IARPageLayout.ARMapCount Property

The number of maps in the page layout's map collection.

[Visual Basic 6.0]
Property ARMapCount As Long

[Visual Basic .NET]
Public ReadOnly Property ARMapCount As Integer

[C#]
public int ARMapCount {get;}

Available with ArcGIS Desktop. Requires Publisher Extension.

The ARMapCount property returns the number of ARMap's within the ARPageLayout.

EDN: ESRI Developer Network