ArcGIS Engine基礎（2）之各類資料源管理（AGSServer）

實作根據字元串擷取AGSServer圖層

private static AGSServerDataSource _instance = null;
        // 擷取執行個體互斥鎖
        private static readonly object _getInstanceMutexLocker = new object();
        public static readonly char DATASOURCE_SPLIT_CHAR = '|';
        public static readonly char LAYER_PATH_SEPARATOR = '＼';

        private AGSServerDataSource() { }

        public static AGSServerDataSource CreateSingleton() {
            if (_instance != null)
                return _instance;

            lock (_getInstanceMutexLocker) {
                if (_instance == null)
                    _instance = new AGSServerDataSource();
            }

            return _instance;
        }

        public AGSServerLayerSetting GetAGSServerLayerSetting(string layerDataSourceString) {
            if (string.IsNullOrEmpty(layerDataSourceString)) return null;

            string[] dataSourceStrings = layerDataSourceString.Split(DATASOURCE_SPLIT_CHAR);

            string url = dataSourceStrings[0];
            string mapServerName = GetDataSourceValue(dataSourceStrings, "mapserver=");
            string layers = GetDataSourceValue(dataSourceStrings, "layers=");

            return new AGSServerLayerSetting(url, mapServerName, layers.Split(','));
        }


        public ILayer OpenLayer(string layerDataSourceString) {
            try {
                AGSServerLayerSetting agsLayerSetting = GetAGSServerLayerSetting(layerDataSourceString);

                IAGSServerConnection connection = GetServerConnection(agsLayerSetting.Url);
                IAGSEnumServerObjectName serverObjectNames = connection.ServerObjectNames;
                Dictionary<string, IAGSServerObjectName> mapServerObjects = GetMapServerObjects(serverObjectNames);

                if (mapServerObjects.ContainsKey(agsLayerSetting.MapServerName)) {
                    IAGSServerObjectName serverObjectName = mapServerObjects[agsLayerSetting.MapServerName];
                    IMapServerLayer layer = new MapServerLayerClass();
                    (layer as IDataLayer).Connect(serverObjectName as IName);
                    Dictionary<string, ILayer> layers = new Dictionary<string, ILayer>();
                    LayerWrapper.GetCompositeSubLayers(layer as ILayer, ref layers);
                    foreach (KeyValuePair<string, ILayer> kvp in layers) {
                        kvp.Value.Visible = agsLayerSetting.LayerNames.Contains(
                            kvp.Key.Substring(kvp.Key.IndexOf('\\') + 1).Replace('\\', LAYER_PATH_SEPARATOR));
                    }

                    return layer as ILayer;
                }
            }
            catch {
                throw;
            }

            return null;
        }

        public IEnvelope GetExtent(string layerDataSourceString) {
            ILayer layer = null;

            try {
                layer = OpenLayer(layerDataSourceString);
            }
            catch {
                throw;
            }

            IGeoDataset geoDataset = layer as IGeoDataset;
            if (geoDataset == null) return null;

            return geoDataset.Extent;
        }


        #region 公開方法

        public IAGSServerConnection GetServerConnection(string url) {
            try {
                return GetServerConnection(url, null, null);
            }
            catch (Exception) {
                throw;
            }
        }

        public IAGSServerConnection GetServerConnection(string url, string username, string password) {
            try {
                IAGSServerConnectionFactory connectionFactory = Activator.CreateInstance(Type.GetTypeFromProgID(
                    "esriGISClient.AGSServerConnectionFactory")) as IAGSServerConnectionFactory;

                IPropertySet propertySet = new PropertySet();
                propertySet.SetProperty("url", url);
                if (!string.IsNullOrEmpty(username) && !string.IsNullOrEmpty(password)) {
                    propertySet.SetProperty("user", username);
                    propertySet.SetProperty("password", password);
                }

                return connectionFactory.Open(propertySet, 0);
            }
            catch (Exception) {
                throw;
            }
        }

        public Dictionary<string, IAGSServerObjectName> GetMapServerObjects(IAGSEnumServerObjectName serverObjectNames) {
            Dictionary<string, IAGSServerObjectName> mapServerObjects = new Dictionary<string, IAGSServerObjectName>();

            IAGSServerObjectName serverObjectName = null;
            while ((serverObjectName = serverObjectNames.Next()) != null) {
                if (serverObjectName.Type.Equals("MapServer"))
                    mapServerObjects.Add(serverObjectName.Name, serverObjectName);
            }

            return mapServerObjects;
        }

        #endregion

        #region 私有方法

        private string GetDataSourceValue(string[] dataSourceStrings, string dataSourceKey) {
            foreach (string dataSourceString in dataSourceStrings) {
                if (dataSourceString.StartsWith(dataSourceKey, StringComparison.CurrentCultureIgnoreCase))
                    return dataSourceString.Substring(dataSourceKey.Length);
            }

            return string.Empty;
        }

        #endregion
           

/// <summary>
    /// ArcGIS Server圖層設定類
    /// </summary>
    public class AGSServerLayerSetting {

        #region ArcGIS Server位址屬性

        private string _url;
        public string Url {
            get {
                return _url;
            }
        }

        #endregion

        #region MapServer名稱

        private string _mapServerName;
        public string MapServerName {
            get {
                return _mapServerName;
            }
        }

        #endregion

        #region 圖層名數組屬性

        private string[] _layerNames;
        public string[] LayerNames {
            get {
                return _layerNames;
            }
        }

        #endregion

        #region 構造函數

        private AGSServerLayerSetting() { }

        public AGSServerLayerSetting(string url, string mapServerName, string[] layerNames) {
            _url = url;
            _mapServerName = mapServerName;
            _layerNames = layerNames;
        }

        #endregion

    }