Convert HTML to PDF from raw HTML in C# with HTTPWebRequest

In this guide, we'll show you how to convert raw HTML to PDF using C# and the HTTPWebRequest library.

Converting raw HTML content to PDF is useful when you have HTML content that isn't hosted on a web server.

using System;
using System.Net;
using System.Text;
using System.IO;
using System.Threading.Tasks;

// You can get an API key at https://pdfshift.io
var apiKey = "sk_xxxxxxxxxxxx";

var request = (HttpWebRequest)WebRequest.Create("https://api.pdfshift.io/v3/convert/pdf");
request.Method = "POST";
request.ContentType = "application/json";
request.Headers.Add("X-API-Key", apiKey);

var payload = new
{
    source = "<html><body><h1>Hello World</h1></body></html>"
};

var json = System.Text.Json.JsonSerializer.Serialize(payload);
byte[] data = Encoding.UTF8.GetBytes(json);
request.ContentLength = data.Length;

using (var stream = request.GetRequestStream())
{
    stream.Write(data, 0, data.Length);
}

try
{
    var response = (HttpWebResponse)request.GetResponse();
    
    // Handle errors:
    if (response.StatusCode >= HttpStatusCode.BadRequest)
    {
        throw new Exception($"Request failed with status code {response.StatusCode}");
    }

    using (var reader = new StreamReader(response.GetResponseStream()))
    {
        var result = reader.ReadToEnd();
        File.WriteAllText("result.pdf", result);
    }

    Console.WriteLine("The PDF document was generated and saved to result.pdf");
}
catch (WebException ex)
{
    Console.WriteLine($"Error: {ex.Message}");
}

This allows you to convert HTML content directly to PDF without needing a URL.

For further details on the source property and its usage, please refer to our dedicated documentation.

We hope this guide was helpful. If you have any questions or noticed any issues on the code above,
feel free to drop us a line.