C# WPF ComboBox 绑定到 ObservableCollection

WPF ComboBox Binding to ObservableCollection

提问by MentalBrake

I'm new to WPF And I have a question. I have the Organization module:

我是 WPF 的新手 我有一个问题。我有组织模块：

class Organization : ObservableObject
{
    public string OrganizationName { get; set; }
}

I have the ViewModel of the Organization:

我有组织的 ViewModel：

class OrganizationViewModel : ObservableObject
{
    int _count = 0;

    public OrganizationViewModel()
    {
        Organization = new Organization {OrganizationName = "New Organization"};
    }

    public Organization Organization { get; set; }

    public string OrganizationName
    {
        get { return Organization.OrganizationName; }
        set
        {
            if(Organization.OrganizationName != value)
            {
                Organization.OrganizationName = value;
                RaisePropertyChanged("OrganizationName");
            }
        }
    }

And I have the ViewModel of all the Organizations:

我有所有组织的 ViewModel：

class AllOrganizationsViewModel
    {
        private ObservableCollection<OrganizationViewModel> m_organizations = new ObservableCollection<OrganizationViewModel>();


    public ObservableCollection<OrganizationViewModel> Organizations
    {
        get { return m_organizations; }
        set { m_organizations = value; }
    }

    public AllOrganizationsViewModel()
    {
        for(int i = 0; i < 3; ++i)
        {
            m_organizations.Add(new OrganizationViewModel());
        }
    }

    void AddOrganizationNameExecute()
    {
        m_organizations.Add(new OrganizationViewModel());
    }

    bool CanAddOrganizationNameExecute()
    {
        return true;
    }

    public ICommand AddOrganization{get{return new RelayCommand(AddOrganizationNameExecute, CanAddOrganizationNameExecute);}}

}

And this is the MainWindow.xaml:

这是 MainWindow.xaml：

<Window x:Class="DataIntegrityChecker.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:DataIntegrityChecker.ViewModels" Title="MainWindow" Height="350" Width="525">
    <Window.DataContext>
        <local:AllOrganizationsViewModel />
    </Window.DataContext>
    <Grid>
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto" />
            <RowDefinition Height="285*" />
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="156" />
            <ColumnDefinition Width="347*" />
        </Grid.ColumnDefinitions>
        <Label Content="Organization: " Margin="0,0,44,0" />
        <Button Grid.Row="1" Name="UpdateOrganizations" Content="Update Organization Name" Command="{Binding AddOrganization}" Margin="0,0,0,262" HorizontalAlignment="Left" Width="156" />
        <ComboBox Grid.Column="1" Grid.Row="1" Height="23" HorizontalAlignment="Left" Name="comboBox1" VerticalAlignment="Top" Width="155"  ItemsSource="{Binding Organizations}" />
    </Grid>
</Window>

Now, what I get in the ComboBox items is the name of the class OrganizationViewModel but what I need is the OrganizationName string. It seems to me that I have some binding to OrganizationName that's missing but I can't figure out where to add if (if that's the issue). I assume I can make a collection of strings with the names of the organizations I need. But in the future I will need more properties in the Organization Class so that's the way I need it to work.

现在，我在 ComboBox 项中得到的是类 OrganizationViewModel 的名称，但我需要的是 OrganizationName 字符串。在我看来，我缺少一些与 OrganizationName 的绑定，但我不知道在哪里添加 if（如果这是问题的话）。我假设我可以用我需要的组织的名称制作一个字符串集合。但是将来我将需要组织类中的更多属性，所以这就是我需要它工作的方式。

I will appreciate any help

我将不胜感激任何帮助

采纳答案by Vyacheslav Volkov

You need to add DisplayMemberPath:

您需要添加DisplayMemberPath：

<ComboBox Grid.Column="1" Grid.Row="1" Height="23" HorizontalAlignment="Left" Name="comboBox1" VerticalAlignment="Top" Width="155"  ItemsSource="{Binding Organizations}"
          DisplayMemberPath="OrganizationName"/>

回答by Rohit Agrawal

Another way can be by defining ItemTemplate. It gives more flexibility on display

另一种方法是定义 ItemTemplate。它在显示上提供了更大的灵活性

   <ComboBox Grid.Column="1" Grid.Row="1" Height="23" HorizontalAlignment="Left" Name="comboBox1" VerticalAlignment="Top" Width="155"  ItemsSource="{Binding Organizations}" >
        <ComboBox.ItemTemplate>
            <DataTemplate>
                <TextBlock Text="{Binding OrganizationName}"/>
            </DataTemplate>
        </ComboBox.ItemTemplate>
    </ComboBox>