如何在swift中创建、写入和保存特定格式的pdf文件

import CoreGraphics

let pdfPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] + "/example.pdf"
guard let context = CGContext(url: URL(fileURLWithPath: pdfPath) as CFURL, mediaBox: nil, auxiliaryInfo: nil) else {
    return
}

context.beginPDFPage(nil)

// 设置字体
let font = UIFont.systemFont(ofSize: 12)
let attributes = [NSAttributedString.Key.font: font]

// 绘制文本
let text = "Hello, World!"
let attributedText = NSAttributedString(string: text, attributes: attributes)
let textRect = CGRect(x: 20, y: 20, width: 200, height: 20)
attributedText.draw(in: textRect)

// 绘制图像
let image = UIImage(named: "example.png")
let imageRect = CGRect(x: 20, y: 50, width: 100, height: 100)
image?.draw(in: imageRect)

context.endPDFPage()

context.closePDF()

let pdfPath = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0] + "/example.pdf"

let destinationPath = NSSearchPathForDirectoriesInDomains(.cachesDirectory, .userDomainMask, true)[0] + "/example.pdf"
try FileManager.default.copyItem(atPath: pdfPath, toPath: destinationPath)