Property AllowMultipleSelectOfSameEntity As Boolean

Dim instance As IPropertyManagerPageSelectionbox
Dim value As Boolean
 
instance.AllowMultipleSelectOfSameEntity = value
 
value = instance.AllowMultipleSelectOfSameEntity

bool AllowMultipleSelectOfSameEntity {get; set;}

property bool AllowMultipleSelectOfSameEntity {
   bool get();
   void set (bool value);
}

Return Value

Id = ID_SELECTION2

            controlType = swControlType_Selectionbox

            caption = "Multi-Select"

            alignment = swControlAlign_Indent

            options = swControlOptions_Visible + swControlOptions_Enabled

            tip = "Select faces and vertices"

            Set swControl = m_Group1.AddControl(Id, controlType, caption, alignment, options, tip)

            If Not swControl Is Nothing Then

                Set m_Selection2 = swControl

                ' Both of the following properties must be set to

                ' allow multiple selections.

                ' Use the control key or the Append parameter in the

                ' appropriate Select method or IModelDocExtension::SelectById2

                ' to select multiple items in this selection box.

                m_Selection2.AllowMultipleSelectOfSameEntity = True

                m_Selection2.SingleEntityOnly = false

                filterArray(0) = swSelFACES

                filterArray(1) = swSelVERTICES

                m_Selection2.SetSelectionFilters (filterArray)

                m_Selection2.Height = 50

                m_Selection2.mark = 2

            End If

You can only use this method to set properties on the PropertyManager page before it is displayed or while it is closed. See IPropertyManagerPage2::Show2 and IPropertyManagerPage2::Close.