Introduction
This article demonstrates an interesting and very useful concept in LINQ-to-SQL.
Question: What is delete data with LINQ-to-SQL via WCF service?
In simple terms "It provides the ability to delete data from a DB using LINQ-to-SQL context using a WCF Service".
Step 1: Create a new web application
Step 2: Create a new WCF service application
Step 3: Adding a new LINQ-to-SQL
Step 4: The complete code of IService1.cs is as in the following:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.ServiceModel.Web;
using System.Text;
namespace WCFServiceApp
{
// NOTE: You can use the "Rename" command on the "Refactor" menu to change the interface name "IService1" in both code and config file together.
[ServiceContract]
public interface IService1
{
[OperationContract]
List<Employee> GetAllEmployees();
[OperationContract]
void DeleteEmpData(int a);
}
}
Step 5: The complete code of Service1.svc.cs is as in the following:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.ServiceModel.Web;
using System.Text;
namespace WCFServiceApp
{
// NOTE: You can use the "Rename" command on the "Refactor" menu to change the class name "Service1" in code, svc and config file together.
public class Service1 : IService1
{
public List<Employee> GetAllEmployees()
{
var query = from r in objContext.Employees select r;
return query.ToList();
}
public void DeleteEmpData(int a)
{
objContext.DeleteData(a);
}
#region Instance MembersDataClasses1DataContext objContext = new DataClasses1DataContext();
#endregion
}
}
Step 6: Adding a service reference
Step 7: The complete code of WebForm1.aspx is as in the following:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="DeleteData_WCF_LINQtoSQL.WebForm1" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<style type="text/css">
.grid
{
margin-top: 50px;
}
</style>
<title></title>
</head>
<body>
<form id="form1" runat="server">
<center>
<div>
<table>
<tr>
<td colspan="2" align="center">
<asp:Label ID="Label1" runat="server" Text="Delete Data using LINQ-to-SQL via WCF"
Font-Bold="true" Font-Size="Large" Font-Names="Verdana" ForeColor="Maroon"></asp:Label>
</td>
</tr>
<tr>
<td>
<asp:Label ID="Label2" runat="server" Text="Please Enter Employee Id" ForeColor="Brown"
Font-Bold="true" Font-Size="Medium" Font-Names="Verdana"></asp:Label>
</td>
<td>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:Button ID="Button1" runat="server" Text="Delete Data" Font-Names="Verdana" Width="213px"
BackColor="Orange" Font-Bold="True" OnClick="Button1_Click" />
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:GridView ID="GridView1" runat="server" CssClass="grid" BackColor="LightGoldenrodYellow"
BorderColor="Tan" BorderWidth="1px" CellPadding="2" AutoGenerateColumns="false"
ForeColor="Black" GridLines="None">
<AlternatingRowStyle BackColor="PaleGoldenrod" />
<FooterStyle BackColor="Tan" />
<HeaderStyle BackColor="Tan" Font-Bold="True" />
<PagerStyle BackColor="PaleGoldenrod" ForeColor="DarkSlateBlue" HorizontalAlign="Center" />
<SelectedRowStyle BackColor="DarkSlateBlue" ForeColor="GhostWhite" />
<SortedAscendingCellStyle BackColor="#FAFAE7" />
<SortedAscendingHeaderStyle BackColor="#DAC09E" />
<SortedDescendingCellStyle BackColor="#E1DB9C" />
<SortedDescendingHeaderStyle BackColor="#C2A47B" />
<Columns>
<asp:BoundField DataField="EmpId" HeaderText="Id" />
<asp:BoundField DataField="FirstName" HeaderText="FirstName" />
<asp:BoundField DataField="LastName" HeaderText="LastName" />
<asp:BoundField DataField="Age" HeaderText="Age" />
</Columns>
</asp:GridView>
</td>
</tr>
<tr>
<td colspan="2" align="center">
<asp:Label ID="Label3" runat="server" Font-Bold="true" Font-Size="Medium" Font-Names="Verdana"></asp:Label>
</td>
</tr>
</table>
</div>
</center>
</form>
</body>
</html>
Step 8: The complete code of WebForm1.aspx.cs is as in the following:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using DeleteData_WCF_LINQtoSQL.ServiceReference1;namespace DeleteData_WCF_LINQtoSQL
{
public partial class WebForm1 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
if (string.IsNullOrEmpty(TextBox1.Text))
{
Label3.Text = "Please Enter Some Values";
Label3.ForeColor = System.Drawing.Color.Red;
}
else
{
objClient.DeleteEmpData(int.Parse(TextBox1.Text));
GridView1.DataSource = objClient.GetAllEmployees();
GridView1.DataBind();
Label3.Text = "Records Deleted Successfully";
Label3.ForeColor = System.Drawing.Color.Green;
TextBox1.Text = string.Empty;
}
}
#region Instance MembersService1Client objClient = new Service1Client();
#endregion
}
}
Step 9: The output of the application is as in the following:
Step 10: The deleted data output of the application is as in the following:
I hope this article was useful for you.