ช่วยด้วยครับส่งข้อมูล ข้าม FORM ไม่ได้ ทำจากโปรแกรม Sharpdevelop ครับ

namespace Project
{
	/// <summary>
	/// Description of MainForm.
	/// </summary>
	public partial class MainForm : Form
	{	
		MySqlConnection con1;
		MySqlCommand cmd1;
		MySqlDataReader reader;
		public string eid = "0";
		public MainForm()
		{
			//
			// The InitializeComponent() call is required for Windows Forms designer support.
			//
			InitializeComponent();
			
			//
			// TODO: Add constructor code after the InitializeComponent() call
			//
		}
private bool CompareStrings(string string1, string string2)  
      	{	  
            return String.Compare(string1, string2, true, System.Globalization.CultureInfo.InvariantCulture) == 0 ? true : false;  
       	}  
		
		void Button1Click(object sender, EventArgs e)
		{
			try
			{
				string url = "Server=localhost;Database=golf;uid=root;password=1234";
				string q = "SELECT emp_id,emp_username,emp_password FROM employee WHERE emp_username='" + textusername.Text + "' and emp_password='" + textpassword.Text + "'";
				con1 = new MySqlConnection(url);
				con1.Open();
				cmd1 = new MySqlCommand();
				cmd1.Connection = con1;
				cmd1.CommandText = q;
				reader = cmd1.ExecuteReader();
				
				string userText = textusername.Text;
				string passText = textpassword.Text;
				
				while (reader.Read())
				{
					if (this.CompareStrings(reader["emp_username"].ToString(), userText) &&
					    this.CompareStrings(reader["emp_password"].ToString(), passText)){
						eid = reader["emp_id"].ToString();
						MessageBox.Show("Login Successful");
					}
					else
					{
						MessageBox.Show("Error");
					}
					
				}
				con1.Close();
				
			}
			catch(Exception ex)
			{
				MessageBox.Show(ex.Message);
				textusername.Text = "";
				textpassword.Text = "";
			}
		}

void Button2Click(object sender, EventArgs e)
		{
			MainForm m1 = new MainForm();
			MessageBox.Show(m1.eid);
}