WebSession.HasPageNamed
From Xojo Documentation
Method
WebSession.HasPageNamed(pageName As String, implicitOnly As Boolean = False) As Boolean
New in 2020r1
Supported for all project types and targets.
New in 2020r1
Supported for all project types and targets.
Returns True if the pageName passed is currently instantiated within the current session. If implicitOnly is true then only implicit instances of pages are considered.