Html2Pdf.Lib 0.1.0

Html 2 Pdf

The best tool to convert HTML to PDF in .NET

Html2Pdf.Lib is an Open Source library with an MIT license that converts an HTML file into a PDF file.

This library was built using wkhtmltopdf, which is a command-line tool for converting HTML files to PDFs using the QT Webkit rendering engine.

No secret: The C# code simply calls the wkhtmltopdf executable and passes the necessary parameters. It's that simple: wkhtmltopdf -q --margin-bottom 10 --margin-left 10 --margin-right 10 --margin-top 10 -s A4

There are many other parameters to configure the conversion, such as page size, margins, orientation, image quality, etc.

However, it is important to note that wkhtmltopdf was discontinued in 2020, with its repository archived in 2023 and no longer supported. But it is still a widely used tool that works very well.

What's new in V0.1.0

• Added new Argument configuration : AddLogger
  • All error messages can be automatically written to the log provider.
• Added new Argument configuration : TimeoutConvert
  • Conversion now has a default limit of 30 seconds and a minimum of 500 milliseconds. This is valid for any possible execution failure or infinite loop/deadlock.
• Added target frameworks: .NET9, .NET8, .NETSTANDARD2.1.
• Added new methods for direct conversion to PDF file (faster. No need to create, read to bytes and delete):
  • FromHtml(string filename, string html, Arguments? arguments = null)
  • FromUrl(string filename, Uri url, Arguments? arguments = null)
  • FromRazorTemplate<T>(string filename, string razorTemplate, T model, Arguments? arguments = null)
• Changed return type convert from bytes[] to new class ConvertResult:
  • Property Content = PDF in bytes[].
  • Property HasValue property = boolean if conversion is successful.
  • Property FileName = Name of the PDF file created when the filename parameter is used. the Content property is null in this case.
  • Property Error = The exception generated when an error occurs during conversion.
  • Property Elapsedtime = Elapsed time to perform the conversion.

How to Install

dotnet add package Html2Pdf.Lib

How to Use

First, we need to define the conversion parameters. For this, we use the Arguments class.

These parameters are optional and can be configured as needed.

Basically, they are the same parameters that wkhtmltopdf accepts. If you want to know more, check out the documentation.

using Html2Pdf.Lib;

//log provider for console app
ILoggerFactory factory = LoggerFactory.Create(builder =>
{
    builder.AddConsole();
    builder.SetMinimumLevel(LogLevel.Debug);
});
ILogger logger = factory.CreateLogger("Program");

var arguments = new Arguments()
    // When jpeg compressing images use this quality (default 94)
    .SetImageQuality(80)

    // Do not print background
    .DoNotPrintBackground()

    // Do not load or print images
    .DoNotLoadOrPrintImages()

    // Do not use lossless compression on pdf objects
    .WithNoPdfCompression()

    // Do not make links to remote web pages
    .DisableExternalLinks()

    // Do not make local links
    .DisableInternalLinks()

    // The title of the generated pdf file (The title of the first document is used if not specified)
    .SetTitle("This is a sample PDF document")

    // Indicates whether the PDF should be generated in lower quality.
    .WithLowQuality()

    // Number of copies to print into the PDF file.
    .SetCopies(2)

    // Indicates whether the PDF should be generated in grayscale.
    .WithGrayScale()

    // Replace [name] with value in header and footer (repeatable)
    .Replace("HTML to PDF Test Page", "HTML to PDF Test Page - Sample 1")

    // Set the starting page number (default 0)
    .SetOffPageOffset(2)

    // Sets the page margins
    .SetPageMargins(10, 10, 10, 10)

    // Sets the page Width. Has priority over "SetPageSize" but "SetPageHeight" has to be also specified.
    .SetPageWidth(210)

    // Sets the page Height. Has priority over "SetPageSize" but "SetPageWidth" has to be also specified.
    .SetPageHeight(297)

    // Set the page Orientation
    .SetPageOrientation(PageOrientation.Landscape)

    // The default page size of the rendered document is A4.
    .SetPageSize(PageSize.A4)

    // Disable SmartSets the page size.
    .DisableSmartShrinking()

    // Turn HTML form fields into pdf form fields
    .EnableForms()

    // Display line below the header
    .DisplayHeaderLine()

    // Set header text
    .SetHeaderText("Header Text Sample 1", TextAlignment.Center, "Verdana", 15)

    // Spacing between footer and content in mm (default 0)
    .SetHeaderSpacing(23)

    // Display line above the footer
    .DisplayFooterLine()

    // Set footer text
    .SetFooterText("Footer Text Sample 1", TextAlignment.Center, "Verdana", 15)

    // Spacing between footer and content in mm (default 0)
    .SetFooterSpacing(23);

    //add current ILogger
    .AddLogger(logger)

    //set timeout convert to PDF
    .TimeoutConvert(10000);

It is possible to generate a PDF in four ways:

