As of my last knowledge update in September 2021, Microsoft Edge did not provide a direct API for programmatically printing PDF files from a C# application. However, you could use a workaround by launching Microsoft Edge with the PDF file's URL and then letting the user interact with the browser to print the PDF manually. Here's how you can do it:

using System.Diagnostics;

public void PrintPDFViaEdge(string pdfUrl)
{
    try
    {
        // Create a ProcessStartInfo with the URL to the PDF file
        ProcessStartInfo psi = new ProcessStartInfo
        {
            FileName = "msedge.exe", // Use the path to msedge.exe if not in system PATH
            Arguments = pdfUrl
        };

        // Start Microsoft Edge with the PDF URL
        Process.Start(psi);
    }
    catch (Exception ex)
    {
        // Handle any exceptions (e.g., if Microsoft Edge is not installed)
        Console.WriteLine("Error: " + ex.Message);
    }
}

In this code:

• ProcessStartInfo is used to specify the application to be launched (Microsoft Edge) and the URL of the PDF file you want to open for printing.
• Process.Start(psi) is used to start Microsoft Edge with the specified URL.

Please note that this approach relies on the user manually interacting with Microsoft Edge to print the PDF. There is no direct programmatic way to trigger printing from C# code using Microsoft Edge's API.

Additionally, the availability and behavior of this method might change with updates to Microsoft Edge. Always check the latest documentation and APIs provided by Microsoft if you need more advanced control over printing PDFs from your C# application.