This method Refreshes the contents of the thumbnail collection. When the contents of a directory or multi-page image file have changed, Refresh can be used to update the items in the thumbnail collection. Refresh is limited in that it can only be used when a collection is created from a directory or a multi-page image file

public void Refresh()

public: void Refresh(); 

public:
void Refresh(); 

'Declaration
 
Public Sub Refresh() 

'Usage
 
Dim instance As ThumbnailItemCollection
 
instance.Refresh()