创建内存工作空间

        /// <summary>
        /// 创建内存工作空间，将数据保存在内存中
        /// </summary>
        public static IWorkspace GetWorkspace()
        {
            IWorkspaceFactory workspaceFactory = new InMemoryWorkspaceFactoryClass();
            IWorkspaceName workspaceName = workspaceFactory.Create(null, "MyWorkspace", null, 0);
            IName name = (IName)workspaceName;
            IWorkspace workspace = (IWorkspace)name.Open();
            return workspace;
        }

根据指定类型获取或创建要素类

        /// <summary>
        /// 根据类型名称获取要素类，如果不存在则创建一个该类型的要素类
        /// </summary>
        /// <param name="workspace">工作空间</param>
        /// <param name="spatialReference">空间参照</param>
        /// <param name="fClsGeoType">要素类几何类型名称</param>
        /// <returns></returns>
        private static IFeatureClass GetFeatureClass(IWorkspace workspace, ISpatialReference spatialReference, string fClsGeoType)
        {
            IFeatureWorkspace featureWorkspace = workspace as IFeatureWorkspace;
            IFeatureClass featureClass = null;
            try
            {
                featureClass = featureWorkspace.OpenFeatureClass(fClsGeoType);
                return featureClass;
            }
            catch
            {
            }
            UID CLSEXT = null;
            UID CLSID = new UIDClass();
            CLSID.Value = "esriGeoDatabase.Feature";
            string strConfigKeyword = "";
            IGeometryDef pGeometryDef = new GeometryDefClass();
            IGeometryDefEdit geometryDefEdit = pGeometryDef as IGeometryDefEdit;
            geometryDefEdit.GridCount_2 = 1; // 设置空间索引（个人数据库仅支持1个）
            geometryDefEdit.GeometryType_2 = GetEsriGeometryType(fClsGeoType); // 设置为几何类型
            geometryDefEdit.SpatialReference_2 = spatialReference;
            IFields fields = new FieldsClass();
            IFieldsEdit fieldsEdit = fields as IFieldsEdit;
            // 创建OBJECTID字段
            IField fieldOID = new Field();
            IFieldEdit fieldEditOID = fieldOID as IFieldEdit;
            fieldEditOID.Name_2 = "OBJECTID";
            fieldEditOID.AliasName_2 = "OBJECTID";
            fieldEditOID.Type_2 = esriFieldType.esriFieldTypeOID;
            fieldEditOID.Editable_2 = false;
            fieldsEdit.AddField(fieldOID);
            // 创建几何字段
            IField fieldShape = new Field();
            IFieldEdit fieldEditShape = fieldShape as IFieldEdit;
            fieldEditShape.Name_2 = "SHAPE";
            fieldEditShape.AliasName_2 = "SHAPE";
            fieldEditShape.Type_2 = esriFieldType.esriFieldTypeGeometry;
            fieldEditShape.GeometryDef_2 = pGeometryDef;
            fieldEditShape.Editable_2 = true;
            fieldsEdit.AddField(fieldShape);
            string strShapeField = fieldShape.Name;
            IFieldChecker fieldChecker = new FieldCheckerClass();
            fieldChecker.ValidateWorkspace = workspace;
            IEnumFieldError enumFieldError;
            IFields validatedFields;
            fieldChecker.Validate(fields, out enumFieldError, out validatedFields);
            featureClass = featureWorkspace.CreateFeatureClass(fClsGeoType, validatedFields, CLSID, CLSEXT, esriFeatureType.esriFTSimple, strShapeField, strConfigKeyword);
            return featureClass;
        }

获取线要素

        /// <summary>
        /// 创建一个新的线状符号，并将其加入点要素类中
        /// </summary>
        public static void CreateSimpleLine(IWorkspace workspace, IMap map, IPointCollection linePointCollection, IColor color, double width, esriSimpleLineStyle style)
        {
            // 创建线图形
            IPolyline pPolyline = linePointCollection as IPolyline;
            IGeometry polylineGeometry = pPolyline as IGeometry;
            ITopologicalOperator pTop = polylineGeometry as ITopologicalOperator;
            pTop.Simplify();
            // 获取线要素类并添加一个新的线要素
            IFeatureClass fCls = GetFeatureClass(workspace, map.SpatialReference, "esriSLS");
            IFeature pFeature = fCls.CreateFeature();
            pFeature.Shape = polylineGeometry;
            pFeature.Store();
            // 新建线要素图层
            IFeatureLayer featureLayer = new FeatureLayerClass();
            featureLayer.FeatureClass = fCls;
            IGeoFeatureLayer pGeoFeatLyr = featureLayer as IGeoFeatureLayer;
            // 设置线符号样式
            ISimpleLineSymbol pLineSymbol = new SimpleLineSymbolClass();
            pLineSymbol.Color = color;
            pLineSymbol.Width = width;
            pLineSymbol.Style = style;
            ISymbol symbol = pLineSymbol as ISymbol;
            // 更改线图层的样式（使之生效）
            ISimpleRenderer simpleRenderer = new SimpleRendererClass();
            simpleRenderer.Symbol = symbol;
            pGeoFeatLyr.Renderer = simpleRenderer as IFeatureRenderer;
            // 添加图层到地图中
            map.AddLayer(featureLayer as ILayer);
        }

小技巧

文本转枚举类型

（源代码来源于网络）

        /// <summary>
        /// 字符串转枚举类型
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="strType"></param>
        /// <returns></returns>
        public static T GetEnumType<T>(string strType)
        {
            T t = (T)Enum.Parse(typeof(T), strType);
            return t;
        }

获取RGB色彩

        /// <summary>
        /// 获取RGB色彩
        /// </summary>
        /// <param name="intR">红色值</param>
        /// <param name="intG">绿色值</param>
        /// <param name="intB">蓝色值</param>
        /// <param name="transparency">透明度</param>
        /// <returns>返回IRgbColor类型的值</returns>
        public static IRgbColor GetRgbColor(int intR, int intG, int intB, byte transparency)
        {
            IRgbColor pRgbColor = null;
            if (intR < 0 || intR > 255 || intG < 0 || intG > 255 || intB < 0 || intB > 255)
            {
                return pRgbColor;
            }
            pRgbColor = new RgbColorClass();
            pRgbColor.Red = intR;
            pRgbColor.Green = intG;
            pRgbColor.Blue = intB;
            pRgbColor.Transparency = transparency;
            return pRgbColor;
        }