private void btnSubmit_Click(object sender, EventArgs e) { EmailClient client = null; var builder = new StringBuilder(); if (rdbImap.Checked) { client = new ImapClient(tbHostName.Text.Trim(), Convert.ToInt32(tbPortNo.Text.Trim()), cbIsSecure.Checked); } else { client = new Pop3Client(tbHostName.Text.Trim(), Convert.ToInt32(tbPortNo.Text.Trim()), cbIsSecure.Checked); } builder.AppendLine("% " + tbCommand.Text); client.Login(tbUserName.Text.Trim(), tbPassword.Text.Trim()); client.SelectMailbox(); builder.Append(client.ExecuteCommand(tbCommand.Text.Trim())); client.LogOut(); tbOutput.Text = builder.ToString(); builder.Remove(0, builder.Length); builder = null; }