventHandler PropertyChanged;

    protected void SetProperty<T>(ref T member, T value, [CallerMemberName] string propertyName = null)
    {
        member = value;
        this.RaiseNotification(propertyName);
    }

    protected void RaiseNotification(string propertyName)
    {
        if (this.PropertyChanged != null)
        {
            this.PropertyChanged.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
}

个人.cs

public class person : Baseclass
{

    private int personID;
    public int PersonID
    {
        get { return personID; }
        set { this.SetProperty<int>(ref this.personID, value); }
    }

    private string firstName;
    public string FirstName
    {
        get { return firstName; }
        set { this.SetProperty<string>(ref this.firstName, value); }
    }

    private string lastName;
    public string LastName
    {
        get { return lastName; }
        set { this.SetProperty<string>(ref this.lastName, value); }
    }

    Model _personModel = new Model();
    private ObservableCollection<person> _person = new ObservableCollection<person>();
    public ObservableCollection<person> Getpersons
    {
        get { return _person; }
        set { _person = value; OnPropertyChanged("GetPersons"); }
    }

    public person()
    {
        initializeload();
    }

    private void initializeload()
    {
        try
        {
            DataTable table = _personModel.getData();

            for (int i = 0; i < table.Rows.Count; ++i)
                Getpersons.Add(new person
                {
                 PersonID = Convert.ToInt32(table.Rows[i][0]),
                 FirstName = table.Rows[i][1].ToString(),
                 LastName = table.Rows[i][2].ToString(),
                });
        }

        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }
    }
    public event PropertyChangedEventHandler PropertyChanged;

    private void OnPropertyChanged(string propertyname)
    {
        var handler = PropertyChanged;
        if (handler != null)
            handler(this, new PropertyChangedEventArgs(propertyname));
    }

    public class Model
    {
        public DataTable getData()
        {
            DataTable ndt = new DataTable();
            SqlConnection sqlcon = new SqlConnection(ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString);
            sqlcon.Open();
            SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM [Person].[dbo].[persons]", sqlcon);
            da.Fill(ndt);
            da.Dispose();
            sqlcon.Close();
            return ndt;
        }
    }

}

PersonDetail 类

public  class PersonDetails : Baseclass
{
    private int personID;
    public int PersonID
    {
        get { return personID; }
        set { this.SetProperty<int>(ref this.personID, value); }
    }

    private string address;
    public string Address
    {
        get { return address; }
        set { this.SetProperty<string>(ref this.address, value); }
    }

    private string pos;
    public string Position
    {
        get { return pos; }
        set { this.SetProperty<string>(ref this.pos, value); }
    }

    DetailsModel _detailModel = new DetailsModel();
    private ObservableCollection<PersonDetails> _details = new ObservableCollection<PersonDetails>();
    public ObservableCollection<PersonDetails> GetDetails
    {
        get { return _details; }
        set { _details = value; OnPropertyChanged("GetDetails"); }
    }
    public event PropertyChangedEventHandler PropertyChanged;

    private void OnPropertyChanged(string propertyname)
    {
        var handler = PropertyChanged;
        if (handler != null)
            handler(this, new PropertyChangedEventArgs(propertyname));
    }

    public PersonDetails()
    {
        initializeload();
    }

    private void initializeload()
    {
        try
        {
            DataTable table = _detailModel.getData();

            for (int i = 0; i < table.Rows.Count; ++i)
                GetDetails.Add(new PersonDetails
                {
                    PersonID = Convert.ToInt32(table.Rows[i][0]),
                    Address = table.Rows[i][1].ToString(),
                    Position = table.Rows[i][2].ToString(),                        
                });
        }

        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }
    }
    public class DetailsModel
    {
        public DataTable getData()
        {
            DataTable ndt = new DataTable();
            SqlConnection sqlcon = new SqlConnection(ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString);
            sqlcon.Open();
            SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM [Person].[dbo].[personDetails]", sqlcon);
            da.Fill(ndt);
            da.Dispose();
            sqlcon.Close();
            return ndt;
        }
    }
}

