Cfrgtkky

I have classes

[Table(Name = "Categories")]

class Category

{

    [Column(Name = "CategoryID", IsPrimaryKey = true, IsDbGenerated = true)]

    private int CategoryID { get; set; }

    [Column(Name = "Name")]

    public string Name { get; set; }

}



[Table(Name = "Products")]

class Product

{

    [Column(Name = "ProductID", IsPrimaryKey = true, IsDbGenerated = true)]

    public int ProductID { get; set; }

    [Column(Name = "CategoryID")]

    public int CategoryID { get; set; }

    [Column(Name = "Name")]

    public string Name { get; set; }

    [Column(Name = "Price")]

    public double Price { get; set; }

}

and i need to create DataGrid column as ComboBox using CategoryID from Products and put all categories in ComboBox from Categories for editing, how can i make it with using DataContext

Here I have created ObservableCollection of Product and Category with name ProductSet & ListOfCategory in the Window level.

public ObservableCollection<Category> ListOfCategory { get; set; }

public ObservableCollection<Product> ProductSet  { get; set; }

I have created both the ObservableCollection in the Code behind of the Window, You can create this in view model which is better approch.

I have named the Window as "Window1" x:Name="Window1"

As you need to bind the data context, did the elementBinding with Window1 and also set the ItemsSource="{Binding ProductSet}". So what happens here is the ProuctSet is searched for DataContext, which is in turn searched inside Window1 Class.

For DataGridComboBoxColumn, set the ItemsSource using the Style and search for the Datagrid DataContext which has ListOfCategory using Relative Source.

<DataGrid AutoGenerateColumns="False" x:Name="DataGrid1" HorizontalAlignment="Left" Height="135" Margin="21,288,0,0" VerticalAlignment="Top" Width="729" DataContext="{Binding ElementName=Window1}" ItemsSource="{Binding ProductSet}" >

    <DataGrid.Columns>

        <DataGridTextColumn Header="ProductID" Width="175" Binding="{Binding ProductID}"></DataGridTextColumn>

            <DataGridComboBoxColumn   Header="Category"    DisplayMemberPath="Name" SelectedValuePath="CategoryID" SelectedItemBinding="{Binding ListOfCategory}">

                <DataGridComboBoxColumn.ElementStyle>

                    <Style TargetType="ComboBox">

                        <Setter Property="ItemsSource" Value="{Binding Path=DataContext.ListOfCategory, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type DataGrid}}}" />

                    </Style>

                </DataGridComboBoxColumn.ElementStyle>

                <DataGridComboBoxColumn.EditingElementStyle>

                        <Style TargetType="ComboBox">

                        <Setter Property="ItemsSource" Value="{Binding Path=DataContext.ListOfCategory,RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type DataGrid}}}" />

                    </Style>

                    </DataGridComboBoxColumn.EditingElementStyle>

    </DataGridComboBoxColumn>

        <DataGridTextColumn Header="Name" Width="175" Binding="{Binding Name}"></DataGridTextColumn>

        <DataGridTextColumn Header="Price " Width="175" Binding="{Binding Price }"></DataGridTextColumn>

    </DataGrid.Columns>

</DataGrid>

If you going to bind using View model, then provide the Class Name of the Viewmodel instead of Element Binding.