Delete Data Using LINQ to SQL Class in WPF

Introduction

This article shows you how to delete data using LINQ to SQL in WPF applications.

Create a WPF application as Figure 1.

Figure 1: Create WPF application

Add LINQ to SQL classes to the project as in Figures 2 and 3.

 

Figure 2: Add LINQ to SQL

 

Figure 3: Choose database objects

MainWindow.xaml

<Window x:Class="DeleteData_WPF_LINQtoSQL.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525" Loaded="Window_Loaded">
    <Grid>
        <DataGrid x:Name="dgEmployee"
                  Width="267"
                  Margin="118,47,0,0"
                  HorizontalAlignment="Left"
                  VerticalAlignment="Top"
                  AutoGenerateColumns="False"
                  CanUserDeleteRows="True"
                  CanUserAddRows="False"
                  ColumnWidth="*">
            <DataGrid.Columns>
                <DataGridTextColumn x:Name="dgrEmpId"
                                    Binding="{Binding EmpId}"
                                    Header="EmpId"
                                    IsReadOnly="True" />
                <DataGridTextColumn x:Name="dgrFirstName"
                                    Binding="{Binding FirstName}"
                                    Header="FirstName"
                                    IsReadOnly="True" />
                <DataGridTextColumn x:Name="dgrLastName"
                                    Binding="{Binding LastName}"
                                    Header="LastName"
                                    IsReadOnly="True" />
                <DataGridTemplateColumn>
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <Button Content="Delete" x:Name="btnDelete" Click="btnDelete_Click"
                              ></Button>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
            </DataGrid.Columns>
        </DataGrid>
    </Grid>
</Window>

MainWindow.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Forms;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace DeleteData_WPF_LINQtoSQL
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
        }

        private void Window_Loaded(object sender, RoutedEventArgs e)
        {
            dgEmployee.ItemsSource = objContext.Employees.ToList();
        }

        DataClasses1DataContext objContext = new DataClasses1DataContext();

        private void btnDelete_Click(object sender, RoutedEventArgs e)
        {
            int empId = (dgEmployee.SelectedItem as Employee).EmpId;
            Employee employee = (from r in objContext.Employees where r.EmpId == empId select r).SingleOrDefault();
            objContext.Employees.DeleteOnSubmit(employee);
            objContext.SubmitChanges();
            dgEmployee.ItemsSource = objContext.Employees.ToList();
        }
    }
}

The output of the application is as in Figures 4 and 5.

 

Figure 4: Output of the application before applying delete operation

 

Figure 5: Output of the application after applying delete operation.

Summary

In this article we saw how to delete data using LINQ to SQL in WPF application.