How to use EmulateMediaAsync method of PuppeteerSharp.Page class

Best Puppeteer-sharp code snippet using PuppeteerSharp.Page.EmulateMediaAsync

Page.cs

Source:Page.cs

...554        /// <seealso cref="GoToAsync(string, NavigationOptions)"/>555        public Task<Response> GoToAsync(string url, WaitUntilNavigation waitUntil)556            => GoToAsync(url, new NavigationOptions { WaitUntil = new[] { waitUntil } });557        /// <summary>558        /// generates a pdf of the page with <see cref="MediaType.Print"/> css media. To generate a pdf with <see cref="MediaType.Screen"/> media call <see cref="EmulateMediaAsync(MediaType)"/> with <see cref="MediaType.Screen"/>559        /// </summary>560        /// <param name="file">The file path to save the PDF to. paths are resolved using <see cref="Path.GetFullPath(string)"/></param>561        /// <returns></returns>562        /// <remarks>563        /// Generating a pdf is currently only supported in Chrome headless564        /// </remarks>565        public Task PdfAsync(string file) => PdfAsync(file, new PdfOptions());566        /// <summary>567        ///  generates a pdf of the page with <see cref="MediaType.Print"/> css media. To generate a pdf with <see cref="MediaType.Screen"/> media call <see cref="EmulateMediaAsync(MediaType)"/> with <see cref="MediaType.Screen"/>568        /// </summary>569        /// <param name="file">The file path to save the PDF to. paths are resolved using <see cref="Path.GetFullPath(string)"/></param>570        /// <param name="options">pdf options</param>571        /// <returns></returns>572        /// <remarks>573        /// Generating a pdf is currently only supported in Chrome headless574        /// </remarks>575        public async Task PdfAsync(string file, PdfOptions options)576            => await PdfInternalAsync(file, options).ConfigureAwait(false);577        /// <summary>578        /// generates a pdf of the page with <see cref="MediaType.Print"/> css media. To generate a pdf with <see cref="MediaType.Screen"/> media call <see cref="EmulateMediaAsync(MediaType)"/> with <see cref="MediaType.Screen"/>579        /// </summary>580        /// <returns>Task which resolves to a <see cref="Stream"/> containing the PDF data.</returns>581        /// <remarks>582        /// Generating a pdf is currently only supported in Chrome headless583        /// </remarks>584        public Task<Stream> PdfStreamAsync() => PdfStreamAsync(new PdfOptions());585        /// <summary>586        /// Generates a pdf of the page with <see cref="MediaType.Print"/> css media. To generate a pdf with <see cref="MediaType.Screen"/> media call <see cref="EmulateMediaAsync(MediaType)"/> with <see cref="MediaType.Screen"/>587        /// </summary>588        /// <param name="options">pdf options</param>589        /// <returns>Task which resolves to a <see cref="Stream"/> containing the PDF data.</returns>590        /// <remarks>591        /// Generating a pdf is currently only supported in Chrome headless592        /// </remarks>593        public async Task<Stream> PdfStreamAsync(PdfOptions options)594            => new MemoryStream(await PdfDataAsync(options).ConfigureAwait(false));595        /// <summary>596        /// Generates a pdf of the page with <see cref="MediaType.Print"/> css media. To generate a pdf with <see cref="MediaType.Screen"/> media call <see cref="EmulateMediaAsync(MediaType)"/> with <see cref="MediaType.Screen"/>597        /// </summary>598        /// <returns>Task which resolves to a <see cref="byte"/>[] containing the PDF data.</returns>599        /// <remarks>600        /// Generating a pdf is currently only supported in Chrome headless601        /// </remarks>602        public Task<byte[]> PdfDataAsync() => PdfDataAsync(new PdfOptions());603        /// <summary>604        /// Generates a pdf of the page with <see cref="MediaType.Print"/> css media. To generate a pdf with <see cref="MediaType.Screen"/> media call <see cref="EmulateMediaAsync(MediaType)"/> with <see cref="MediaType.Screen"/>605        /// </summary>606        /// <param name="options">pdf options</param>607        /// <returns>Task which resolves to a <see cref="byte"/>[] containing the PDF data.