透過以下方式可以取得FileManager搜尋程式中的檔案
let manager = FileManager.default
let urlForDocument = manager.urls(for: .documentDirectory, in:.userDomainMask)
let finalurl = urlForDocument.first! as URL
let contentsOfPath = try? manager.contentsOfDirectory(atPath: finalurl.path)
print("contentsOfPath: \(contentsOfPath)")