ジオメトリの不正の種類を判定

Dim pBoolean As Boolean
Dim reason As esriNonSimpleReasonEnum
Dim pTopologicalOperator As ITopologicalOperator3
Set pTopologicalOperator = pGeometry
pTopologicalOperator.IsKnownSimple = False
pBoolean = pTopologicalOperator.IsSimpleEx(reason)

'pBooleadn に不正かどうかが返される
'reason に不正の種類が返される