在Swift iOS中将PDF数据转换为UIImage并下载为相册

import UIKit
import PDFKit
import Photos

func convertPDFToImage(pdfData: Data) -> [UIImage]? {
    guard let pdf = PDFDocument(data: pdfData) else {
        return nil
    }
    
    var images: [UIImage] = []
    
    for pageIndex in 0..<pdf.pageCount {
        guard let page = pdf.page(at: pageIndex) else {
            continue
        }
        
        let pageSize = page.bounds(for: .mediaBox)
        let renderer = UIGraphicsImageRenderer(size: pageSize)
        
        let image = renderer.image { context in
            UIColor.white.set()
            context.fill(pageSize)
            
            context.cgContext.translateBy(x: 0.0, y: pageSize.height)
            context.cgContext.scaleBy(x: 1.0, y: -1.0)
            
            page.draw(with: .mediaBox, to: context.cgContext)
        }
        
        images.append(image)
    }
    
    return images
}

if let pdfData = try? Data(contentsOf: pdfURL), let images = convertPDFToImage(pdfData: pdfData) {
    for (index, image) in images.enumerated() {
        UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
    }
}