How can I convert a PDF file to an image format (JPG, PNG, etc.), using C# and Windows Forms?

// open and load the file
using (FileStream fs = new FileStream(@"Documents\TestFile.pdf", FileMode.Open))
{
// this object represents a PDF document
Document document = new Document(fs);

// default rendering settings
RenderingSettings settings = new RenderingSettings();

// process and save pages one by one
for (int i = 0; i < document.Pages.Count; i++)
{
Page currentPage = document.Pages[i];

// we use original page's width and height for image as well as default rendering settings
using (Bitmap bitmap = currentPage.Render((int)currentPage.Width, (int)currentPage.Height,settings))
{
bitmap.Save(string.Format("{0}.png", i), ImageFormat.Png);
}
}
// preview first rendered page
Process.Start("0.png");
}