表格数据链接

CAD提供数据链接的功能，具体来说就是：将一个Excel的某一Sheet与CAD的某一表格关联起来。从而实现Excel表格转CAD表格的操作。
本文封装该接口。

链接Excel表格并插入CAD

重点在于数据链接的创建和绑定。

public static Table InsertExcelSheet0(this Document doc, string filePath, string sheetName, Point3d leftTopPoint, double tableWidth, string layoutName = null)
{
    if (doc == null) return null;
    Database db = doc.Database;
    Editor ed = doc.Editor;

    DataLinkManager dataLinkManager = db.DataLinkManager;
    const string dataLinkName = "从Excel导入表格";
    ObjectId dataLinkId = dataLinkManager.GetDataLink(dataLinkName);
    if (dataLinkId != ObjectId.Null)
        dataLinkManager.RemoveDataLink(dataLinkId);

    DataLink dataLink = new DataLink();
    dataLink.DataAdapterId = "AcExcel";
    dataLink.Name = dataLinkName;
    dataLink.Description = "Excel";
    dataLink.ConnectionString = filePath + "!" + sheetName;

    dataLinkId = dataLinkManager.AddDataLink(dataLink);

    Table table = null;
    using (Transaction transaction = db.TransactionManager.StartTransaction())
    {
        BlockTable bt = transaction.GetObject(db.BlockTableId, OpenMode.ForRead) as BlockTable;
        ObjectId spaceId = ObjectId.Null;
        if (layoutName == null)
            spaceId = bt[BlockTableRecord.ModelSpace];
        else
        {
            spaceId = GetLayoutIdByName(db, layoutName);
            if (spaceId == ObjectId.Null)
                return null;
        }
        BlockTableRecord btr = transaction.GetObject(spaceId, OpenMode.ForWrite) as BlockTableRecord;
        transaction.AddNewlyCreatedDBObject(dataLink, true);
        table = new Table();
        table.TableStyle = db.Tablestyle;
        table.Position = leftTopPoint;
        table.Cells[0, 0].DataLink = dataLinkId;
        table.GenerateLayout();
        btr.AppendEntity(table);
        transaction.AddNewlyCreatedDBObject(table, true);
        table.Width = tableWidth;
        table.Height = 1;
        transaction.Commit();
    }
    ed.Regen();
    return table;
}

插入链接表格并修改其文字样式

要修改链接表格的样式，必须先炸开表格再进行修改。

public static void InsertExcelSheetIntoCAD(this Document doc, string filePath, string sheetName, Point3d insertPoint, double tableWidth,out double tableHeight,string fontStyleName = "Standard", int textColorIndex = 3, int lineColorIndex = 3, string layoutName = null)
{
    tableHeight = 0.0;
    Database db = doc.Database;
    var table = doc.InsertExcelSheet0(filePath, sheetName, insertPoint, tableWidth, layoutName);
    if (table == null) return;
    
    var tablebox = table.GeometricExtents;
    tableHeight = tablebox.MaxPoint.Y - tablebox.MinPoint.Y;

    var styleId = db.GetTextStyleIdByName(fontStyleName, out double textSize, out double widthFactor);
    if (styleId == ObjectId.Null)
        return;

    using (Transaction transaction = doc.TransactionManager.StartTransaction())
    {
        DBObjectCollection objs = new DBObjectCollection();
        table.Explode(objs);
        List<Entity> entities = new List<Entity>();
        foreach (DBObject obj in objs)
        {
            if (obj is Entity)
            {
                var entity = (Entity)obj;
                if (entity is MText mText)
                {
                    DBObjectCollection childObjs = new DBObjectCollection();
                    mText.Explode(childObjs);

                    foreach (var childObj in childObjs)
                    {
                        if (childObj is DBText dbtext)
                        {
                            dbtext.TextString = dbtext.TextString.Trim();
                            dbtext.TextStyleId = styleId;
                            dbtext.ColorIndex = textColorIndex;
                            entities.Add(dbtext);
                        }
                    }
                }
                else
                {
                    entity.ColorIndex = lineColorIndex;
                    entities.Add(entity);
                }
            }
        }
        DwgPainter.DeleteEntity(db, table.ObjectId);
        DwgPainter.AddEntities(db, entities, layoutName);
        
        transaction.Commit();
    }
}