</returns>608        /// <remarks>609        /// Generating a pdf is currently only supported in Chrome headless610        /// </remarks>611        public Task<byte[]> PdfDataAsync(PdfOptions options) => PdfInternalAsync(null, options);612        internal async Task<byte[]> PdfInternalAsync(string file, PdfOptions options)613        {614            var paperWidth = PaperFormat.Letter.Width;615            var paperHeight = PaperFormat.Letter.Height;616            if (options.Format != null)617            {618                paperWidth = options.Format.Width;619                paperHeight = options.Format.Height;620            }621            else622            {623                if (options.Width != null)624                {625                    paperWidth = ConvertPrintParameterToInches(options.Width);626                }627                if (options.Height != null)628                {629                    paperHeight = ConvertPrintParameterToInches(options.Height);630                }631            }632            var marginTop = ConvertPrintParameterToInches(options.MarginOptions.Top);633            var marginLeft = ConvertPrintParameterToInches(options.MarginOptions.Left);634            var marginBottom = ConvertPrintParameterToInches(options.MarginOptions.Bottom);635            var marginRight = ConvertPrintParameterToInches(options.MarginOptions.Right);636            var result = await Client.SendAsync<PagePrintToPDFResponse>("Page.printToPDF", new PagePrintToPDFRequest637            {638                TransferMode = "ReturnAsStream",639                Landscape = options.Landscape,640                DisplayHeaderFooter = options.DisplayHeaderFooter,641                HeaderTemplate = options.HeaderTemplate,642                FooterTemplate = options.FooterTemplate,643                PrintBackground = options.PrintBackground,644                Scale = options.Scale,645                PaperWidth = paperWidth,646                PaperHeight = paperHeight,647                MarginTop = marginTop,648                MarginBottom = marginBottom,649                MarginLeft = marginLeft,650                MarginRight = marginRight,651                PageRanges = options.PageRanges,652                PreferCSSPageSize = options.PreferCSSPageSize653            }).ConfigureAwait(false);654            return await ProtocolStreamReader.ReadProtocolStreamByteAsync(Client, result.Stream, file).ConfigureAwait(false);655        }656        /// <summary>657        /// Enables/Disables Javascript on the page658        /// </summary>659        /// <returns>Task.</returns>660        /// <param name="enabled">Whether or not to enable JavaScript on the page.</param>661        public Task SetJavaScriptEnabledAsync(bool enabled)662        {663            if (enabled == JavascriptEnabled)664            {665                return Task.CompletedTask;666            }667            JavascriptEnabled = enabled;668            return Client.SendAsync("Emulation.setScriptExecutionDisabled", new EmulationSetScriptExecutionDisabledRequest669            {670                Value = !enabled671            });672        }673        /// <summary>674        /// Toggles bypassing page's Content-Security-Policy.675        /// </summary>676        /// <param name="enabled">sets bypassing of page's Content-Security-Policy.</param>677        /// <returns></returns>678        /// <remarks>679        /// CSP bypassing happens at the moment of CSP initialization rather then evaluation.680        /// Usually this means that <see cref="SetBypassCSPAsync(bool)"/> should be called before navigating to the domain.681        /// </remarks>682        public Task SetBypassCSPAsync(bool enabled) => Client.SendAsync("Page.setBypassCSP", new PageSetBypassCSPRequest683        {684            Enabled = enabled685        });686        /// <summary>687        /// Emulates a media such as screen or print.688        /// </summary>689        /// <returns>Task.</returns>690        /// <param name="media">Media to set.</param>691        [Obsolete("User EmulateMediaTypeAsync instead")]692        public Task EmulateMediaAsync(MediaType media) => EmulateMediaTypeAsync(media);693        /// <summary>694        /// Emulates a media such as screen or print.695        /// </summary>696        /// <param name="type">Media to set.</param>697        /// <example>698        /// <code>699        /// <![CDATA[700        /// await page.EvaluateFunctionAsync<bool>("() => matchMedia('screen').matches)");701        /// // â true702        /// await page.EvaluateFunctionAsync<bool>("() => matchMedia('print').matches)");703        /// // â true704        /// await page.EmulateMediaTypeAsync(MediaType.Print);705        /// await page.EvaluateFunctionAsync<bool>("() => matchMedia('screen').matches)");706        /// // â false...

