CAD2GIS:arcengine注记添加

在做CAD注记转GIS注记，坎坷，百度了几乎所有可能的资料。

主要参照这里的方法（c++）。我使用C#重写了，均测试通过。

http://www.cnblogs.com/junyuz/archive/2011/09/01/2162625.html

重要提示：

       必须创建好注记图层，设置好比例尺和坐标系。困在这里两天没通过。

方法一 通过IFDOGraphicsLayer添加Elements的方式实现

        /// <summary>
        /// 添加到注记图层
        /// </summary>
        /// <param name="pFeatCls">注记图层</param>
        /// <param name="pGeometry">插入的位置:一般是一个IPoint</param>
        /// <returns></returns>
        protected bool InsertAnnoFea(IFeatureClass pFeatCls, IGeometry pGeometry)
        {

            IFeatureClass annocls = pFeatCls;
            IDataset pDataset = annocls as IDataset;
            ITransactions pTransactions = pDataset.Workspace as ITransactions;
            pTransactions.StartTransaction();
            IFDOGraphicsLayerFactory pFDOGLFactory = new FDOGraphicsLayerFactoryClass();
            ILayer tmpLayer = pFDOGLFactory.OpenGraphicsLayer(pDataset.Workspace as IFeatureWorkspace, annocls.FeatureDataset, pDataset.Name);
            IFDOGraphicsLayer pFDOGLayer = tmpLayer as IFDOGraphicsLayer;
            IElementCollection pElementColl = new ElementCollectionClass();

            pFDOGLayer.BeginAddElements();
            ITextElement pTextElement = AnnoUtil.MakeTextElement(text, dHSize, rgbColor, sHFont, dHAngle) as ITextElement;
            IElement pElement = pTextElement as IElement;
            pElement.Geometry = pGeometry;

            pElementColl.Add(pElement, 0);

            pFDOGLayer.DoAddElements(pElementColl, 0);
            pFDOGLayer.EndAddElements();

            pElementColl.Clear();
            pTransactions.CommitTransaction();

            return true;
        }

方法二 通过IAnnotationFeature来实现

        /// <summary>
        /// 添加到注记图层
        /// </summary>
        /// <param name="pFeatCls">注记图层</param>
        /// <param name="pGeometry">插入的位置:一般是一个IPoint</param>
        /// <returns></returns>
        protected bool InsertAnnoFea2(IFeatureClass pFeatCls, IGeometry pGeometry)
        {
            IFeatureClass annocls = pFeatCls;
            IWorkspace workspace = ((IDataset)annocls).Workspace;
            IWorkspaceEdit workspaceEdit = workspace as IWorkspaceEdit;
            bool startEdit = workspaceEdit.IsBeingEdited();
            if (!startEdit)
            {
                workspaceEdit.StartEditing(false);
            }
            workspaceEdit.StartEditOperation();

            ITextElement pTextElement = AnnoUtil.MakeTextElement(text, dHSize, rgbColor, sHFont, dHAngle) as ITextElement;
            IElement pElement = pTextElement as IElement;
            pElement.Geometry = pGeometry;

            IFeature pFeature = annocls.CreateFeature();

            IAnnotationFeature pAnnoFeature = pFeature as IAnnotationFeature;
            pAnnoFeature.Annotation = pElement;
            pFeature.Store();

            workspaceEdit.StopEditOperation();
            workspaceEdit.StopEditing(true);
            return true;
        }

junyuz：这两种方法，经过实际测试都可以成功，在导入的时候还需要注意一下空间参考系的问题，需要对应上，特别要注意dwg中的数据是否正确，如果注记的坐标不在参考系范围内，会出现导入失败的现象，我就是因为这个低级的错误，纠结了两天。

ps. MakeTextElement是创建ITextElement的方法。