如何将相机/照片库中的图像保存到要在UICollectionView中显示的数组中

import UIKit
import AVFoundation
import Photos

class ViewController: UIViewController, AVCapturePhotoCaptureDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate {

    var imageArray: [UIImage] = []
    
    // 拍摄照片
    func capturePhoto() {
        let captureSession = AVCaptureSession()
        guard let captureDevice = AVCaptureDevice.default(for: .video) else { return }
        
        do {
            let input = try AVCaptureDeviceInput(device: captureDevice)
            captureSession.addInput(input)
            
            let photoOutput = AVCapturePhotoOutput()
            captureSession.addOutput(photoOutput)
            
            captureSession.startRunning()
            
            let settings = AVCapturePhotoSettings()
            photoOutput.capturePhoto(with: settings, delegate: self)
        } catch {
            print(error)
        }
    }
    
    // AVCapturePhotoCaptureDelegate方法，拍摄照片完成后调用
    func photoOutput(_ output: AVCapturePhotoOutput, didFinishProcessingPhoto photo: AVCapturePhoto, error: Error?) {
        if let imageData = photo.fileDataRepresentation(), let image = UIImage(data: imageData) {
            imageArray.append(image)
        }
    }
    
    // 选择照片
    func selectPhoto() {
        let imagePicker = UIImagePickerController()
        imagePicker.delegate = self
        imagePicker.sourceType = .photoLibrary
        present(imagePicker, animated: true, completion: nil)
    }
    
    // UIImagePickerControllerDelegate方法，选择照片完成后调用
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        if let image = info[.originalImage] as? UIImage {
            imageArray.append(image)
        }
        
        picker.dismiss(animated: true, completion: nil)
    }
    
    // 在UICollectionView中显示图像
    // ...
}