Добавление значений из ComboBox в DataGrid в WPF

В основном обратите внимание на привязку:

<DataGrid x:Name = "DataGridInvoices" ItemsSource = "{Binding}"  Height = "236" Width = "636" AutoGenerateColumns = "False" CanUserAddRows = "False" >

                <DataGrid.Columns >
                    <DataGridTextColumn Header = " Item" Width = "*"  Binding = "{Binding Item}"/>
                    <DataGridTextColumn Header = " Type" Width = "*"  Binding = "{Binding Type}"/>
                    <DataGridTextColumn Header = " Cost($)" Width = "*" Binding = "{Binding Price}"/>
                </DataGrid.Columns>

Удалить повторяющиеся столбцы и удалить последнюю пустую строку:

AutoGenerateColumns = "False" CanUserAddRows = "False"

Xaml:

<Window x:Class = "WpfApp5.MainWindow"
        xmlns = "http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x = "http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d = "http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc = "http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local = "clr-namespace:WpfApp5"
        mc:Ignorable = "d"
        Title = "MainWindow" Height = "450" Width = "800">
    <Grid>
        <TextBlock>Electronics:</TextBlock>

        <StackPanel Grid.Row = "0" Grid.Column = "1" Margin = "5">
            <DataGrid x:Name = "DataGridInvoices" ItemsSource = "{Binding}"  Height = "236" Width = "636" AutoGenerateColumns = "False" CanUserAddRows = "False" >

                <DataGrid.Columns >
                    <DataGridTextColumn Header = " Item" Width = "*"  Binding = "{Binding Item}"/>
                    <DataGridTextColumn Header = " Type" Width = "*"  Binding = "{Binding Type}"/>
                    <DataGridTextColumn Header = " Cost($)" Width = "*" Binding = "{Binding Price}"/>
                </DataGrid.Columns>

                <DataGrid.Resources>
                    <Style TargetType = "{x:Type DataGridColumnHeader}">
                        <Setter Property = "Background" Value = "#3280fc"/>
                        <Setter Property = "FontWeight" Value = "SemiBold"/>
                        <Setter Property = "BorderThickness" Value = "0,0,1,2"/>
                        <Setter Property = "BorderBrush" Value = "Black"/>

                    </Style>
                </DataGrid.Resources>
            </DataGrid>

        </StackPanel>

        <ComboBox x:Name = "ComboBox1" HorizontalAlignment = "Left" Margin = "298,300,0,0" VerticalAlignment = "Top" Width = "120" SelectionChanged = "ComboBox1_SelectionChanged">
            <ComboBoxItem Content = "Laptop"/>
            <ComboBoxItem Content = "PC"/>
            <ComboBoxItem Content = "Stove"/>
            <ComboBoxItem Content = "Camera"/>
        </ComboBox>
    </Grid>
</Window>

Код:

using System.Collections.Generic;
using System.Windows;
using System.Windows.Controls;

namespace WpfApp5
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        Invoice invoice;
        List<Invoice> Laptop = new List<Invoice>()
            {
                new Invoice(){Item  = "0",Type = "A",Price=10000},
                new Invoice(){Item  = "1",Type = "B",Price=20000},
                new Invoice(){Item  = "2",Type = "A",Price=15000},
            };
        public MainWindow()
        {
            InitializeComponent();
        }
        private class Invoice
        {
            public string Item { get; set; }
            public string Type { get; set; }
            public double Price { get; set; }
        }

        private void ComboBox1_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            //Intercept the selected name
            string sel = ComboBox1.SelectedItem.ToString();
            string Rsel = sel.Substring(sel.IndexOf(" ") + 1);
            if (Rsel == "Laptop")
            {
                DataGridInvoices.ItemsSource = Laptop;
            }
        }
    }

}