Show login form after pressing F12 Key - asp.net

Question

I have an App in Winforms. VS 2010 C#.
What i am trying to do is when the user that is logged in. presses the F12 key the Login form shows up and another user enters the username and password and logs in.
I have attached my Login.cs, Program.cs and Form1.cs
In my main form(Form1.cs) when the user presses the F12 key i am able to show the login form but when i enter the username and password nothing happens.
Right now i am capturing the username when the user first time logs in. I also want to capture the new user when presses the F12 key and logs in.
i am showing the username in a label
label1.Text = myuser.getUserName();
I have tried some code in FORM.CS under Keypress event but it doesn't work
//////////**Program.CS**////////////////
namespace BusinessLayer
{
static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
DialogResult result;
var loginForm = new Login();
result = loginForm.ShowDialog();
if (result == DialogResult.OK)
{
// login was successful
Application.Run(new Form1(loginForm.usr));
}
}
}
}
///////////////////////////////////**Login.CS**/////////////////////
namespace BusinessLayer
{
public partial class Login : Form
{
UserName myuser;
public Login()
{
InitializeComponent();
}
private void btnLogin_Click(object sender, EventArgs e)
{
if (CheckPasswordManager.CheckPassword(txtUserID.Text, txtPassword.Text) > 0)
{
usr = new UserName(txtUserID.Text);
DialogResult = DialogResult.OK;
}
else
{
MessageBox.Show("wrong");
}
}
public UserName usr
{
get
{
return myuser;
}
set
{
myuser = value;
}
}
}
}
//////////////////////**Form1.CS**////////////////
namespace BusinessLayer
{
public partial class Form1 : Form
{
UserName myuser;
public Form1(UserName usr)
{
myuser = usr;
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
dataGridView1.DataSource = BookingManager.GetList();
label1.Text = myuser.getUserName();
int GetBookEntryID = Int32.Parse(this.dataGridView1.CurrentRow.Cells["booking_entry_id"].Value.ToString());
dataGridView2.DataSource = ProcessManager.GetList(GetBookEntryID);
}
private void Form1_KeyDown(object sender, KeyEventArgs e)
{
String s = e.KeyCode.ToString();
switch (s)
{
case "F12":
var loginForm = new Login();
this.Hide();
var loginForm = new Login();
loginForm.Show();
}
}
}
}
////////////////username.cs
namespace PassUsername
{
public class Username
{
string userName;
public Username(string uName)
{
userName = uName;
}
public string getUserName()
{
return userName;
}
}
}