C#

nstk wrote:

I think I'messed it up having installed some of the german and/or the english versions of Visual Studio.

Mark Salsbery
Microsoft MVP - Visual C++

try
{
//Your code goes here
}

catch(Exception exp){MessageBox.Show(exp.Message);}
finally
{
   // Close data reader object and database connection
 if (rdr != null)
 rdr.Close();

 if (con.State == ConnectionState.Open)
  con.Close();
}

using (SqlDataReader reader = cmd.ExecuteReader()) {
    while (reader.Read()) {
        if (txtUsername.Text == (reader["UserName"].ToString()) && txtPassword.Text = reader["Password"].ToString())) {
            // whatever needs to be done on a match
            break;  // optionally shortcircuit the remainder of the loop
        }
    }
} // close the using statement, this automatically calls Dispose()

try
{

	SqlConnection conn = new SqlConnection("");	 
	conn = DataHandler.conn;	 
	String username = txtUsername.Text;
	String password = txtPassword.Text;
	SqlCommand cmd = new SqlCommand("SELECT * FROM [TBLUsers]", conn);
	conn.Open();
	DataTable table = new DataTable();
	SqlDataReader reader = null;
	reader = cmd.ExecuteReader();
	while (reader.Read())
	{
		if (txtUsername.Text == (reader["UserName"].ToString()) && txtPassword.Text = reader["Password"].ToString()))
		{
			table.Load(reader);
			POS2 p = new POS2();
			MainPage page = (MainPage)this.MdiParent;
			p.MdiParent = page;
			p.WindowState = FormWindowState.Maximized;
			p.Show();
			page.WelcomeUser = reader["UserName"].ToString();
			 
			//throw new CustomException("Enter Correct Username and Password");

		}
	}
}
catch
{
	reader.Dispose();
}
finally
{
	conn.close();
}

Invalid attempt to call MetaData when reader is closed.