Question

I have the following code behind a button in Visual Studio 2010

private void button1_Click(object sender, EventArgs e)
{
    SqlCeConnection Con = new SqlCeConnection();

    Con.ConnectionString = "Data Source = 'DB.sdf';" + "Password='my Password';";

    SqlCeCommand Query = new SqlCeCommand("SELECT Password FROM Admin");

    try        
    {
       Con.Open();
    }
    catch(Exception ex)
    {
       MessageBox.Show(ex.Message);
    }

    SqlCeDataReader Reader=Query.ExecuteReader();
    MessageBox.Show(Reader["Password"].ToString());
}

It works fine execute and no exception in connection but when I press the button it raises an exception saying

Error: Execute Reader Connection Property Has Not Been Initialized

Answer 1

You are not associating your command with your connection – try this:

SqlCeConnection Con = new SqlCeConnection("Data Source = 'AlviMBRental.sdf';Password='my Password';";

SqlCeCommand Query = new SqlCeCommand("SELECT Password FROM Admin", Con);  //   <== specify "Con" here!

Otherwise, your SqlCeCommand has no connection to work with….