public string ApplicationId { get; set; }

Public Property ApplicationId As String
	Get
	Set

public:
property String^ ApplicationId {
	String^ get ();
	void set (String^ value);
}

The creating application may use any text string as appropriate for its purposes, or leave this property unset. One option is to use Application.ActiveAddInId for a unique application id, or concatenate it with an application name for a more informative, but still unique id.