Database :
CREATE TABLE [dbo].[STUDENT](
[StudentID] [int] IDENTITY(1,1) NOT NULL,
[Name] [nvarchar](50) NULL,
[RollNumber] [decimal](10, 2) NULL,
[Class] [nvarchar](50) NULL
) ON [PRIMARY]
GO
SET IDENTITY_INSERT [dbo].[STUDENT] ON
INSERT [dbo].[STUDENT] ([StudentID], [Name], [RollNumber], [Class]) VALUES (1, N'Andy', CAST(100.00 AS Decimal(10, 2)), N'MCA')
INSERT [dbo].[STUDENT] ([StudentID], [Name], [RollNumber], [Class]) VALUES (7, N'Anar', CAST(100.00 AS Decimal(10, 2)), N'MCA')
INSERT [dbo].[STUDENT] ([StudentID], [Name], [RollNumber], [Class]) VALUES (3, N'Bill', CAST(200.00 AS Decimal(10, 2)), N'BCA')
INSERT [dbo].[STUDENT] ([StudentID], [Name], [RollNumber], [Class]) VALUES (8, N'Amit', CAST(100.00 AS Decimal(10, 2)), N'MCA')
INSERT [dbo].[STUDENT] ([StudentID], [Name], [RollNumber], [Class]) VALUES (9, N'Anjali', CAST(200.00 AS Decimal(10, 2)), N'BCA')
INSERT [dbo].[STUDENT] ([StudentID], [Name], [RollNumber], [Class]) VALUES (6, N'Chris', CAST(300.00 AS Decimal(10, 2)), N'MBBS')
INSERT [dbo].[STUDENT] ([StudentID], [Name], [RollNumber], [Class]) VALUES (10, N'Avinash', CAST(200.00 AS Decimal(10, 2)), N'BCA')
INSERT [dbo].[STUDENT] ([StudentID], [Name], [RollNumber], [Class]) VALUES (11, N'Rohan', CAST(200.00 AS Decimal(10, 2)), N'BCA')
SET IDENTITY_INSERT [dbo].[STUDENT] OFF
Connection string in Web.config :
<connectionStrings>
<add name="Web" connectionString="Data Source=*;Initial Catalog=dbname;uid=sa;pwd=sql" providerName="System.Data.SqlClient"/>
</connectionStrings>
Asp.Net :
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %>
<!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>Auto Complete Extender Using Web Services</title>
<script type="text/javascript">
function ShowProcessImage() {
var autocomplete = document.getElementById('txtStudent');
autocomplete.style.backgroundImage = 'url(loading.gif)';
autocomplete.style.backgroundRepeat = 'no-repeat';
autocomplete.style.backgroundPosition = 'right';
}
function HideProcessImage() {
var autocomplete = document.getElementById('txtStudent');
autocomplete.style.backgroundImage = 'none';
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:ScriptManager ID="ScriptManager1" runat="server" EnablePageMethods="true">
</asp:ScriptManager>
<asp:TextBox ID="txtStudent" runat="server"></asp:TextBox>
<cc1:AutoCompleteExtender ServiceMethod="GetStudents" MinimumPrefixLength="1" ServicePath="WebService.asmx"
CompletionInterval="100" EnableCaching="false" CompletionSetCount="10" TargetControlID="txtStudent"
ID="AutoCompleteExtender1" runat="server" FirstRowSelected="false" OnClientPopulating="ShowProcessImage" OnClientPopulated="HideProcessImage">
</cc1:AutoCompleteExtender>
</div>
</form>
</body>
</html>
WebService.CS
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
/// <summary>
/// Summary description for WebService
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
// To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
[System.Web.Script.Services.ScriptService]
public class WebService : System.Web.Services.WebService
{
public WebService()
{
//Uncomment the following line if using designed components
//InitializeComponent();
}
[WebMethod]
public List<string> GetStudents(string prefixText, int count)
{
using (SqlConnection conn = new SqlConnection())
{
conn.ConnectionString = ConfigurationManager.ConnectionStrings["Web"].ConnectionString;
using (SqlCommand cmd = new SqlCommand())
{
cmd.CommandText = "select Name, StudentID from STUDENT where " + "Name like @prefix + '%' ";
cmd.Parameters.AddWithValue("@prefix", prefixText);
cmd.Connection = conn;
conn.Open();
List<string> students = new List<string>();
using (SqlDataReader sdr = cmd.ExecuteReader())
{
while (sdr.Read())
{
students.Add(sdr["Name"].ToString());
}
}
conn.Close();
return students;
}
}
}
}