Here is how:
Public Sub ListFormControls()
Dim obj As Object
Dim frm As Form
Dim ctl As Control
For Each obj In Application.CurrentProject.AllForms
DoCmd.OpenForm obj.Name, acDesign, , , , acHidden
Set frm = Forms(obj.Name)
For Each ctl In frm.Controls
Debug.Print frm.Name, ctl.Name
Next
DoCmd.Close acForm, obj.Name, acSaveNo
Next
Set ctl = Nothing
Set frm = Nothing
Set obj = Nothing
End Sub