Unload all the PDF underlay

<?xml encoding=”UTF-8″>By Virupaksha Aithal

Below code shows the procedure to unload all the PDF underlays. It is required to update the corresponding PDF underlay references , so that AutoCAD can update the model space graphics. For this, the “PdfDefinition.GetPersistentReactorIds” API is used to get all the references of the PDF underlay definition.

[CommandMethod("PdfUnload")]
static public void PdfUnload()
{
Document doc = Application.DocumentManager.MdiActiveDocument;
Database db = doc.Database;
Editor ed = doc.Editor;
using (Transaction Tx = db.TransactionManager.StartTransaction())
{
DBDictionary nod = Tx.GetObject(db.NamedObjectsDictionaryId,
OpenMode.ForRead) as DBDictionary;
string defDictKey = UnderlayDefinition.GetDictionaryKey(typeof(PdfDefinition));
if (!nod.Contains(defDictKey))
return;
DBDictionary pdfDict = Tx.GetObject(nod.GetAt(defDictKey),
OpenMode.ForWrite) as DBDictionary;
foreach (DBDictionaryEntry entry in pdfDict)
{
PdfDefinition entryObj = Tx.GetObject(entry.Value,
OpenMode.ForWrite) as PdfDefinition;
entryObj.Unload();
ObjectIdCollection collection = entryObj.GetPersistentReactorIds();
foreach (ObjectId id in collection)
{
DBObject temObject = Tx.GetObject(id, OpenMode.ForRead);
if (temObject is PdfReference)
{
PdfReference pdfref = temObject as PdfReference;
pdfref.UpgradeOpen();
pdfref.RecordGraphicsModified(true);
}
}
}
Tx.Commit();
}
}