determine if checkbox on other application is checked

[Raouldukey]

I am writing a program to control other applications that are running. Essentially an automation UI program. I am using a combination of AutoIt and basic windows API calls (sendcommand). I am able to do almost everything that I need (read/write textboxes, labels, click buttons/checkboxes/radiobuttons) However, I cannot seem to work out how to determine if a radiobutton or checkbox is checked or not. I have searched and searched the web and cannot come up with an answer. I believe the Sendmessage(hWnd,BM_GetChecked,0,0) command will work with older Win32 controls, but only returns 0 with newer .NET controls. People talk about using Iaccessible interface, but I cannot figure out how to make it work, nor do I have the code for the other applications if I have to make changes there. So, I would greatly appreciate it if someone could put together a snippet of code that could identify if a checkbox/radiobutton is checked or not on a different application.

The following is what I have to determine the hWnd of the control and try to sendmessage to it. I can sendmessage(hWnd,BM_Click,0,0) just fine to click on it, but I cannot not determine if checked already.

I am not stuck on doing it this way at all if someone can show me another way to do it...

TIA

Public Class Form1

Declare Auto Function SendMessage2 Lib "user32.dll" Alias "SendMessageA" (ByVal hWnd As IntPtr, ByVal Msg As UInteger, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Int32

  

Private Declare Auto Function FindWindow Lib "user32.dll" ( _
ByVal lpClassName As String, _
ByVal lpWindowName As String _
) As IntPtr

    Private Declare Auto Function FindWindowEx Lib "user32.dll" ( _
    ByVal hwndParent As IntPtr, _
    ByVal hwndChildAfter As IntPtr, _
    ByVal lpszClass As String, _
    ByVal lpszWindow As String _
    ) As IntPtr


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
   
        Dim returnvalue As Integer

        Dim hWnd As IntPtr = FindWindow(vbNullString, "TestFormName")
        If hWnd.Equals(IntPtr.Zero) Then
            MessageBox.Show("no window")
            Return
        End If

       

        Dim hWndButton As IntPtr = _
        FindWindowEx(hWnd, IntPtr.Zero, "WindowsForms10.BUTTON.app.0.2bf8098_r20_ad1", "RadioButton1")
        If hWndButton.Equals(IntPtr.Zero) Then
            MessageBox.Show("no control")
            Return
        End If

        'once you have the right handle, try to send bm_click to see if checked
        
        returnvalue = SendMessage2(hWndButton, BM_GETCHECK, 0, 0)

     
        MessageBox.Show(CStr(returnvalue))



    End Sub


end class