UA-.NETStandard/SampleApplications/Samples/GDSClient/Controls/ViewServersOnNetworkDialog.cs

using System;
using System.Collections.Generic;
using System.Data;
using System.Text;
using System.Windows.Forms;
using Opc.Ua.Client.Controls;

namespace Opc.Ua.Gds
{
    public partial class ViewServersOnNetworkDialog : Form
    {
        public ViewServersOnNetworkDialog(GlobalDiscoveryServer gds)
        {
            InitializeComponent();
            Icon = ClientUtils.GetAppIcon();
            ServersDataGridView.AutoGenerateColumns = false;

            m_gds = gds;

            m_dataset = new DataSet();
            m_dataset.Tables.Add("Servers");

            m_dataset.Tables[0].Columns.Add("RecordId", typeof(uint));
            m_dataset.Tables[0].Columns.Add("ServerName", typeof(string));
            m_dataset.Tables[0].Columns.Add("DiscoveryUrl", typeof(string));
            m_dataset.Tables[0].Columns.Add("ServerCapabilities", typeof(string));
            m_dataset.Tables[0].Columns.Add("ServerOnNetwork", typeof(ServerOnNetwork));

            ServersDataGridView.DataSource = m_dataset.Tables[0];
        }

        private DataTable ServersTable { get { return m_dataset.Tables[0]; } }
        private DataSet m_dataset;
        private GlobalDiscoveryServer m_gds;

        public List<ServerOnNetwork> ShowDialog(IWin32Window owner, ref QueryServersFilter filters)
        {
            ServersTable.Rows.Clear();

            if (filters == null)
            {
                filters = new QueryServersFilter();
            }

            ApplicationUriTextBox.Text = filters.ApplicationUri;
            ApplicationNameTextBox.Text = filters.ApplicationName;
            ProductUriTextBox.Text = filters.ProductUri;
            
            if (base.ShowDialog(owner) != DialogResult.OK)
            {
                return null;
            }

            List<ServerOnNetwork> servers = new List<ServerOnNetwork>();

            foreach (DataRow row in ServersTable.Rows)
            {
                servers.Add((ServerOnNetwork)row[4]);
            }

            return servers;
        }

        private void ApplicationRecordDataGridView_SelectionChanged(object sender, EventArgs e)
        {
            try
            {
                SearchButton.Enabled = ServersDataGridView.SelectedRows.Count > 0;
            }
            catch (Exception exception)
            {
                MessageBox.Show(Text + ": " + exception.Message);
            }
        }

        private void SearchButton_Click(object sender, EventArgs e)
        {
            try
            {
                ServersTable.Rows.Clear();

                if (!m_gds.IsConnected)
                {
                    m_gds.SelectDefaultGds(null);
                }

                uint maxNoOfRecords = (uint)NumberOfRecordsUpDown.Value;

                var servers = m_gds.QueryServers(
                    maxNoOfRecords,
                    ApplicationNameTextBox.Text.Trim(),
                    ApplicationUriTextBox.Text.Trim(),
                    ProductUriTextBox.Text.Trim(),
                    ServerCapabilitiesTextBox.Tag as IList<string>);

                bool found = false;

                foreach (var server in servers)
                {
                    found = true;

                    if (maxNoOfRecords == 0)
                    {
                        SearchButton.Visible = false;
                        NextButton.Visible = true;
                        StopButton.Visible = true;
                        StopButton.Tag = servers;
                        break;
                    }

                    maxNoOfRecords--;

                    DataRow row = ServersTable.NewRow();

                    row[0] = server.RecordId;
                    row[1] = server.ServerName;
                    row[2] = server.DiscoveryUrl;

                    StringBuilder buffer = new StringBuilder();

                    if (server.ServerCapabilities != null)
                    {
                        foreach (var id in server.ServerCapabilities)
                        {
                            if (buffer.Length > 0)
                            {
                                buffer.Append(',');
                            }

                            buffer.Append(id);
                        }
                    }

                    row[3] = buffer.ToString();
                    row[4] = server;

                    ServersTable.Rows.Add(row);
                }

                if (!found)
                {
                    SearchButton.Visible = true;
                    SearchButton.Enabled = true;
                    NextButton.Visible = false;
                    StopButton.Visible = false;
                }

                ServersTable.AcceptChanges();

                if (ServersTable.Rows.Count == 0)
                {
                    MessageBox.Show(ParentForm, "No servers available that meet the filter criteria.", Text, MessageBoxButtons.OK, MessageBoxIcon.Information);                        
                }
            }
            catch (Exception exception)
            {
                MessageBox.Show(Text + ": " + exception.Message);
            }
        }

        private void NextButton_Click(object sender, EventArgs e)
        {
            try
            {
                IEnumerable<ServerOnNetwork> servers = (IEnumerable<ServerOnNetwork>)StopButton.Tag;
                StopButton.Visible = false;
                StopButton.Tag = null;

                uint maxNoOfRecords = (uint)NumberOfRecordsUpDown.Value;

                bool found = false;

                foreach (var server in servers)
                {
                    found = true;

                    if (maxNoOfRecords == 0)
                    {
                        SearchButton.Visible = false;
                        NextButton.Visible = true;
                        StopButton.Visible = true;
                        StopButton.Tag = servers;
                        break;
                    }

                    maxNoOfRecords--;

                    DataRow row = ServersTable.NewRow();

                    row[0] = server.RecordId;
                    row[1] = server.ServerName;
                    row[2] = server.DiscoveryUrl;

                    StringBuilder buffer = new StringBuilder();

                    if (server.ServerCapabilities != null)
                    {
                        foreach (var id in server.ServerCapabilities)
                        {
                            if (buffer.Length > 0)
                            {
                                buffer.Append(',');
                            }

                            buffer.Append(id);
                        }
                    }

                    row[3] = buffer.ToString();
                    row[4] = server;

                    ServersTable.Rows.Add(row);
                }

                if (!found)
                {
                    SearchButton.Visible = true;
                    SearchButton.Enabled = true;
                    NextButton.Visible = false;
                    StopButton.Visible = false;
                }

                ServersTable.AcceptChanges();
            }
            catch (Exception exception)
            {
                MessageBox.Show(Text + ": " + exception.Message);
            }
        }

        private void StopButton_Click(object sender, EventArgs e)
        {
            try
            {
                SearchButton.Visible = true;
                SearchButton.Enabled = true;
                StopButton.Visible = false;
                StopButton.Tag = null;
                NextButton.Visible = false;
            }
            catch (Exception exception)
            {
                MessageBox.Show(Text + ": " + exception.Message);
            }
        }

        private void ServerCapabilitiesButton_Click(object sender, EventArgs e)
        {
            try
            {
                var capabilities = new ServerCapabilitiesDialog().ShowDialog(this, ServerCapabilitiesTextBox.Tag as IList<string>);

                if (capabilities == null)
                {
                    return;
                }

                StringBuilder buffer = new StringBuilder();

                foreach (var capability in capabilities)
                {
                    if (buffer.Length > 0)
                    {
                        buffer.Append(",");
                    }

                    buffer.Append(capability);
                }

                ServerCapabilitiesTextBox.Text = buffer.ToString();
                ServerCapabilitiesTextBox.Tag = capabilities;
            }
            catch (Exception exception)
            {
                MessageBox.Show(Text + ": " + exception.Message);
            }
        }
    }

    public class QueryServersFilter
    {
        public string ApplicationUri;
        public string ApplicationName;
        public string ProductUri;
        public string[] ServerCapabilities;
    }
}