1.建立空間參考

        /// <summary>
        /// 根據prj檔案建立空間參考
        /// </summary>
        /// <param name="strProFile">空間參照檔案</param>
        /// <returns></returns>
        public static ISpatialReference CreateSpatialReference(string strProFile)
        {
            ISpatialReferenceFactory pSpatialReferenceFactory = new SpatialReferenceEnvironmentClass();
            ISpatialReference pSpatialReference = pSpatialReferenceFactory.CreateESRISpatialReferenceFromPRJFile(strProFile);
            return pSpatialReference;           
        }
 

        /// <summary>
        /// 建立地理座標系
        /// </summary>
        /// <param name="gcType">esriSRProjCS4Type</param>
        /// <returns></returns>
        public static ISpatialReference CreateGeographicCoordinate(esriSRProjCS4Type gcsType)
        {
            ISpatialReferenceFactory pSpatialReferenceFactory = new SpatialReferenceEnvironmentClass();
            ISpatialReference pSpatialReference = pSpatialReferenceFactory.CreateGeographicCoordinateSystem((int)gcsType);
            return pSpatialReference;
        }
 

        /// <summary>
        /// 建立投影座標系
        /// </summary>
        /// <param name="pcType">esriSRProjCS4Type</param>
        /// <returns></returns>
        public static ISpatialReference CreateProjectedCoordinate(esriSRProjCS4Type pcsType)
        {
            ISpatialReferenceFactory2 pSpatialReferenceFactory = new SpatialReferenceEnvironmentClass();
            ISpatialReference pSpatialReference = pSpatialReferenceFactory.CreateProjectedCoordinateSystem((int)pcsType);
            return pSpatialReference;
        }
 

        /// <summary>
        /// 獲取空投影
        /// </summary>
        /// <returns></returns>
        public static ISpatialReference CreateUnKnownSpatialReference()
        {
            ISpatialReference pSpatialReference = new UnknownCoordinateSystemClass();
            pSpatialReference.SetDomain(0, 99999999, 0, 99999999);//設定空間範圍
            return pSpatialReference;
        }

2.獲取空間參考

        /// <summary>
        /// 獲取要素集空間參考
        /// </summary>
        /// <param name="pFeatureDataset">要素集</param>
        /// <returns></returns>
        public static ISpatialReference GetSpatialReference(IFeatureDataset pFeatureDataset)
        {
            IGeoDataset pGeoDataset = pFeatureDataset as IGeoDataset;
            ISpatialReference pSpatialReference = pGeoDataset.SpatialReference;
            return pSpatialReference;           
        }

        /// <summary>
        /// 獲取要素層空間參考
        /// </summary>
        /// <param name="pFeatureLayer">要素層</param>
        /// <returns></returns>
        public static ISpatialReference GetSpatialReferenc(IFeatureLayer pFeatureLayer)
        {IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;
            IGeoDataset pGeoDataset = pFeatureClass as IGeoDataset;
            ISpatialReference pSpatialReference = pGeoDataset.SpatialReference;
            return pSpatialReference;           
        }

        /// <summary>
        /// 獲取要素類空間參考
        /// </summary>
        /// <param name="pFeatureClass">要素類</param>
        /// <returns></returns>
        public static ISpatialReference GetSpatialReference(IFeatureClass pFeatureClass)
        {
            IGeoDataset pGeoDataset = pFeatureClass as IGeoDataset;
            ISpatialReference pSpatialReference = pGeoDataset.SpatialReference;
            return pSpatialReference;           
        }

3.修改空間參考

        /// <summary>
        /// 修改要素集空間參考
        /// </summary>
        /// <param name="pFeatureDataset">要素集</param>
        /// <param name="pSpatialReference">新空間參考</param>
        public static void AlterSpatialReference(IFeatureDataset pFeatureDataset, ISpatialReference pSpatialReference)
        {
            IGeoDataset pGeoDataset = pFeatureDataset as IGeoDataset;
            IGeoDatasetSchemaEdit pGeoDatasetSchemaEdit = pGeoDataset as IGeoDatasetSchemaEdit;
            if (pGeoDatasetSchemaEdit.CanAlterSpatialReference == true)
                pGeoDatasetSchemaEdit.AlterSpatialReference(pSpatialReference);
        }

        /// <summary>
        /// 修改要素類空間參考
        /// </summary>
        /// <param name="pFeatureClass">要素類</param>
        /// <param name="pSpatialReference">新空間參考</param>
        public static void AlterSpatialReference(IFeatureClass pFeatureClass, ISpatialReference pSpatialReference)
        {
            IGeoDataset pGeoDataset = pFeatureClass as IGeoDataset;
            IGeoDatasetSchemaEdit pGeoDatasetSchemaEdit = pGeoDataset as IGeoDatasetSchemaEdit;
            if (pGeoDatasetSchemaEdit.CanAlterSpatialReference == true)
                pGeoDatasetSchemaEdit.AlterSpatialReference(pSpatialReference);
        }