Delete Data With LINQ-to-SQL Via WCF Service

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">

.grid

{

margin-top: 50px;

}

</style>

</head>

<body>

<div>

<table>

<tr>

<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>

<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>

<asp:GridView ID="GridView1" runat="server" CssClass="grid" BackColor="LightGoldenrodYellow"

BorderColor="Tan" BorderWidth="1px" CellPadding="2" AutoGenerateColumns="false"

ForeColor="Black" GridLines="None">

<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>

<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.