Hi
Here I m going to populate country list on page load using web service.
Step1: Create the Location Class like this
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;///
/// Summary description for Location
///namespace Test
{
[Serializable]
public class Location
{
public int CountryID
{ get; set; }public string CountryName
{ get; set; }}
}
Step2: write the webmethod in web service like this.
Note: donot forget to uncomment on this line “[System.Web.Script.Services.ScriptService]” for calling the web service from client side.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;
using Test;
using System.Data.SqlClient;
using System.Data;
using System.Web.Script.Services;///
/// Summary description for WebService
///[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 {[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json, UseHttpGet = true)]
public List FindAllCountries()
{
List locations = new List();
string connectionString =
“Data Source=.;Initial Catalog=Test;Integrated Security=True”;
using (SqlConnection connection = new SqlConnection(connectionString))
{
using (SqlCommand command = new SqlCommand())
{
command.Connection = connection;
command.CommandText = “SelectAllCountries”;
command.CommandType = CommandType.StoredProcedure;
connection.Open();
using (SqlDataReader dataReader = command.ExecuteReader())
{
Location location;
if (dataReader != null)
while (dataReader.Read())
{
location = new Location();
location.CountryID = (int)dataReader[“CountryID”];
location.CountryName = Convert.ToString(dataReader[“CountryName”]);
locations.Add(location);
}
}
}
}
return locations;
}}
Step3: Compile the web service and test it.
Step4: Create a default page and call the web service using script manager like this
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default_Ajax.aspx.cs" Inherits="WebService_Test_Default_Ajax" %>
<!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:ScriptManager ID="ScriptManager1" runat="server">
<Services>
<asp:ServiceReference Path="~/WebService.asmx" />
</Services>
</asp:ScriptManager><asp:DropDownList ID="ddl1" runat="server" Height="17px" Width="108px">
</asp:DropDownList>
</div>
<script type="text/javascript">
Sys.Application.add_load(function() {WebService.FindAllCountries(onSucess, null, null)
function onSucess(result)
{
var ddl = document.getElementById(‘<%=ddl1.ClientID %>’);
for (var i = 0; i < result.length; i++) {
ddl.options[i] = new Option(result[i].CountryName, result[i].CountryID);}
}});
</script></form>
</body>
</html>
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