Question

How to remove items local database after added

 add("01:23:45:67:89:ac", "yes"); //add new item


    static void add(string id, string input)
    {
        using (SqlCeConnection connection = new SqlCeConnection("datasource=base.sdf"))
        {
            connection.Open();
            try
            {
                using (SqlCeCommand command = new SqlCeCommand("INSERT INTO userinput VALUES(@macadres, @userinput)", connection))
                {
                    command.Parameters.Add(new SqlCeParameter("macadres", id));
                    command.Parameters.Add(new SqlCeParameter("userinput", input));
                    command.ExecuteNonQuery();
                }
            }
            catch
            {
                Console.WriteLine("Not OK.");
            }
            connection.Close();
        }
    }

Need to remove added 01:23:45:67:89:ac

DeleteRecord(“01:23:45:67:89:ac”);

    static void DeleteRecord(string id)
    {
        using (SqlCeConnection connection = new SqlCeConnection("datasource=base.sdf"))
        {
            connection.Open();
            try
            {
                using (SqlCeCommand command = new SqlCeCommand("DELETE FROM userinput WHERE macadres ='" + id + "'"))
                {
                    command.Connection.Open();
                    command.ExecuteNonQuery();
                }
            }
            catch(Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            connection.Close();
        }
    }

Answer 1

 DeleteRecord("01:23:45:67:89:ac");

    static void DeleteRecord(string id)
    {
        using (SqlCeConnection connection = new SqlCeConnection("datasource=base.sdf"))
        {
            connection.Open();
            try
            {
                using (SqlCeCommand command = new SqlCeCommand("DELTE FROM userinput WHERE macadres ='"+ id +"'", connection);
                {
                    command.ExecuteNonQuery();
                }
            }
            catch
            {
                Console.WriteLine("Not OK.");
            }
            finally
            {
              connection.Close();
            }

        }
    }

Or you can create one method for delete any record by giving connection and query as bellow

string connectionstring = "datasource=base.sdf"; // "Data Source = MyDatabase.sdf; Password ='<pwd>'"
string deleteQuery = "DELTE FROM userinput WHERE macadres ='"+ id +"'";     

you can call as bellow

MyExecuteNonQuery( deleteQuery , connectionstring);

here ie the method implimentation

   private void MyExecuteNonQuery(string queryString,
        string connectionString)
    {
        SqlCeConnection conn = null;
        try
        {
            conn = new SqlCeConnection(connectionString);
            conn.Open();

            SqlCeCommand cmd = conn.CreateCommand();
            cmd.CommandText = queryString;

            cmd.ExecuteNonQuery();
        }
        finally
        {
            conn.Close();
        }
    }