What is ChromeHtmlToPdf?

ChromeHtmlToPdf is a 100% managed C# .NETStandard 2.0 library and .NET Core 3.1 console application (that also works on Linux and macOS) that can be used to convert HTML to PDF format with the use of Google Chrome

Why did I make this?

I needed a replacement for wkHtmlToPdf, a great tool but the activity on this project is low and it's not 100% compatible with HTML5.

License Information

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NON INFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.

Installing via NuGet

The easiest way to install ChromeHtmlToPdf is via NuGet.

In Visual Studio's Package Manager Console, simply enter the following command:

Install-Package ChromeHtmlToPdf

Converting a file or url from code

using (var converter = new Converter())
{
    converter.ConvertToPdf(new Uri("http://www.google.nl"), @"c:\google.pdf");
}

// Show the PDF
System.Diagnostics.Process.Start(@"c:\google.pdf");

Converting from Internet Information Services (IIS)

Download Chrome portable and extract it
Let your website run under the ApplicationPool identity
Copy the files to the same location as where your project exists on the webserver
Reference the ChromeHtmlToPdfLib.dll from your webproject
Call the converter.ConverToPdf method from code

Thats it.

If you get strange errors when starting Chrome than this is due to the account that is used to run your site. I had a simular problem and solved it by hosting ChromeHtmlToPdf in a Windows service and making calls to it with a WCF service.

Converting from the command line

ChromeHtmlToPdf.exe --input https://www.google.com --output c:\google.pdf

Console app exit codes

0 = successful, 1 = an error occurred

Installing on Linux or macOS

Installing .NET

See this url about how to install .NET on Linux

https://docs.microsoft.com/en-us/dotnet/core/install/linux

And this url about how to install .NET on macOS

https://docs.microsoft.com/en-us/dotnet/core/install/macos

Installing Chrome

See this url about how to install Chrome on Linux

https://support.google.com/chrome/a/answer/9025903?hl=en

And this url about how to install Chrome on macOS

https://support.google.com/chrome/a/answer/7550274?hl=en

Pre compiled binaries

You can find pre compiled binaries for Windows, Linux and macOS over here

https://github.com/Sicos1977/ChromeHtmlToPdf/releases/download/2.0.11/ChromeHtmlToPdf_211.zip https://github.com/Sicos1977/ChromeHtmlToPdf/releases/download/2.1.6/ChromeHtmlToPdf_216.zip https://github.com/Sicos1977/ChromeHtmlToPdf/releases/download/2.2/ChromeHtmlToPdf_220.zip https://github.com/Sicos1977/ChromeHtmlToPdf/releases/download/2.5.1/ChromeHtmlToPdf_251.zip

Logging

From version 2.5.0 ChromeHtmlToPdfLib uses the Microsoft ILogger interface (https://docs.microsoft.com/en-us/dotnet/api/microsoft.extensions.logging.ilogger?view=dotnet-plat-ext-5.0). You can use any logging library that uses this interface.

ChromeHtmlToPdfLib has some build in loggers that can be found in the ChromeHtmlToPdfLib.Logger namespace.

For example

var logger = !string.IsNullOrWhiteSpace(<some logfile>)
                ? new ChromeHtmlToPdfLib.Loggers.Stream(File.OpenWrite(<some logfile>))
                : new ChromeHtmlToPdfLib.Loggers.Console();

Setting a common Chrome cache directory

You can not share a cache directory between Chrome instances because the first instance that is using the cache directory will lock it for its own use. The most efficient way to make optimal use of a cache directory is to create one for each instance that you are running.

I'm using Chrome from a WCF service and used the class below to make optimal use of cache directories. The class will create an instance id that I use to create a cache directory for each running Chrome instance. When the instance shuts down the instance id is put back in a stack so that the next executing instance can use this directory again.

public static class InstanceId
{
    #region Fields
    private static readonly ConcurrentStack<string> ConcurrentStack;
    #endregion

    #region Constructor
    static InstanceId()
    {
        ConcurrentStack = new ConcurrentStack<string>();

        for(var i = 100000; i > 0; i--)
            ConcurrentStack.Push(i.ToString().PadLeft(6, '0'));
    }
    #endregion

    #region Pop
    /// <summary>
    /// Returns an instance id and pops it from the <see cref="ConcurrentStack"/>
    /// </summary>
    /// <returns></returns>
    public static string Pop()
    {
        if (ConcurrentStack.TryPop(out var instanceId))
            return instanceId;

        throw new Exception("Instance id stack is empty");
    }
    #endregion

    #region Push
    /// <summary>
    /// Pushes the <paramref name="instanceId"/> back on top of the <see cref="ConcurrentStack"/>
    /// </summary>
    /// <param name="instanceId"></param>
    public static void Push(string instanceId)
    {
        ConcurrentStack.Push(instanceId);
    }
    #endregion
}

Core Team

Sicos1977 (Kees van Spelde)

Support

If you like my work then please consider a donation as a thank you.

Reporting Bugs

Have a bug or a feature request? Please open a new issue.

Before opening a new issue, please search for existing issues to avoid submitting duplicates.

vincentwh2018/ChromeHtmlToPdf