主视图模型.cs

    public class MainViewModel : Base, INotifyPropertyChanged
{
    public MainViewModel()
    {
    }

    private ObservableCollection<person> personValues;
    public ObservableCollection<person> Persons
    {
        get { return personValues; }
        set
        {
            this.SetProperty<ObservableCollection<person>>(ref this.personValues, value);
        }
    }

    private ObservableCollection<PersonDetails> detailsValues;
    public ObservableCollection<PersonDetails> Details
    {
        /* This is correct below ?? I have an error as 
        'PersonDemo.MainViewModel' does not contain a definition for 'GetDetails' and no extension method 'GetDetails' accepting a first argument of type 'PersonDemo.MainViewModel' could be found (are you missing a using directive or an assembly reference?)*/
        get { return this.GetDetails(this.Selectedperson.PersonID); }
    }

    private person selectedValue;
    public person Selectedperson
    {
        get { return selectedValue; }
        set
        {
            this.SetProperty<person>(ref this.selectedValue, value);
            this.RaiseNotification("Details");
        }
    }


}

XAML

  <Grid>
  <DataGrid Margin="100,20,116,211" ItemsSource="{Binding Persons}" SelectedItem="{Binding Selectedperson}"  />
  <DataGrid Margin="100,130,116,101" ItemsSource="{Binding Details}" />
  </Grid>

任何人都可以帮助继续编写 MainViewModel 吗?几个星期以来我都被困在这里。

4

2 回答 2

7

首先,我建议使用INotifyPropertyChanged基类中的接口。也许您使用它并忘记在示例代码中编写它。为了使用 MVVM 模式实现这一点,您需要为两个数据网格实现一个 ViewModel。让我们在我们的示例BothGridViewModel中调用它,您可以随意调用它。然后在这个视图模型中你需要所有人的集合,我们称之为它AllPerson,然后你需要有一个Person类型的属性,当你在网格中有选定的人时,我们称之为它SelectedPerson。它会是这样的:

public class BothGridViewModel:INotifyPropertyChanged
{
    ...
    public ObservableCollection<Person> AllPersons {...}
    public Person SelectedPerson {...}
    ...
}

您只需要在 View 的 DataContext 中设置它。和绑定:

<YourView DataContext={Binding SomeBothGridViewModelClass}>
    <Grid>
     <DataGrid Margin="100,20,116,211" ItemsSource="{Binding AllPersons}" SelectedItem="{Binding SelectedPerson}"  />
     <DataGrid Margin="100,130,116,101" ItemsSource="{Binding SelectedPerson.Getpersons}" /> <!--Or some SelectedPerson.PersonDetails.GetDetails-->
  </Grid>
</YourView DataContext={Binding SomeBothGridViewModelClass}>

我认为这是制作您想要的东西的良好视图模型结构。希望这可以帮助你...


编辑


我现在明白你的意思了,你有两个数据库表,一个用于主要属性,另一个用于详细信息。我看到了这样做的两种好方法:1)第一种方法是,我不相信第二个数据网格对于每个没有详细信息集合的人都是必要的。相反,您可以使用网格和其他控件来显示属性。另外我认为你必须为这个人实现一个视图模型,例如:

public class PersonViewModel:INotifyPropertyChanged
{
     public string FirstName {...}
     public string LastName {...}
     //Other properties

     public PersonDetails Details {...}
}

然后在网格中,您可以将项目源绑定到一个集合,PersonViewModel然后您可以绑定到网格的选定项目,例如:

<Grid>
    <DataGrid x:Name="dataGrid" ItemsSource={Binding AllPersonViewModels}/>
    ...
    <!--Then some combo box, text block or text box binding to a property of the selected item's details-->
          ...
          <TextBox Text={Binding SelectedItem.Details.Address, ElementName=dataGrid}/>
          ...
<Grid>

