Integrating Salesforce Web service with Asp.Net :

Salesforce web service:

global class LeadInfo
{
    WebService static List<Lead> GetLeadInfo() 
    {
        List<Lead> Leadinfo = new List<Lead>();
        Leadinfo=[SELECT FirstName,LastName,Email from Lead limit 5];
        return Leadinfo; 
    }
}

Design  a ASP.Net page as just like below:

 

C# Code:

using System;

using System.Data;

using System.Configuration;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using Enterprize;

using LeadInfo_Service;

public partial class Default2 : System.Web.UI.Page

{

    private string userid = "anyone@someone.com";// Salesforce user id

    private string password = "password"; // password

    private string sessionId;

    private string serverUrl;

    private string leadEmail;

    private DateTime nextLoginTime;

   

    protected void Page_Load(object sender, EventArgs e)

    {

        Panel1.Visible = false;

    }

    protected void Button1_Click(object sender, EventArgs e)

    {

        if (Application["_sessionId"] == null)

            Application["_sessionId"] = "";

        if (Application["_serverUrl"] == null)

            Application["_serverUrl"] = "";

        if (Application["_nextLoginTime"] == null)

            Application["_nextLoginTime"] = " #1/1/2000#";

        if (!isConnected())

            getSessionInfo();

        //       ' Call getLeadInfo Web Service

        Panel1.Visible = true;

        LeadInfoService getLeadInfo = new LeadInfoService();

        getLeadInfo.SessionHeaderValue = new LeadInfo_Service.SessionHeader();

        getLeadInfo.SessionHeaderValue.sessionId = sessionId;

        LeadInfo_Service.Lead[] getres = new LeadInfo_Service.Lead[1];

        getres = getLeadInfo.GetLeadInfo();

        int i;

        for (i = 0; i < getres.Length; i++)

        {

            FirstName.Items.Add((i+1)+")"+getres[i].FirstName);

            LastName.Items.Add((i + 1) + ")" + getres[i].LastName);

            Email.Items.Add((i + 1) + ")" + getres[i].Email);

        }

    }

    public Boolean isConnected()

    {

        if (sessionId != "" & sessionId != null)

        {

            if (DateTime.Now > nextLoginTime)

                return false;

            else

                return true;

        }

        else

            return false;

    }

    public void getSessionInfo()

    {

        Enterprize.LoginResult lr;

        Enterprize.SforceService ss = new Enterprize.SforceService();

        lr = ss.login(userid, password);

        sessionId = lr.sessionId;

        Application["sessionId"] = lr.sessionId;

        serverUrl = lr.serverUrl;

        Application["serverUrl"] = lr.serverUrl;

        Application["nextLoginTime"] = DateTime.Now;

    }

}