Arcengine创建内存工作空间，要素类（InMemoryWorkspaceFactory）

1.创建内存工作空间

public static IWorkspace CreateInMemoryWorkspace()
{
  // Create an in-memory workspace factory.
  Type factoryType = Type.GetTypeFromProgID(
    "esriDataSourcesGDB.InMemoryWorkspaceFactory");
  IWorkspaceFactory workspaceFactory = (IWorkspaceFactory)
    Activator.CreateInstance(factoryType);

  // Create an in-memory workspace.
  IWorkspaceName workspaceName = workspaceFactory.Create("", "MyWorkspace",
    null, 0);

  // Cast for IName and open a reference to the in-memory workspace through the name object.
  IName name = (IName)workspaceName;
  IWorkspace workspace = (IWorkspace)name.Open();
  return workspace;
}

2.创建要素类

    /// <summary>
        /// 在指定的数据库中创建与源要素类相同的要素类
        /// </summary>
        /// <param name="pWorkspace"></param>
        /// <param name="pSrcFC"></param>
        /// <param name="sTargetName"></param>
        /// <param name="pTargetSrf"></param>
        /// <param name="sOutputFields"></param>
        /// <returns></returns>
        public static IFeatureClass CreateFeatureClass(IWorkspace pWorkspace,
            IFeatureClass pSrcFC,
            string sTargetName = null,
            ISpatialReference pTargetSrf = null,
            string sOutputFields = null)
        {
            if (string.IsNullOrEmpty(sTargetName))
            {
                sTargetName = (pSrcFC as IDataset).Name;
            }
            sTargetName = GetDatasetName(sTargetName);
            DeleteDataset(pWorkspace, sTargetName);
            //验证字段
            IFields pFields;
            string sShapeFieldName;
            string sError;
            CheckFields(pSrcFC, pWorkspace, out pFields, out sShapeFieldName, out sError);
            //根据输出字段限制，处理字段
            if (!string.IsNullOrWhiteSpace(sOutputFields))
            {
                IFieldsEdit pFieldsEdit = pFields as IFieldsEdit;
                string[] pOutputFields = sOutputFields.Split(',');
                for (int i = pFields.FieldCount - 1; i >= 0; i--)
                {
                    IField pField = pFields.get_Field(i);
                    if (pField.Type == esriFieldType.esriFieldTypeGeometry ||
                        pField.Type == esriFieldType.esriFieldTypeOID)
                    {
                        continue;
                    }
                    bool bFind = false;
                    foreach (string sOutputField in pOutputFields)
                    {
                        if (sOutputField == pField.Name)
                        {
                            bFind = true;
                            break;
                        }
                    }
                    if (!bFind)
                    {
                        pFieldsEdit.DeleteField(pField);
                    }
                }
            }

            //修改几何字段中的空间参考信息
            if (pTargetSrf != null)
            {
                int iIndex = pFields.FindField(sShapeFieldName);
                //几何定义
                IGeometryDef pGeometryDef = pFields.get_Field(iIndex).GeometryDef;
                IGeometryDefEdit pGeometryDefEdit = pGeometryDef as IGeometryDefEdit;
                pGeometryDefEdit.SpatialReference_2 = pTargetSrf;
            }

            IFeatureClass pFeatureClass = CreateFeatureClass(pWorkspace, pSrcFC,
                pFields, sShapeFieldName, sTargetName, null, pTargetSrf);
            return pFeatureClass;
        }

        /// <summary>
        /// 创建要素类，考虑要素类存在要素数据集中
        /// </summary>
        /// <param name="pWorkspace"></param>
        /// <param name="pSrcFC"></param>
        /// <param name="pFields"></param>
        /// <param name="sShapeFieldName"></param>
        /// <param name="sTargetName"></param>
        /// <param name="sAlias"></param>
        /// <param name="pTargetSrf"></param>
        /// <returns></returns>
        public static IFeatureClass CreateFeatureClass(IWorkspace pWorkspace,
            IFeatureClass pSrcFC,
            IFields pFields,
            string sShapeFieldName,
            string sTargetName = null,
            string sAlias = null,
            ISpatialReference pTargetSrf = null)
        {
            UID CLSID = new UIDClass();
            CLSID.Value = "esriGeoDatabase.Feature";

            if (string.IsNullOrEmpty(sTargetName))
            {
                sTargetName = GetDatasetName((pSrcFC as IDataset).Name);
            }
            IFeatureClass pFeatureClass = null;
            //是否需要创建要素数据集
            IFeatureDataset pTargetDataset = GetFeatureDataset(pWorkspace, pSrcFC, pTargetSrf);
            try
            {
                if (pSrcFC.FeatureType == esriFeatureType.esriFTAnnotation)
                {
                    //Anno Workspace
                    IFeatureWorkspaceAnno pFWSAnno = pWorkspace as IFeatureWorkspaceAnno;
                    //获得AnnoFeatureClass的显示参数units和referencescale
                    IAnnoClass pAnnoClass = pSrcFC.Extension as IAnnoClass;

                    IGraphicsLayerScale pGraphicsLayerScale = new GraphicsLayerScaleClass();
                    pGraphicsLayerScale.Units = pAnnoClass.ReferenceScaleUnits;
                    pGraphicsLayerScale.ReferenceScale = pAnnoClass.ReferenceScale;

                    IObjectClassDescription pOCDesc = new AnnotationFeatureClassDescription();
                    pFeatureClass = pFWSAnno.CreateAnnotationClass(sTargetName, pFields, pOCDesc.InstanceCLSID,
                        pOCDesc.ClassExtensionCLSID, pSrcFC.ShapeFieldName, "", pTargetDataset,
                        null, pAnnoClass.AnnoProperties, pGraphicsLayerScale,
                        pAnnoClass.SymbolCollection, false);
                }
                else
                {
                    if (pTargetDataset != null)
                    {
                        pFeatureClass = pTargetDataset.CreateFeatureClass(sTargetName, pFields, CLSID, null, pSrcFC.FeatureType, sShapeFieldName, "");
                    }
                    else
                    {
                        pFeatureClass = (pWorkspace as IFeatureWorkspace).CreateFeatureClass(sTargetName, pFields, CLSID, null, pSrcFC.FeatureType, sShapeFieldName, "");
                    }
                }
            }
            finally
            {
                if (pTargetDataset != null)
                {
                    Marshal.ReleaseComObject(pTargetDataset);
                }
            }
            //设置要素类别名
            if (string.IsNullOrWhiteSpace(sAlias))
            {
                sAlias = pSrcFC.AliasName;
            }
            AlterDatasetAlias(pFeatureClass, sAlias);
            return pFeatureClass;
        }

转载自：https://blog.csdn.net/kone0611/article/details/73023108