C#

I need to access my gmail contacts to upgrade an Access database. A program in C # manages this basis. I checked on the Internet and appeared several ways, but none worked. I found a video that the speaker creates the code step by step and in the end he managed to access the gmail contacts.
I typed the code and is giving an error in word in of code:
foreach (Contact contato in f.Entries)

The following code:

using System;
using System.Data;
using Google.Contacts;
using Google.GData.Client;
using Google.GData.Extensions;

namespace ContatosGmail
{
    public partial class Default : System.Web.UI.Page
    {

        protected void btnObter_Click(object sender, EventArgs e)
        {
            DataSet ds = new DataSet();
            ds.Tables.Add("GmailContacts");
            ds.Tables[0].Columns.Add("EmailId");
            RequestSettings rs = new RequestSettings("Taveira", txtUsername.Text, txtPassword.Text);
            rs.AutoPaging = true;
            ContactsRequest cr = new ContactsRequest(rs);
            Feed<Contact> f = cr.GetContacts();
            
            foreach (Contact contato in f.Entries)
            {
                foreach (EMail email in contato.Emails)
                {
                    DataRow row = ds.Tables[0].NewRow();
                    row["EmailId"] = email.Address.ToString();
                    ds.Tables[0].Rows.Add(row);
                }
            }
            GridView1.DataSource = ds.Tables[0];
            GridView1.DataBind();
            lblStatus.Text = "Toal de contatos para " + txtUsername.Text + ": " + ds.Tables[0].Rows.Count.ToString();
        }
    }
}

I am in urgent need of this solution.
Using Visual Studio Professional 15 and Windows 10.
Thank you.