this.panelProps.Enabled = false;
                buttonSync.Text = "Synchronize";
            }
        }

        // This function loads the connection information info from the "ApplicationProperties" table.
        //
        private void LoadAppProps() {
            // Create a SqlCeCommand object associated with the connection to NorthwindDemo database.
            //
            SqlCeCommand cmd = dataNorthwind.NorthwindConnection.CreateCommand();

            // Load the connect information from the ApplicationProperties table in the NorthwindDemo database.
            //
            cmd.CommandText = @"SELECT InternetURL, InternetLogin, InternetPassword, Publisher, PublisherLogin, PublisherPassword, PublisherSecurityMode, Subscriber FROM ApplicationProperties;";

            SqlCeDataReader drAppProp = null;

            try {

                drAppProp = cmd.ExecuteReader();
                if (drAppProp.Read()) {
                    int index;

                    // Get the Internet URL data.
                    //
                    index = drAppProp.GetOrdinal("InternetURL");
                    if (!drAppProp.IsDBNull(index)) {
                        this.textBoxInternetUrl.Text = drAppProp.GetString(index);
                    }
                    else {
                        this.textBoxInternetUrl.Text = "";
                    }

                    // Get the Internet login data.
                    //
                    index = drAppProp.GetOrdinal("InternetLogin");
                    if (!drAppProp.IsDBNull(index)) {
                        this.textBoxInternetLogin.Text = drAppProp.GetString(index);
                    }
                    else {
                        this.textBoxInternetLogin.Text = "";
                    }

                    // Get the Internet password data.
                    //
                    index = drAppProp.GetOrdinal("InternetPassword");
                    if (!drAppProp.IsDBNull(index)) {
                        this.textBoxInternetPwd.Text = drAppProp.GetString(index);
                    }
                    else {
                        this.textBoxInternetPwd.Text = "";
                    }

                    // Get the publisher data.
                    //
                    index = drAppProp.GetOrdinal("Publisher");
                    if (!drAppProp.IsDBNull(index)) {
                        this.textBoxPublisher.Text = drAppProp.GetString(index);
                    }
                    else {
                        this.textBoxPublisher.Text = "";
                    }

                    // Get the publisher login data.
                    //
                    index = drAppProp.GetOrdinal("PublisherLogin");
                    if (!drAppProp.IsDBNull(index)) {
                        this.textBoxUserID.Text = drAppProp.GetString(index);
                    }
                    else {
                        this.textBoxUserID.Text = "";
                    }

                    // Get the publisher password data.
                    //
                    index = drAppProp.GetOrdinal("PublisherPassword");
                    if (!drAppProp.IsDBNull(index)) {
                        this.textBoxPassword.Text = drAppProp.GetString(index);
                    }
                    else {
                        this.textBoxPassword.Text = "";
                    }

                    // Get the publisher security mode data.
                    //
                    index = drAppProp.GetOrdinal("PublisherSecurityMode");
                    if (!drAppProp.IsDBNull(index)) {
                        this.radioButtonSQLAuth.Checked = (1 == drAppProp.GetByte(index));
                    }
                    else {
                        this.radioButtonSQLAuth.Checked = true;
                    }

                    // Get the subscriber data.
                    //
                    index = drAppProp.GetOrdinal("Subscriber");
                    if (!drAppProp.IsDBNull(index)) {
                        this.textBoxSubscriber.Text = drAppProp.GetString(index);
                    }
                    else {
                        this.textBoxSubscriber.Text = "";
                    }
                }
            }
            finally {
                drAppProp.Close();
            }
        }

        // This function saves the connecting information in the "ApplicationProperties" table.
        //
        private void SaveAppProps() 
        {
            // Create the "ApplicationProperties" table.
            //
            SqlCeCommand cmd = dataNorthwind.NorthwindConnection.CreateCommand();
            cmd.CommandText = @"CREATE TABLE ApplicationProperties (" + 
                "InternetURL NTEXT, " +
                "InternetLogin NVARCHAR(255), " +
                "InternetPassword NVARCHAR(255), " +
                "Publisher NVARCHAR(255), " +
                "PublisherLogin NVARCHAR(255), " +
                "PublisherPassword NVARCHAR(255), " +
                "PublisherSecurityMode TINYINT, " +
                "Subscriber NVARCHAR(255));";

            cmd.ExecuteNonQuery();

            // Save the connection information
            //
            cmd.CommandText = @"INSERT INTO ApplicationProperties " + 
                "(InternetURL, InternetLogin, InternetPassword, Publisher, PublisherLogin, PublisherPassword, PublisherSecurityMode, Subscriber) " +
                "VALUES (?, ?, ?, ?, ?, ?, ?, ?);";
            cmd.Parameters.Add("@p1", this.textBoxInternetUrl.Text);
            cmd.Parameters.Add("@p2", this.textBoxInternetLogin.Text);
            cmd.Parameters.Add("@p3", this.textBoxInternetPwd.Text);
            cmd.Parameters.Add("@p4", this.textBoxPublisher.Text);
            cmd.Parameters.Add("@p5", this.textBoxUserID.Text);
            cmd.Parameters.Add("@p6", this.textBoxPassword.Text);
            cmd.Parameters.Add("@p7", this.radioButtonSQLAuth.Checked ? 1 : 0);
            cmd.Parameters.Add("@p8", this.textBoxSubscriber.Text);

            cmd.ExecuteNonQuery();
        }

        // This function synchronizes the device database with the server database.
        //
        private void ReplSync() {
            SqlCeReplication replNorthwind = new SqlCeReplication();
			
