Printing file through printer VB.Net or C# code

using System.Diagnostics.Process;





Process process = new Process();

process.StartInfo.FileName = pdf Path;
process.UseShellExecute = true;
process.StartInfo.Verb = "printto";
process.StartInfo.Arguments = "\"" + printerName + "\"";
process.Start();

process.WaitForInputIdle();
process.Kill();

these might help you 
http://www.c-sharpcorner.com/Blogs/13946/
http://www.codeproject.com/Tips/598424/How-to-Silently-Print-PDFs-using-Adobe-Reader-and