Creating and Consuming a WCF Service

WCF Service

How to check if a User ID already exits or not in the database using a WCF Service.

In this article, I am going to discuss how to create a WCF Service and use in asp.net 3.5. You can also use this service at registration time to check duplicate data.

How to Create a WCF service

Step 1: To create new WCF Service Open new web site and select WCF service like as follows:

Step 2: By default you will get the following page.

Step 3: Now add the following code into Service class to get record from the database.

//This function is used to get Userid from database.
public DataSet GetUserId()
{
SqlConnection con = new SqlConnection("Data Source = Puru-SQLSERVER2005; Initial Catalog = Puru; User ID = sa; Password = wintellect;");
string cmd = "select UserID from Registration";
SqlDataAdapter da = new SqlDataAdapter(cmd, con);
con.Open();
DataSet ds = new DataSet();
da.Fill(ds);
con.Close();
return ds;
}

For example, Service.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;
using System.Data;
using System.Data.SqlClient;
public class Service: IService {
public string GetData(int value)
{
return string.Format("You entered: {0}", value);
}
public CompositeType GetDataUsingDataContract(CompositeType composite)
{
if (composite.BoolValue)
{
composite.StringValue += "Suffix";
}
return composite;
}
//This function is used to get Userid from database.
public DataSet GetUserId()
{
SqlConnection con = new SqlConnection("Data Source = Puru-SQLSERVER2005; Initial Catalog = Puru; User ID = sa; Password = wintellect;");
string cmd = "select UserID from Registration";
SqlDataAdapter da = new SqlDataAdapter(cmd, con);
con.Open();
DataSet ds = new DataSet();
da.Fill(ds);
con.Close();
return ds;
}
}

Service.svc

<%@ ServiceHost Language="C#" Debug="true" Service="Service" CodeBehind="~/App_Code/Service.cs" %>

Step 4

Build the application and debug; you will get the following output.

How to use WCF service in my application?

Step 5

If you want to use this service into different application then copy the URL of this wcf service like as http://localhost:1907/CheckValidUser_WCFService/Service.svc and add the reference of this service into an appropriate application like as

Paste the URL and click ok button

Step 6

And if you want to use wpf service in to same application then leave step 5. And add a new web page into first application.

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="CheckValidUser.aspx.cs" Inherits="CheckValidUser" %>
<!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 runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="textUserId" runat="server"></asp:TextBox>
<asp:Button ID="getUserId" runat="server" OnClick="getUserId_Click" Text="Verify" />
<asp:Label ID="lblMessage" runat="server"></asp:Label>
</div>
</form>
</body>
</html>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;
public partial class CheckValidUser : System.Web.UI.Page
{
Service wcfService = new Service();
protected void Page_Load(object sender, EventArgs e)
{
}
protected void getUserId_Click(object sender, EventArgs e)
{
DataSet ds = new DataSet();
ds = (wcfService.GetUserId());
if (ds.Tables[0].Rows.Count > 0)
{
foreach (DataRow row in ds.Tables[0].Rows)
{
string UserId = row["UserId"].ToString();
if (UserId == textUserId.Text)
{
lblMessage.Text = "Valid";
break;
}
else
lblMessage.Text = "InValid";
}
}
}
}

Output: You will get the following output.

Here I am entering a valid name which exists into database.

Here I am entering an invalid name which does not exist into database.

6 Comments

Join the conversation! Your thoughts help the community grow.

olivermode9y ago
Thank you! a great tutorial
Niresh kumar13y ago
very nice example to learn basic of WCF....thank u...
Kapil Garg14y ago
Nice examle..Keep it up Man
vinod singh15y ago
Nice example to learn the basic wcf
love sharma15y ago
Very Good Example to understand the basic of WCF.
- Purushottam Rathore15y ago
  Thanks Love.