VBA code to loop through directory getting only .dwg files

I need VBA code to loop through a directory and get only the .dwg files.  The code below will loop through the directory but it gets all file types.

Function GetAllFilesInDir(ByVal strDirPath As String) As Variant
    ' Loop through the directory specified in strDirPath and save each
    ' file name in an array, then return that array to the calling
    ' procedure.
    ' Return False if strDirPath is not a valid directory.
    Dim strTempName As String
    Dim varFiles() As Variant
    Dim lngFileCount As Long
   
    On Error GoTo GetAllFiles_Err
   
    ' Make sure that strDirPath ends with a "\" character.
    If Right$(strDirPath, 1) <> "\" Then
        strDirPath = strDirPath & "\"
    End If
   
    ' Make sure strDirPath is a directory.
    If GetAttr(strDirPath) = vbDirectory Then
        strTempName = Dir(strDirPath, vbDirectory)
        Do Until Len(strTempName) = 0
            ' Exclude ".", "..".
            If (strTempName <> ".") And (strTempName <> "..") Then
                ' Make sure we do not have a sub-directory name.
                If (GetAttr(strDirPath & strTempName) _
                    And vbDirectory) <> vbDirectory Then
                    ' Increase the size of the array
                    ' to accommodate the found filename
                    ' and add the filename to the array.
                    ReDim Preserve varFiles(lngFileCount)
                    varFiles(lngFileCount) = strTempName
                    lngFileCount = lngFileCount + 1
                End If
            End If
            ' Use the Dir function to find the next filename.
            strTempName = Dir()
        Loop
        ' Return the array of found files.
        GetAllFilesInDir = varFiles
    End If
GetAllFiles_End:
    Exit Function
GetAllFiles_Err:
    GetAllFilesInDir = False
    Resume GetAllFiles_End
End Function


Sub TestGetAllFiles()
    Dim varFileArray As Variant
    Dim lngI As Long
    Dim strDirName As String
   
   
    Const NO_FILES_IN_DIR As Long = 9
    Const INVALID_DIR As Long = 13
   
    On Error GoTo Test_Err
   
    strDirName = "E:\FSB\Plots"
    varFileArray = GetAllFilesInDir(strDirName)
    For lngI = 0 To UBound(varFileArray)
        Debug.Print varFileArray(lngI)
       
        Documents.Open strDirName & "\" & varFileArray(lngI)
            MsgBox "Name of this drawing is: " & ThisDrawing.Name
        ActiveDocument.Close , varFileArray(lngI)
       
    Next lngI