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C#使用PuppeteerSharp庫的示例代碼

更新時間：2023年12月07日 09:38:55 作者：rjcql

PuppeteerSharp 是一個用于在 .NET 平臺上控制無頭（Headless） Chrome 瀏覽器的庫,本文主要為大家詳細(xì)介紹了C#中使用PuppeteerSharp庫的工具類,需要的可以了解下

寫在前面

類庫介紹：PuppeteerSharp 是一個用于在 .NET 平臺上控制無頭（Headless） Chrome 瀏覽器的庫。它允許開發(fā)者通過編程方式模擬瀏覽器行為，執(zhí)行網(wǎng)頁操作，截取網(wǎng)頁截圖，獲取網(wǎng)頁內(nèi)容，可以把網(wǎng)頁轉(zhuǎn)換成PDF等等。PuppeteerSharp 是 Puppeteer 在 .NET 環(huán)境中的等效實現(xiàn)，Puppeteer 是由 Google 提供的一個用于控制無界面瀏覽器 Chrome 的工具。

老規(guī)矩通過NuGet進(jìn)行安裝

代碼實現(xiàn)

        public static async void DoScreenshot(string url)
        {
            using var browserFetcher = new BrowserFetcher();
            await browserFetcher.DownloadAsync();
            await using var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = true });
            await using var page = await browser.NewPageAsync();
            await page.SetViewportAsync(new ViewPortOptions
            {
                Width = 1920,
                Height = 1080
            });
            await page.GoToAsync(url);
            var picPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "test.jpg");
            await page.ScreenshotAsync(picPath);
            await browser.CloseAsync();
        }
 
        public static async void ExportAsPdf(string url)
        { 
            using var browserFetcher = new BrowserFetcher();
            await browserFetcher.DownloadAsync();
            await using var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = true });
            await using var page = await browser.NewPageAsync();
            await page.GoToAsync(url);
            //等待字體加載完畢
            await page.EvaluateExpressionHandleAsync("document.fonts.ready");
            var pdfPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "test.pdf");
            await page.PdfAsync(pdfPath);
            await browser.CloseAsync();
        }
 
        public static async void FetchUrls(string url)
        {
            //瀏覽器配置
            var options = new LaunchOptions { Headless = true };
            await new BrowserFetcher().DownloadAsync();
 
            //打開瀏覽器
            using (var browser = await Puppeteer.LaunchAsync(options))
            using (var page = await browser.NewPageAsync())
            {
                //加載頁面
                await page.GoToAsync(url);
                var urlList = new List<string>();
                //獲取所有超鏈接
                var jsSelectAllAnchors = @"Array.from(document.querySelectorAll('a')).map(a => a.href);";
                var urls = await page.EvaluateExpressionAsync<string[]>(jsSelectAllAnchors);
                foreach (string u in urls)
                {
                    urlList.Add($"Url: {u}");
                }
                var urlPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "urls.txt");
                File.WriteAllLines(urlPath, urlList);
                await browser.CloseAsync();
            }
        }
 
 
        public static async void SearchTest(string url)
        {
            using var browserFetcher = new BrowserFetcher();
            await browserFetcher.DownloadAsync();
            await using var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = true });
            await using var page = await browser.NewPageAsync();
            await page.SetViewportAsync(new ViewPortOptions
            {
                Width = 1920,
                Height = 1080,
                //Devtools = true // 啟用 Chrome DevTools,無頭配置將自動禁用
            });
 
            //load: window.onload事件被觸發(fā)時候完成導(dǎo)航,某些情況下它根本不會發(fā)生。
            //domcontentloaded: Domcontentloaded事件觸發(fā)時候認(rèn)為導(dǎo)航成功
            //networkidle0: 在 500ms 內(nèi)沒有網(wǎng)絡(luò)連接時就算成功(全部的request結(jié)束),才認(rèn)為導(dǎo)航結(jié)束
            //networkidle2: 500ms 內(nèi)有不超過 2 個網(wǎng)絡(luò)連接時就算成功(還有兩個以下的request),就認(rèn)為導(dǎo)航完成
            //加載時長 networkidle0 > networkidle2 > load > domcontentloaded 
            //await page.GoToAsync(url, new NavigationOptions() { WaitUntil = new WaitUntilNavigation[] { WaitUntilNavigation.Networkidle0 } });
 
            // 跟蹤日志
            //await page.Tracing.StartAsync(new TracingOptions { Path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory,"race.json") });
            //await page.Tracing.StopAsync();
 
            await page.GoToAsync(url);
            await page.WaitForSelectorAsync(".searchbox input");
            await page.FocusAsync(".searchbox input"); // 聚焦
            await page.Keyboard.TypeAsync("CN Tower, Toronto, Ontario, Canada"); // 鍵盤輸入
            await page.ClickAsync(".searchIcon"); // 點擊
            await page.WaitForNavigationAsync();
            var content = await page.GetContentAsync();
 
            // 下載配置
            //var cdp = await page.Target.CreateCDPSessionAsync();
            //await cdp.SendAsync("Page.setDownloadBehavior", new
            //{
            //    behavior = "allow",
            //    downloadPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "testing_downloads")
            //});
            //await cdp.DetachAsync();
        }

調(diào)用示例

PuppeteerHelper.DoScreenshot("https://www.baidu.com/");
PuppeteerHelper.ExportAsPdf("https://www.baidu.com/");
PuppeteerHelper.FetchUrls("https://www.baidu.com/");

執(zhí)行結(jié)果如下：