From an HTML Text

var html = 
"""
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>HTML Simples</title>
    <style>
        body {
            font-family: Arial, sans-serif;
            background-color: #f4f4f9;
            margin: 0;
            padding: 20px;
        }
        header {
            background: #007BFF;
            color: white;
            padding: 10px 0;
            text-align: center;
        }
        main {
            margin-top: 20px;
            text-align: center;
        }
        footer {
            margin-top: 20px;
            text-align: center;
            color: #555;
        }
    </style>
</head>
<body>
    <header>
        <h1>Hello World!</h1>
    </header>
    <main>
        <p>This is a Sample! Convert HTML to PDF</p>
    </main>
    <footer>
        <p>&copy; 2024 My Sample HTML</p>
    </footer>
</body>
</html>
""";

var resultConvert = Converter.FromHtml(html, arguments);
var elapsedtimeConvert = resultConvert.Elapsedtime;
if (resultHtml.HasValue)
{
   var bytespdf = resultConvert.Content!
}
else
{
   //Erro See resultConvert.Error
}

From Url

var url = new Uri("https://en.wikipedia.org/wiki/C_Sharp_(programming_language)");
var resultConvert = Converter.FromUrl(url), arguments);
var elapsedtimeConvert = resultConvert.Elapsedtime;
if (resultHtml.HasValue)
{
   var bytespdf = resultConvert.Content!
}
else
{
   //Erro See resultConvert.Error
}

From an HTML template using Razor Syntax

public record Product(string Name, decimal Price);
public record Order(string CustomerName, string CustomerAddress, string CustomerPhoneNumber, List<Product> Products);

var razorTemplate =
"""
<!DOCTYPE html>
<html lang="pt-br">
<head>
    <meta charset="UTF-8">
    <title>Customer Details</title>
    <style>
        table {
            border-collapse: collapse;
            width: 100%;
        }
        th, td {
            border: 1px solid #ddd;
            padding: 8px;
        }
        th {
            background-color: #f4f4f4;
            text-align: left;
        }
    </style>
</head>
<body>
    <h1>Customer Details</h1>
    <p><strong>Name:</strong> @Model.CustomerName</p>
    <p><strong>Address:</strong> @Model.CustomerAddress</p>
    <p><strong>Phone Number:</strong> @Model.CustomerPhoneNumber</p>

    <h2>Products (@Model.Products.Count)</h2>
    @if(Model.Products.Any())
    {
        <table>
            <thead>
                <tr>
                    <th>Product Name</th>
                    <th>Price</th>
                </tr>
            </thead>
            <tbody>
                @foreach (var product in Model.Products)
                {
                    <tr>
                        <td>@product.Name</td>
                        <td>@product.Price.ToString("C")</td>
                    </tr>
                }
            </tbody>
        </table>
    } 
    else
    {
        <p>No products found.</p>
    }
</body>
</html>
""";

var order = new Order("Roberto Rivellino", "Rua São Jorge, 777", "+55 11 912345678", [
    new("Product 1", 9.99m),
    new("Product 2", 19.99m),
    new("Product 3", 29.99m)
]);
var resultConvert = Converter.FromRazorTemplate(razorTemplate, order, arguments);
var elapsedtimeConvert = resultConvert.Elapsedtime;
if (resultHtml.HasValue)
{
   var bytespdf = resultConvert.Content!
}
else
{
   //Erro See resultConvert.Error
}

From an HTML template using Razor Syntax in Batch

var order1 = new Order("Roberto Rivellino", "Rua São Jorge, 777", "+55 11 912345678", [
    new("Product 1", 9.99m),
    new("Product 2", 19.99m),
    new("Product 3", 29.99m)
]);
var byteArrayRazorTemplate = Converter.FromRazorTemplate(razorTemplate, order1, arguments);

var order2 = new Order("Sócrates", "Rua das Alamedas, 888", "+55 11 912345678", [
    new("Product 1", 2.99m),
    new("Product 2", 4.99m),
    new("Product 3", 6.99m)
]);

var order3 = new Order("Biro Biro", "Avenida das Orquídeas, 999", "+55 11 912345678", [
    new("Product 1", 3.99m),
    new("Product 2", 5.99m),
]);

var order4 = new Order("Casagrande", "Estrada das Flores, 456", "+55 11 912345678", [ ]);

var resultConvertRazorTemplateList = Converter.FromRazorTemplateBatch(razorTemplate, [ order1, order2, order3, order4 ], arguments);
for (int i = 0; i < resultConvertRazorTemplateList.Count; i++)
{
    var resultConvert = resultConvertRazorTemplateList.ElementAt(i);
    var elapsedtimeConvert = resultConvert.Elapsedtime;
    if (resultHtml.HasValue)
    {
        var bytespdf = resultConvert.Content!
    }
    else
    {
        //Erro See resultConvert.Error
    }
    ...
}