How to use AutoCompleteExtender Ajax Control in C#.NET

AutoComplete is an ASP.NET AJAX extender that can be attached to any TextBox control, and will associate that control with a popup panel to display words that begin with the prefix typed into the textbox.

The dropdown with candidate words supplied by a web service is positioned on the bottom left of the text box.

Free Download

AutoCompleteExtender Ajax Control : Demo Project 

Free Download Ajax Toolkit

aspx Page Code:

<form id="form1" runat="server">
    <div style="border-style: groove; border-width: thin; color:

#800080; width: 700px; height: 500px; background-color: #CCCCFF;">

        <asp:ScriptManager ID="ScriptManager1" runat="server"> 

 </asp:ScriptManager>
        <br />
        <br />
        <br />
&nbsp;&nbsp;&nbsp;&nbsp;
        Google Seach:
        <asp:TextBox ID="TextBox1" runat="server" Font-Bold="True" Font-Names=

 "Verdana" Font-Size="10pt" ForeColor="#000066" Width="500px"></asp:TextBox>

        <cc1:AutoCompleteExtender ID="AutoCompleteExtender1" runat="server"

 MinimumPrefixLength="1" TargetControlID="TextBox1" ServiceMethod=

 "getList" ServicePath="google.asmx"> </cc1:AutoCompleteExtender>

        <asp:Button ID="btnSubmit" runat="server" onclick="btnSubmit_Click" 

 Text="Search" BorderColor="#CCCCFF" Font-Bold="True"

 ForeColor="#660033" />
    </div>
    </form>

Google.asmx page code:

<%@ WebService Language="C#" Class="google" %>
using System;
using System.Collections.Generic;
using System.Web;
using System.Collections;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Xml;

  /// <summary> /// Summary description for google /// </summary> [WebService(Namespace = "http://tempuri.org/")] [WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)] [System.Web.Script.Services.ScriptService] public class google : System.Web.Services.WebService { [WebMethod] public string[] getList(String prefixText)

 {
        XmlDocument doc = new XmlDocument();
        List<String> suggArList = new List<string>();
        string url = "http://google.com/complete/search?output=toolbar&q=" + prefixText;
        doc.Load(url);
        foreach (XmlNode node in doc.SelectNodes("//CompleteSuggestion"))
        {
            string value = node.SelectSingleNode("suggestion/@data").InnerText;
            suggArList.Add(value);
        }
        return suggArList.ToArray();
    }
}