iPhone 上的 USB 编程

iPhone 上的 USB 编程

swift
import UIKit
import ExternalAccessory
class ViewController: UIViewController, EAAccessoryDelegate, EASessionDelegate {
    var accessory: EAAccessory?
    var session: EASession?
    var inputStream: InputStream?
    var outputStream: OutputStream?
    override func viewDidLoad() {
        super.viewDidLoad()
        // 搜索可用的外部设备
        let accessories = EAAccessoryManager.shared().connectedAccessories
        for accessory in accessories {
            if accessory.protocolStrings.contains("com.example.protocol") {
                self.accessory = accessory
                break
            }
        }
        if let accessory = self.accessory {
            // 创建会话
            self.session = EASession(accessory: accessory, forProtocol: "com.example.protocol")
            if let session = self.session {
                // 打开输入和输出流
                self.inputStream = session.inputStream
                self.outputStream = session.outputStream
                self.inputStream?.delegate = self
                self.outputStream?.delegate = self
                self.inputStream?.schedule(in: .current, forMode: .default)
                self.outputStream?.schedule(in: .current, forMode: .default)
                self.inputStream?.open()
                self.outputStream?.open()
            }
        }
    }
    // 数据传输示例
    func sendData(data: Data) {
        if let outputStream = self.outputStream {
            let bytesWritten = outputStream.write(data, maxLength: data.count)
            if bytesWritten == -1 {
                // 发送失败
                print("Send data failed")
            }
        }
    }
    // 读取数据示例
    func readData() -> Data? {
        guard let inputStream = self.inputStream else {
            return nil
        }
        var buffer = [UInt8](repeating: 0, count: 1024)
        let bytesRead = inputStream.read(&buffer, maxLength: buffer.count)
        if bytesRead < 0 {
            // 读取失败
            return nil
        }
        return Data(bytes: buffer, count: bytesRead)
    }
    // 断开连接
    func disconnect() {
        self.inputStream?.close()
        self.outputStream?.close()
        self.inputStream?.remove(from: .current, forMode: .default)
        self.outputStream?.remove(from: .current, forMode: .default)
        self.inputStream?.delegate = nil
        self.outputStream?.delegate = nil
        self.inputStream = nil
        self.outputStream = nil
        self.session = nil
        self.accessory = nil
    }
    // EASessionDelegate 回调方法
    func session(_ session: EASession, didReceive data: Data) {
        // 处理接收到的数据
    }
    func session(_ session: EASession, didFailWithError error: Error) {
        // 处理错误
    }
}