如何在下载本地文件(不在捆绑包中)后在WKWebView中加载本地文件，并在url中使用参数？

import UIKit
import WebKit

class ViewController: UIViewController, WKNavigationDelegate {
    var webView: WKWebView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建WKWebView
        webView = WKWebView(frame: view.bounds)
        webView.navigationDelegate = self
        view.addSubview(webView)
        
        // 下载文件到本地路径
        let fileURL = downloadFile()
        
        // 创建带有参数的URL
        let urlWithParams = addParamsToURL(fileURL, params: ["param1": "value1", "param2": "value2"])
        
        // 加载本地文件
        let request = URLRequest(url: urlWithParams)
        webView.load(request)
    }
    
    // 下载文件到本地路径
    func downloadFile() -> URL {
        // 下载文件的URL
        let fileURL = URL(string: "https://example.com/path/to/file")!
        
        // 下载文件并保存到本地路径
        let destinationURL = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!.appendingPathComponent("file.pdf")
        try? FileManager.default.removeItem(at: destinationURL)
        try? FileManager.default.copyItem(at: fileURL, to: destinationURL)
        
        return destinationURL
    }
    
    // 创建带有参数的URL
    func addParamsToURL(_ url: URL, params: [String: String]) -> URL {
        var components = URLComponents(url: url, resolvingAgainstBaseURL: false)!
        var queryItems = [URLQueryItem]()
        
        for (key, value) in params {
            queryItems.append(URLQueryItem(name: key, value: value))
        }
        
        components.queryItems = queryItems
        return components.url!
    }
    
    // WKWebView导航完成时调用
    func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        // 网页加载完成
    }
}