            // Set the Internet properties.
            //
            replNorthwind.InternetUrl = textBoxInternetUrl.Text;
            replNorthwind.InternetLogin = textBoxInternetLogin.Text;
            replNorthwind.InternetPassword = textBoxInternetPwd.Text;

            // Set the Publisher properties.
            //
            replNorthwind.Publisher = textBoxPublisher.Text;
            replNorthwind.PublisherDatabase = publisherDatabase;
            replNorthwind.Publication = publication;
            replNorthwind.PublisherSecurityMode = radioButtonSQLAuth.Checked ? SecurityType.DBAuthentication : SecurityType.NTAuthentication;
            replNorthwind.PublisherLogin = textBoxUserID.Text;
            replNorthwind.PublisherPassword = textBoxPassword.Text;
			
            // Set the Subscriber properties.
            //
            replNorthwind.SubscriberConnectionString = dataNorthwind.LocalConnString;
            replNorthwind.Subscriber = textBoxSubscriber.Text;

            bool changed = false;

            // Starts the cursor icon since this function may take some time.
            //
            System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.WaitCursor;

            try 
            {
                if (ConnectionState.Open == dataNorthwind.NorthwindConnection.State) {
                    dataNorthwind.NorthwindConnection.Close();
                }

                if (init) {
                    
                    // Delete the database if the database exists.
                    // 
                    if (File.Exists(dataNorthwind.LocalDatabaseFile)) {
                        File.Delete(dataNorthwind.LocalDatabaseFile);
                    }

                    // Clear the dataset if it exists.
                    //
                    if (null != dataNorthwind.NorthwindDataSet) {
                        dataNorthwind.NorthwindDataSet.Clear();
                    }

                    // Create the Local SSCE Database subscription.
                    //
                    replNorthwind.AddSubscription(AddOption.CreateDatabase);
                }

                // Synchronize to the server database to populate the Subscription.
                //
                replNorthwind.Synchronize();

                System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Default;
                
                // Display the synchronization results.
                //
                MessageBox.Show("Synchronization Complete:\n" +
                    "Publisher changes = " + replNorthwind.PublisherChanges.ToString() + "\n" +
                    "Publisher conflicts = " + replNorthwind.PublisherConflicts.ToString() + "\n" +
                    "Subscriber changes = " + replNorthwind.SubscriberChanges.ToString(),
                    "Synchronize",
                    MessageBoxButtons.OK,
                    MessageBoxIcon.Asterisk,
                    MessageBoxDefaultButton.Button1);

                changed = replNorthwind.PublisherChanges > 0 || replNorthwind.PublisherConflicts > 0;
            }
            catch(SqlCeException e) {
                // Error handling mechanism
                //
                System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Default;
                NorthwindData.ShowErrors(e);
                if (init) 
                {
                    this.formNorthwind.UpdateMenu();
                    return;
                }
            }
            catch(Exception e) {
                // Error handling mechanism
                //
                System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Default;
                MessageBox.Show(e.Message, "Northwind");

                if (init) {
                    this.formNorthwind.UpdateMenu();
                    return;
                }
            }
            finally {
                // Dispose of the Replication Object
                //
                replNorthwind.Dispose();
            }

            try {
                // Open the connection to the Northwind database.
                //
                dataNorthwind.NorthwindConnection.Open();

                if (init) {
                    // Save the connection information
                    //
                    SaveAppProps();

                    // Set the initialization flag to false and disable the connection information controls.
                    //
                    init = false;
                    this.buttonSync.Text = "Synchronize";
                    this.panelProps.Enabled = false;
                }

                if (changed) {
                    formNorthwind.Refresh();
                }
            }
            catch(SqlCeException e) {
                NorthwindData.ShowErrors(e);
            }
            catch(Exception e) {
                MessageBox.Show(@"Save connection information: " + e.Message, "Northwind");
            }
        }

        private void radioButtonSQLAuth_CheckedChanged(object sender, System.EventArgs e) {
            if (this.radioButtonSQLAuth.Checked) {
                this.textBoxUserID.Enabled = true;
                this.textBoxPassword.Enabled = true;
            }
            else {
                this.textBoxUserID.Enabled = false;
                this.textBoxPassword.Enabled = false;
            }
        }

        private void buttonReset_Click(object sender, System.EventArgs e) {
            if (DialogResult.OK == MessageBox.Show("You are about to reset all data. Continuing will discard all changes.", 
                "Northwind", 
                MessageBoxButtons.OKCancel, 
                MessageBoxIcon.Asterisk, 
                MessageBoxDefaultButton.Button1)) {
                if (ConnectionState.Open == dataNorthwind.NorthwindConnection.State) {
                    dataNorthwind.NorthwindConnection.Close();
                }

                try {
                    if (File.Exists(dataNorthwind.LocalDatabaseFile)) {
                        File.Delete(dataNorthwind.LocalDatabaseFile);
                    }

                    // Clear the dataset if it exists.
                    //
                    if (null != dataNorthwind.NorthwindDataSet) {
                        dataNorthwind.NorthwindDataSet.Clear();
                    }
                }
                catch(Exception err) {
                    MessageBox.Show(err.Message, "Northwind");
                    return;
                }

                init = true;
                this.panelProps.Enabled = true;
                buttonSync.Text = "Initialize";
				formNorthwind.UpdateMenu();
            }
        }

        private void buttonSync_Click(object sender, System.EventArgs e) {
            if (DialogResult.OK == MessageBox.Show("You are about to synchronize your data. Continue?", 
                "Northwind", 
                MessageBoxButtons.OKCancel, 
                MessageBoxIcon.Asterisk, 
                MessageBoxDefaultButton.Button1)) {
                ReplSync();
                formNorthwind.UpdateMenu();
            }
        }	
    }
}