Topic: Collection Initialization

[kdub_nz]

Just a reminder regarding 'Collection Initialization'

Code - C#: [Select]

1.                         DBObjectCollection acDBObjColl = new DBObjectCollection();
2.                         acDBObjColl.Add(acLine1);
3.                         acDBObjColl.Add(acLine2);
4.                         acDBObjColl.Add(acCirc2);
5.                         acDBObjColl.Add(acMText4);
6.  

Since c#6 Can become

Code - C#: [Select]

1.                         DBObjectCollection acDBObjColl = new DBObjectCollection
2.                         {
3.                             acLine1,
4.                             acLine2,
5.                             acCirc2,
6.                             acMtext4
7.                         };
8.  

We can also use it when constructing in a using statement :
but I think it could lead to confusion, so I won't use it.

Code - C#: [Select]

1.     // Create a circle that is at 2,3 with a radius of 4.25
2.     using (Circle acCirc = new Circle
3.     {
4.         Center = new Point3d(2, 3, 0),
5.         Radius = 4.25
6.     })
7.     {
8.         // Add the new object to the block table record and the transaction
9.         acModelSpaceRec.AppendEntity(acCirc);
10.         acTrans.AddNewlyCreatedDBObject(acCirc, true);
11.  
12. < . . . . >
13.  

This compiles to the following. It's interesting how the compiler shuffles the (Decompiled/Reflected) code

Code - C#: [Select]

1. [CommandMethod("CopySingle")]
2. public static void CopySingle()
3. {
4.     Document document = Application.get_DocumentManager().get_MdiActiveDocument();
5.     Database database = document.get_Database();
6.     using (Transaction transaction = database.get_TransactionManager().StartTransaction())
7.     {
8.         BlockTableRecord record = transaction.GetObject((transaction.GetObject(database.get_BlockTableId(), 0)
9.                                                             as BlockTable).get_Item(BlockTableRecord.ModelSpace), 1)
10.                                                                  as BlockTableRecord;
11.         Circle circle1 = new Circle();
12.         circle1.set_Center(new Point3d(2.0, 3.0, 0.0));
13.         circle1.set_Radius(4.25);
14.         using (Circle circle = circle1)
15.         {
16.             record.AppendEntity(circle);
17.             transaction.AddNewlyCreatedDBObject(circle, true);
18.             Circle circle2 = circle.Clone() as Circle;
19.             circle2.set_Radius(1.0);
20.             record.AppendEntity(circle2);
21.             transaction.AddNewlyCreatedDBObject(circle2, true);
22.         }
23.        
24.         transaction.Commit();
25.     }
26. }
27.  
28.  

Coming back to this stuff I'm reminded of the axiom "use it or lose it"
... the wet grey stuff doesn't keep knowledge we don't use and reinforce  regularly.

[Atook]

Thanks kdub, a good reminder for me as well.