2)我认为可以完成的第二种方法是在同一个数据网格中显示所有数据。为此,您需要以PersonViewModel这种方式上课:

public class PersonViewModel:INotifyPropertyChanged
{
     public string FirstName {...}
     public string LastName {...}
     //Other properties

     //Then the Details properties
     public string Address {...}
     //...
     //Note this class is like a wrapper for person, and person details
}

这种方式稍微简单一些,但可能会导致不需要的数据库过度访问。


编辑 2


在看了你的代码之后,我不得不说几件事:在PersonViewModelandPersonDetailViewModel你应该使用 aDispatcherTimer而不是 a Timer,因为我们在 Wpf 中。另一件事,也许您应该使用存储库模式来创建一个PersonRepository和一个PersonDetailRepository放置所有数据库通信的位置,实际上,PersonViewModel并且PersonDetailViewModel在某种程度上是一个存储库,但是现在您不需要更改它,它应该工作。我将在这里向您展示 的代码MainViewModel,我将其修改为具有 SelectedPersonDetail 属性,这样,您所需要做的就是在 View 中进行绑定:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using tryout13022013.PersonViewModels;
using System.ComponentModel;
using tryout13022013.DetailsViewModel;
using tryout13022013.PersonModel;

namespace tryout13022013
{
    public class MainViewModel
    {
        private PersonViewModel _subPerson = new PersonViewModel();
        public PersonViewModel SubPerson
        {
            get 
            {
                return _subPerson;
            }
            set
            {
                if (_subPerson != value)
                {
                    _subPerson = value; OnPropertyChanged("SubPerson");

                }
            }
        }


        private PersonDetailsViewModel _subDetail = new PersonDetailsViewModel();
        public PersonDetailsViewModel SubDetail
        {
            get { return _subDetail; }
            set 
            {
                _subDetail = value; OnPropertyChanged("SubDetail");
            }

        }

        private Person _selectedPerson;
        public Person SelectedPerson
        {
            get { return _selectedPerson; }
            set {
                if (_selectedPerson != value)
                {
                    _selectedPerson = value;
                    OnPropertyChanged("SelectedPerson");
                    OnPropertyChanged("SelectedPersonDetail");  //In this way when Change the Selected Person, the Selected Detail will be changed again...
                    //if (this.SelectedPerson != null && this.SubDetail != null)
                    //{
                       // I dont know how to call the PersonDetailsViewModel class like a method here in order to load its data. kindly help
                       //this.SubDetail.MethodforLoadingPersonDetails(this.SelectedPerson);
                    //}
                }
            }

        }

        public PersonDetails SelectedPersonDetail
        {
            get
            {
                if (SubDetail == null || SelectedPerson ==null)
                    return  null;
                return SubDetails.DetailsData.FirstOrDefault(detail => detail.PersonID == SelectedPerson.PersonID);
            }           

        }


        public event PropertyChangedEventHandler PropertyChanged;

        private void OnPropertyChanged(string propertyname)
        {
            var handler = PropertyChanged;
            if (handler != null)
                handler(this, new PropertyChangedEventArgs(propertyname));
        }
    }
}

这是您可以在视图中进行的绑定的一个实例,在这种情况下用于选择第二个网格中的项目:

