Printing zpl and pdf documents through C#

Hi Friends,

 We have seen ways to print a pdf through C# but printing zpl on zebra printers doesn't seems to work like pdf but here I'm demonstrating a way which can print zpl (*.zpl, on zebra printers) and pdf (*.pdf) or other documents types. This also could be a best option as it doesn't depend on any other third party libraries (open source or paid).

public class BasePrintUtility
    {
        private static bool SendRawBytesToPrinter(string szPrinterName, string printerFileName, IntPtr pBytes, Int32 dwCount)
        {
            Int32 dwError = 0, dwWritten = 0;
            IntPtr hPrinter = new IntPtr(0);
            DOCINFOA di = new DOCINFOA();
            bool bSuccess = false; // Assume failure unless you specifically succeed.

            di.pDocName = printerFileName;
            di.pDataType = "RAW";

            // Open the printer.
            if (OpenPrinter(szPrinterName.Normalize(), out hPrinter, IntPtr.Zero))
            {
                // Start a document.
                if (StartDocPrinter(hPrinter, 1, di))
                {
                    // Start a page.
                    if (StartPagePrinter(hPrinter))
                    {
                        // Write your bytes.
                        bSuccess = WritePrinter(hPrinter, pBytes, dwCount, out dwWritten);
                        EndPagePrinter(hPrinter);
                    }
                    EndDocPrinter(hPrinter);
                }
                ClosePrinter(hPrinter);
            }
            // If you did not succeed, GetLastError may give more information
            // about why not.
            if (bSuccess == false)
            {
                dwError = Marshal.GetLastWin32Error();
            }
            return bSuccess;
        }
             
        // Structure and API declarions:
        [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
        public class DOCINFOA
        {
            [MarshalAs(UnmanagedType.LPStr)]
            public string pDocName;
            [MarshalAs(UnmanagedType.LPStr)]
            public string pOutputFile;
            [MarshalAs(UnmanagedType.LPStr)]
            public string pDataType;
        }
        [DllImport("winspool.Drv", EntryPoint = "OpenPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool OpenPrinter([MarshalAs(UnmanagedType.LPStr)] string szPrinter, out IntPtr hPrinter, IntPtr pd);

        [DllImport("winspool.Drv", EntryPoint = "ClosePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool ClosePrinter(IntPtr hPrinter);

        [DllImport("winspool.Drv", EntryPoint = "StartDocPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool StartDocPrinter(IntPtr hPrinter, Int32 level, [In, MarshalAs(UnmanagedType.LPStruct)] DOCINFOA di);

        [DllImport("winspool.Drv", EntryPoint = "EndDocPrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool EndDocPrinter(IntPtr hPrinter);

        [DllImport("winspool.Drv", EntryPoint = "StartPagePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool StartPagePrinter(IntPtr hPrinter);

        [DllImport("winspool.Drv", EntryPoint = "EndPagePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool EndPagePrinter(IntPtr hPrinter);

        [DllImport("winspool.Drv", EntryPoint = "WritePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
        public static extern bool WritePrinter(IntPtr hPrinter, IntPtr pBytes, Int32 dwCount, out Int32 dwWritten);

        public bool SendDocumentToPrinter(string filePath, PrintSettings printSettings)
        {
            // Open the file.
            FileInfo fileInfo = new FileInfo(filePath);
            Byte[] bytes = null;
            bool bSuccess = false;
            // Your unmanaged pointer.
            IntPtr pUnmanagedBytes = new IntPtr(0);
            int nLength;
            using (FileStream fs = fileInfo.OpenRead())
            {
                //FileStream fs = new FileStream(szFileName, FileMode.Open);
                // Create a BinaryReader on the file.
                BinaryReader br = new BinaryReader(fs);
                // Dim an array of bytes big enough to hold the file's contents.
                bytes = new Byte[fs.Length];
                nLength = Convert.ToInt32(fs.Length);
                // Read the contents of the file into the array.
                bytes = br.ReadBytes(nLength);
            }
            // Allocate some unmanaged memory for those bytes.
            pUnmanagedBytes = Marshal.AllocCoTaskMem(nLength);
            // Copy the managed byte array into the unmanaged array.
            Marshal.Copy(bytes, 0, pUnmanagedBytes, nLength);
            // Send the unmanaged bytes to the printer.
            for (int i = 0; i < printSettings.Copies; i++)
            {
                bSuccess = SendRawBytesToPrinter(printSettings.PrinterName, fileInfo.Name, pUnmanagedBytes, nLength);
            }
            // Free the unmanaged memory that you allocated earlier.
            Marshal.FreeCoTaskMem(pUnmanagedBytes);
            return bSuccess;
        }

        public bool SendDocumentToPrinter(byte[] content, int copies, string printerName, string fileName)
        {
            bool status = false;
            IntPtr pUnmanagedBytes;
            int nLength = content.Length;
            // Allocate some unmanaged memory for those bytes.
            pUnmanagedBytes = Marshal.AllocCoTaskMem(nLength);
            // Copy the managed byte array into the unmanaged array.
            Marshal.Copy(content, 0, pUnmanagedBytes, nLength);
            // Send the unmanaged bytes to the printer.
            for (int i = 0; i < copies; i++)
            {
               status = SendRawBytesToPrinter(printerName, fileName, pUnmanagedBytes, nLength);
            }
            // Free the unmanaged memory that you allocated earlier.
            Marshal.FreeCoTaskMem(pUnmanagedBytes);
            return status;
        }
    }

isn't it simple.

Note: This is not optimized code and just  a sample. You must optimize it as your need before using it.

Source: https://github.com/andyyou/SendToPrinter/blob/master/Printer/RawPrinterHelper.cs


Thanks.