IMPLEMENTING ISELECTION INTERFACE FOR SECLECTING SOME SPECIFIC ELEMENTS IN VIEW

[AGYEMANG.OFOSU]

I am trying to select three different categories of elements using the iselectionfilter but my conditional clause to select beams in they normal to view is not working

public class Support : ISelectionFilter
		
			
											
			private bool IsEligibleSupport(Element element)
        		{
				BeamGeometry beamgeometry = new BeamGeometry(Doc);
				bool beamparallel=beamgeometry.IsParallelToView(Doc,element);
				int CategoryId= element.Category.Id.IntegerValue;
				
				if (CategoryId==(int)BuiltInCategory.OST_StructuralColumns|| 
				CategoryId==(int)BuiltInCategory.OST_Walls)
					if(CategoryId==(int)BuiltInCategory.OST_StructuralFraming && 
						beamparallel == true)
						return false;
				return true;												
        		}
			
			
			public bool AllowElement(Element ele)
			{				
				if(IsEligibleSupport(ele) )
					return true;
				return false;
					
			}
		
		
			public bool AllowReference(Reference r, XYZ point)
			{
				return true;
			}
			
		}

[jeremytammik · Accepted solution]

Here is a nice clean readable code snippet to check whether the category equals one of the target ones:

    public bool AllowElement( Element e )
    {
      bool rc = null != e.Category;
      if( rc )
      {
        int[] targets = new int[] {
          (int) BuiltInCategory.OST_StructuralColumns,
          (int) BuiltInCategory.OST_StructuralFraming,
          (int) BuiltInCategory.OST_Walls
        };

        int icat = e.Category.Id.IntegerValue;

        rc = targets.Any<int>( i => i.Equals(icat) );
      }
      return rc;
    }

It uses the System.Linq namespace.

You could avoid that by implementing your own comparison in a simple loop.

Cheers,

Jeremy