<Window x:Class="tryout13022013.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:person="clr-namespace:tryout13022013.PersonViewModels"
    xmlns:details="clr-namespace:tryout13022013.DetailsViewModel"
    Title="MainWindow" Height="350" Width="525">
<Grid>
    <DataGrid ItemsSource="{Binding SubPerson.PersonData}"  SelectedItem="{Binding SelectedPerson, Mode=TwoWay}"
        AutoGenerateColumns="False" Height="77" HorizontalAlignment="Left"
        Margin="101,26,0,0" Name="dataGrid1" VerticalAlignment="Top" Width="auto" >
        <DataGrid.DataContext>
            <person:PersonViewModel/>
        </DataGrid.DataContext>
        <DataGrid.Columns>
            <DataGridTextColumn Header="ID" Width="auto" Binding="{Binding PersonID}"/>
            <DataGridTextColumn Header="First Name" Width="auto" Binding="{Binding FirstName}"/>
            <DataGridTextColumn Header="Last Name" Width="auto" Binding="{Binding LastName}"/>     
        </DataGrid.Columns>
    </DataGrid>


    <DataGrid ItemsSource="{Binding SubDetail.DetailsData}" 
        AutoGenerateColumns="False" Height="77" HorizontalAlignment="Left" 
        Margin="101,135,0,0" Name="dataGrid2" VerticalAlignment="Top" Width="255" SelectedItem="{Binding SelectedPersonDetail, Mode=OneWayToSource}">
        <DataGrid.DataContext>
            <details:PersonDetailsViewModel/>
        </DataGrid.DataContext>
        <DataGrid.Columns>
            <DataGridTextColumn Header="ID" Width="auto" Binding="{Binding PersonID}"/>
            <DataGridTextColumn Header="Address" Width="auto" Binding="{Binding Address}"/>
            <DataGridTextColumn Header="Position" Width="auto" Binding="{Binding Description}"/>
        </DataGrid.Columns>
    </DataGrid>
</Grid>

我忘记了,你需要绑定到SubPerson.PersonDataand SubDetail.DetailsData,这些是集合。一探究竟...

于 2013-02-11T19:58:10.127 回答
4

Having had a chat with Buba1947 in WPF room, I've concluded that she's actually got a 1-1 relation split table in database that she's actually trying to show as such in the split data grids.

I've proposed her to create a PersonViewModel on top of Person & PersonDetails tables so her MainViewModel contains only one ObservableCollection<PersonViewModel> under the Persons property to which we shall bind the two DataGrids.

so MainViewModel.cs (the DataContext) has:

private ObservableCollection<PersonViewModel> personValues; 
public ObservableCollection<PersonViewModel> Persons 
{ 
    get { return personValues; } 
    set { this.SetProperty<ObservableCollection<PersonViewModel>>(ref this.personValues, value); } 
} 

The data adaptor is changed to bring the data in using an inner join with relevant query being something along the lines of this (which fills the Persons property above):

"SELECT * FROM [Person].[dbo].[persons] INNER JOIN [Person].[dbo].[personDetails] ON [Person].[dbo].[persons].[Id] = [Person].[dbo].[personDetails].[Id]"

Next we shall bind a CollectionViewSource to Persons in Xaml:

<Window.Resources>
    <CollectionViewSource x:Key="PersonsData" Source={Binding Persons} />
</Window.Resources>

and bind DataGrids to this with individual columns:

<DataGrid ItemsSource={Binding Source={StaticResource PersonsData}} AutoGenerateColumns="false">
    <DataGrid.Columns>
        <DataGridTextColumn Header="Person Id" Content={Binding PersonId} />
        <DataGridTextColumn Header="First Name" Content={Binding FirstName} />
        <DataGridTextColumn Header="Last Name" Content={Binding LastName} />
    </DataGrid.Columns>
</DataGrid>

<DataGrid ItemsSource={Binding Source={StaticResource PersonsData}} AutoGenerateColumns="false">
    <DataGrid.Columns>
        <DataGridTextColumn Header="Person Id" Content={Binding PersonId} />
        <DataGridTextColumn Header="Address" Content={Binding Address} />
        <DataGridTextColumn Header="Position" Content={Binding Position} />
    </DataGrid.Columns>
</DataGrid>

Note: there may be typo in here as I haven't got VS to hand, please let me know if I need to fix something. I've written all of this from memory.

于 2013-02-12T11:51:40.307 回答