hubFS: THE place for F#

(* Functions will appear in Excel as namespace.class_type

    Example :
        Namespace : AutomationAddin
        Class : MyFunctions
        Automation add-in : AutomationAddin.MyFunctions

 *)
namespace AutomationAddin

open System
open System.Runtime.InteropServices
open Microsoft.Win32

module Excel = Microsoft.Office.Interop.Excel

module Singleton =
begin
    let i = ref 0    
    let Count () = incr i ; !i
end

[< ClassInterface(ClassInterfaceType.AutoDual) ; ComVisible(true) >]
type MyFunctions =
class

    new()={}
       

(* Add-in Registration functions *)   

    static member GetSubKeyName (inType :Type ) =
        @"CLSID\{" + (inType.GUID.ToString()).ToUpper() + @"}\Programmable"

    [<ComRegisterFunctionAttribute>]
    static member RegisterFunction (inType :Type ) =
      Registry.ClassesRoot.CreateSubKey(MyFunctions.GetSubKeyName inType)
   

    [<ComUnregisterFunctionAttribute>]
    static member UnregisterFunction (inType :Type ) =
      Registry.ClassesRoot.DeleteSubKey(MyFunctions.GetSubKeyName inType, false)
   

(* Usable functions *)   

    member this.GetStars inN =
        let mutable sb = new System.Text.StringBuilder () in
        for i = 1 to inN do
            sb <- sb.Append("*")
        done ;
        sb.ToString ()
       
    member this.ToUpperCase (inString : String) =
        inString.ToUpper()
       
    member this.NumberOfCells (inRange : obj) =
        (inRange :?> Excel.Range).Cells.Count   

    member this.SumRange  (inRange : obj) =
        if inRange <> null then
            let r = inRange :?> Excel.Range in
            let mutable outTotal = 0.0 in
            for i = 1 to r.Rows.Count do
                for j = 1 to r.Columns.Count do
                    let c = r.Cells.Item(i, j) in
                    outTotal <- outTotal +. Convert.ToDouble ((c:?>Excel.Range).Value2)
                done
            done ;
            outTotal
        else failwith "ooops"
           
    member this.Area (inRange : obj) =
        let r : Excel.Range = inRange :?> Excel.Range in
        Convert.ToDouble (r.Width) *. Convert.ToDouble (r.Height)
           
    member this.SingletonCounter () = Singleton.Count ()

end