两个表的Wpf DatagridComboBoxColumn绑定？

Question

我必须去书籍和出版社上课：

public partial class Books
{
    public Books()
    {
        this.Authors = new ObservableCollection<Authors>();
    }

    public int bID { get; set; }
    public string Title { get; set; }
    public int phID { get; set; }
    public Nullable<short> PubYear { get; set; }
    public Nullable<short> Edition { get; set; }

    public virtual PublishingHouse PublishingHouse { get; set; }
    public virtual ObservableCollection<Authors> Authors { get; set; }
}
public partial class PublishingHouse
{
    public PublishingHouse()
    {
        this.Books = new ObservableCollection<Books>();
    }

    public int phID { get; set; }
    public string Title { get; set; }
    public string City { get; set; }    

    public virtual ObservableCollection<Books> Books { get; set; }
}

所以我有 Datagrid，它显示了我所有的书：

<Window.Resources>
    <CollectionViewSource x:Key="booksViewSource" d:DesignSource="{d:DesignInstance {x:Type local:Books}, CreateList=True}"/>
    <CollectionViewSource x:Key="booksAuthorsViewSource" Source="{Binding Authors, Source={StaticResource booksViewSource}}"/>
    <CollectionViewSource x:Key="authorsViewSource" d:DesignSource="{d:DesignInstance {x:Type local:Authors}, CreateList=True}"/>
    <CollectionViewSource x:Key="publishingHouseViewSource" d:DesignSource="{d:DesignInstance {x:Type local:PublishingHouse}, CreateList=True}"/>
</Window.Resources>
<Grid DataContext="{StaticResource booksViewSource}" Margin="0,0,2,0">
    <DataGrid ItemsSource="{Binding}">
        <DataGrid.Columns>
            <DataGridTextColumn Header="b ID" Binding="{Binding bID}"/>
            <DataGridTextColumn Header="Title" Binding="{Binding Title}"/>
            <DataGridTextColumn Header="#" Binding="{Binding Edition}"/>
            <DataGridTextColumn Header="Year" Binding="{Binding PubYear}"/>
            <DataGridComboBoxColumn x:Name="phIDComboBoxColumn" SelectedItemBinding="{Binding phID}" />
        </DataGrid.Columns>
    </DataGrid>

我想要的是将我的phIDComboBoxColumn 的默认值设置为取自一本书，但是当我想编辑它时，我想查看所有可用@ 的phId 列表987654325@。我必须以某种方式为两个数据源绑定“DataGridComboBoxColumn”吗？

Answer 1

您的Book 类应该有一个Property，其中包含所有可用PublishingHouses 的phId's 列表，如下所示：

public ObservableCollection<int> PhIdList {get; set;}

那么你的DataGridComboBoxColumn 会变成这样：

<DataGridComboBoxColumn Header="PhIDs" SelectedItemBinding="{Binding phID}">
    <DataGridComboBoxColumn.ElementStyle>
        <Style TargetType="ComboBox">
            <Setter Property="ItemsSource" Value="{Binding PhIdList}"/>
            <Setter Property="IsReadOnly" Value="True"/>
        </Style>
    </DataGridComboBoxColumn.ElementStyle>
    <DataGridComboBoxColumn.EditingElementStyle>
        <Style TargetType="ComboBox">
            <Setter Property="ItemsSource" Value="{Binding PhIdList}"/>
        </Style>
    </DataGridComboBoxColumn.EditingElementStyle>
</DataGridComboBoxColumn>

编辑

如果这样做，Book 的每个对象都将包含相同的可用 PublishingHouse 集合。这对记忆来说是非常低效的。有其他解决办法吗？

为了防止数据冗余，您可以在 父类 中定义 PhIdList（例如，如果您使用 mvvm，则为书籍列表容器视图模型）并获取 ComboBox 数据，如下所示：

            <DataGridComboBoxColumn 
                SelectedItemBinding="{Binding phID}" DisplayMemberPath="" >
                <DataGridComboBoxColumn.ElementStyle>
                    <Style TargetType="{x:Type ComboBox}">
                        <Setter Property="ItemsSource" Value="{Binding Path=DataContext.BooksContainerVM.PhIdList, RelativeSource={RelativeSource AncestorType={x:Type Window}}}" />
                    </Style>
                </DataGridComboBoxColumn.ElementStyle>
                <DataGridComboBoxColumn.EditingElementStyle>
                    <Style TargetType="{x:Type ComboBox}">
                        <Setter Property="ItemsSource" Value="{Binding Path=DataContext.BooksContainerVM.PhIdList, RelativeSource={RelativeSource AncestorType={x:Type Window}}}" />
                    </Style>
                </DataGridComboBoxColumn.EditingElementStyle>
            </DataGridComboBoxColumn>