Program.cs

Source:Program.cs

...45            if (!string.IsNullOrEmpty(options.WaitForSelector))46            {47                await page.WaitForSelectorAsync(options.WaitForSelector);48            }49            await page.EmulateMediaAsync(MediaType.Print);50            var pdfOptions = new PdfOptions51            {52                PrintBackground = options.PrintBackground,53                Landscape = options.Landscape54            };55            await page.PdfAsync(options.SavePath, pdfOptions);56        }57    }58}...

EmulateMediaTests.cs

Source:EmulateMediaTests.cs

...14        public async Task ShouldWork()15        {16            Assert.True(await Page.EvaluateExpressionAsync<bool>("window.matchMedia('screen').matches"));17            Assert.False(await Page.EvaluateExpressionAsync<bool>("window.matchMedia('print').matches"));18            await Page.EmulateMediaAsync(MediaType.Print);19            Assert.False(await Page.EvaluateExpressionAsync<bool>("window.matchMedia('screen').matches"));20            Assert.True(await Page.EvaluateExpressionAsync<bool>("window.matchMedia('print').matches"));21            await Page.EmulateMediaAsync(MediaType.None);22            Assert.True(await Page.EvaluateExpressionAsync<bool>("window.matchMedia('screen').matches"));23            Assert.False(await Page.EvaluateExpressionAsync<bool>("window.matchMedia('print').matches"));24        }25    }26}...

EmulateMediaAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            var browser = await Puppeteer.LaunchAsync(new LaunchOptions9            {10                Args = new string[] { "--start-maximized" }11            });12            var page = await browser.NewPageAsync();13            await page.EmulateMediaAsync(MediaType.Screen);14            await page.ScreenshotAsync("google.png");15            await browser.CloseAsync();16        }17    }18}

EmulateMediaAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);9            var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = false });10            var page = await browser.NewPageAsync();11            await page.EmulateMediaAsync(MediaType.Screen);12            Console.ReadLine();13        }14    }15}

EmulateMediaAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            {9            };10            using (var browser = await Puppeteer.LaunchAsync(options))11            {12                var page = await browser.NewPageAsync();13                await page.EmulateMediaAsync(new MediaFeature14                {15                });16            }17        }18    }19}

EmulateMediaAsync

Using AI Code Generation

1using System;2using System.IO;3using System.Threading.Tasks;4using PuppeteerSharp;5{6    {7        static async Task Main(string[] args)8        {9            var browser = await Puppeteer.LaunchAsync(new LaunchOptions10            {11            });12            var page = await browser.NewPageAsync();13            await page.EmulateMediaAsync(MediaType.Screen);14            await page.ScreenshotAsync("screen.png");15            await page.EmulateMediaAsync(MediaType.Print);16            await page.ScreenshotAsync("print.png");17            await browser.CloseAsync();18        }19    }20}

EmulateMediaAsync

Using AI Code Generation

1using System;2using System.Threading.Tasks;3using PuppeteerSharp;4{5    {6        static async Task Main(string[] args)7        {8            await new BrowserFetcher().DownloadAsync(BrowserFetcher.DefaultRevision);9            var browser = await Puppeteer.LaunchAsync(new LaunchOptions { Headless = false });10            var page = await browser.NewPageAsync();11            await page.EmulateMediaAsync(MediaType.Screen);12            await page.ScreenshotAsync("screenshot.png");13            await browser.CloseAsync();14        }15    }16}

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