关键代码

import AVFoundation
//获取摄像设备
let device = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)
do {
    //创建输入,输出流
    let input = try AVCaptureDeviceInput.init(device: device)
    let output = AVCaptureMetadataOutput()
    output.rectOfInterest = CGRect(x: 0.1,y: 0,width: 0.9,height: 1)
    //设置代理,并且在主线程刷新
    output.setMetadataObjectsDelegate(self,queue: DispatchQueue.main)
    //初始化链接对象 / 高质量采集率
    session.canSetSessionPreset(AVCaptureSessionPresetHigh)
    session.addInput(input)
    session.addOutput(output)

    //先添加输入输出流,后设置支持的扫码所支持的格式,不然报错如下:Terminating app due to uncaught exception 'NSInvalidArgumentException',reason: '*** -[AVCaptureMetadataOutput setMetadataObjectTypes:] Unsupported type found - use -availableMetadataObjectTypes'
    //http://stackoverflow.com/questions/31063846/avcaptureMetadataoutput-setMetadataobjecttypes-unsupported-type-found
    //设置扫码支持的编码格式
    output.MetadataObjectTypes = [AVMetadataObjectTypeQRCode,AVMetadataObjectTypeEAN13Code,AVMetadataObjectTypeEAN8Code,AVMetadataObjectTypeCode128Code]

    let layer = AVCaptureVideoPreviewLayer(session: session)
    layer?.videoGravity = AVLayerVideoGravityResizeAspectFill
    layer?.frame = view.layer.bounds
    view.layer.insertSublayer(layer!,at: 0)
    //开始捕捉
    session.startRunning()

} catch let error as NSError  {
    print("errorInfo\(error.domain)")
}

/// 实现代理方法
extension ScanCodeController:AVCaptureMetadataOutputObjectsDelegate {
    func captureOutput(_ captureOutput: AVCaptureOutput!,didOutputMetadataObjects MetadataObjects: [Any]!,from connection: AVCaptureConnection!) {

        if MetadataObjects.count > 0 {
            session.stopRunning()
            let object = MetadataObjects[0]
            let string: String = (object as AnyObject).stringValue
            if let url = URL(string: string) {
            if UIApplication.shared.canOpenURL(url) {
                //去打开地址链接
                _ = self.navigationController?.popViewController(animated: true)
                UIApplication.shared.open(url)

            } else {
                //获取非链接结果
                let alertViewController = UIAlertController(title: "扫描结果",message: (object as AnyObject).stringValue,preferredStyle: .alert)
                let actionCancel = UIAlertAction(title: "退出",style: .cancel,handler: { (action) in
                    _ = self.navigationController?.popViewController(animated: true)
                })
                let actinSure = UIAlertAction(title: "再次扫描",style: .default,handler: { (action) in
                    self.session.startRunning()
                })
                alertViewController.addAction(actionCancel)
                alertViewController.addAction(actinSure)
                self.present(alertViewController,animated: true,completion: nil)
            }
            }
        }
    }
}

DEMO效果

DEMO下载地址