gistfile1.txt

    private func testPrint() {
        let a4Document = Bundle.main.url(forResource: "testPrint", withExtension: "pdf")
        let airPrinter = UIPrinter(url: URL(string: printerUrl)!)
        
        // UIPrintInteractionController presents a user interface and manages the printing
        let printController = UIPrintInteractionController.shared
        let isPrintingAvailable = UIPrintInteractionController.isPrintingAvailable
        print("isPrintingAvailable : ", isPrintingAvailable)
        // PDF 內容
        printController.printingItem = a4Document
        print("aaa : ")
//        printController.print(to: airPrinter)
        // UIPrintInfo contains information about the print job
        let printInfo = UIPrintInfo(dictionary: nil)
        printInfo.outputType = .general
        printInfo.orientation = .portrait
        printInfo.duplex = UIPrintInfo.Duplex.none
        printInfo.duplex = .none
        printInfo.jobName = "myPrintJob"
        printController.printInfo = printInfo
        
        
        print("bbb : ")
        
        if let assignedPrintInfo = printController.printInfo {
            if assignedPrintInfo.duplex == UIPrintInfo.Duplex.none {
                print("printInfo 成功分配并且双面打印已禁用")
            } else {
                print("printInfo 分配失败或者双面打印没有被禁用")
            }
        } else {
            print("printInfo 分配失败")
        }
        
        airPrinter.contactPrinter { (available) -> Void in
            print("available : ", available)
            if (available) {
                printController.print(to: airPrinter, completionHandler: {a,b,c in
                    print("列印完成 a: ", a)
                    print("列印完成 b: ", b)
                    print("列印完成 c: ", c)
                })
            }
        }
        
    }