F# Code To Check For Connection Type With Xamarin.Android

CheckForConn.fs

open Android.App
open Android.Content
open Android.Net

let IsConnectionAvailable (app:Activity) connTypeToCheckFor =

    let n = app.GetSystemService(Context.ConnectivityService)
    
    let cm = 
        match n with 
        | :? ConnectivityManager as cm -> Some(cm)
        | null | _ -> None
    
    let cs = if cm.IsSome then Some(cm.Value.get_ActiveNetworkInfo()) else None
    
    if cs.IsSome then (cs.Value.Type = connTypeToCheckFor) else false 

(* Call this with code like this:

        // From inside of MainActivity type

        wifiStatus.Text <- sprintf "WiFi is %s" <| if IsConnectionAvailable this Android.Net.ConnectivityType.Wifi then "available" else "unavailable"

*)

(* Dave Thomas also suggested a few other alternative approaches for this:

let IsConnectionAvailable (app:Activity) connTypeToCheckFor =
      match app.GetSystemService(Context.ConnectivityService) with 
      | :? ConnectivityManager as cm -> (cm.get_ActiveNetworkInfo()).Type = connTypeToCheckFor
      | _ -> false

//Alternatively we could use an active pattern

let (|ConnectionAvailable|_|) connTypeToCheckFor (app:Activity) =
      match app.GetSystemService(Context.ConnectivityService) with 
      | :? ConnectivityManager as cm -> match cm.get_ActiveNetworkInfo() with
                                        | x when x.Type = connTypeToCheckFor -> Some()
                                        | _ -> None
      | _ -> None

// Then the check could then be parameterised:

  let text =  sprintf "WiFi is %s" <| match this with
                                      | ConnectionAvailable ConnectivityType.Wifi () ->  "available" 
                                      | _ -> "unavailable"


*)