先安装PuppeteerSharp的库
然后调用如下方法

   private async Task ScreenShotAsync(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);
       await page.WaitForTimeoutAsync(1000);
       var viewportSize = await page.EvaluateExpressionAsync<dynamic>("({ width: window.innerWidth, height: window.innerHeight })");
       await page.ScreenshotAsync("test.png", new ScreenshotOptions()
       {
           Clip = new Clip
           {
               X = 0,
               Y = 0,
               Width = viewportSize.width,
               Height = viewportSize.height
           }
       });
   }

指定截图当前页内容，不滚动
如果想要截图所有的界面：

  await page.ScreenshotAsync("test.png", new ScreenshotOptions() { FullPage=true});