System.Exception: 'Error getting printers in DymoSDK

Question

Hi members, I have an error while trying to print labels on a Dymo Labelwriter. The class works standalone in a simple form program but in a bigger program it fails. The error detail is: EntryPointNotFoundException: Cannot find entrypoint SpoolMon_AddListener in DLL PrintingSupportLibrary.dll. This exception was originally thrown at this call stack: DYMO.LabelAPI.Windows.Printers.SpoolerMonitorGateway.SpoolerMonitorGateway() in SpoolerMonitorGateway.cs DYMO.LabelAPI.Windows.PrinterDiscovery.WindowsDeviceDiscoveryAgent.CreateNewSpoolerMonitorGateway() in WindowsDeviceDiscoveryAgent.cs Ther class where this exception is:

using DymoSDK.Implementations;
using DymoSDK.Interfaces;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace VoorraadBeheer.Classes
{
    class DymoPrinters
    {
        public List<IPrinter> DymoPrinterList;

        private IDymoPrinter tmpIDymoPrinter;
        private IDymoLabel tmpIDymoLabel;
        public void Initialize()
        {
            DymoSDK.App.Init();
            tmpIDymoPrinter = DymoPrinter.Instance;
            tmpIDymoLabel = DymoLabel.Instance;
            DymoPrinterList = tmpIDymoPrinter.GetPrinters().Result.ToList();<ERROR         }

        public string LoadLabelXml(string LabelPath)
        {
            tmpIDymoLabel.LoadLabelFromFilePath(LabelPath);
            return tmpIDymoLabel.XMLContent;
        }

        public IDymoLabel MakeLabelFromXml(string LabelXml)
        {
            tmpIDymoLabel.LoadLabelFromXML(LabelXml);
            return tmpIDymoLabel;
        }
        public bool PrintLabel(IDymoLabel label, string PrinterName, int amount = 1)
        {
            return tmpIDymoPrinter.PrintLabel(label, PrinterName, amount).Result;
        }


    }
}

Answer 1

The correct class that works:

            {

using DymoSDK.Implementations;
using DymoSDK.Interfaces;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace VoorraadBeheer.Classes
{
    public class DymoPrinters
    {
        public List<IPrinter> DymoPrinterList;
        public List<IPrinter> FullDymoPrinterList;
        private IDymoPrinter tmpIDymoPrinter;
        private IDymoLabel tmpIDymoLabel;
        public void Initialize()
        {
            //ref PresentationFramework + WindowsBase
            if (null == System.Windows.Application.Current)
            {
                new System.Windows.Application();
            }
            DymoSDK.App.Init();
            tmpIDymoPrinter = DymoPrinter.Instance;
            tmpIDymoLabel = DymoLabel.Instance;
            FullDymoPrinterList = tmpIDymoPrinter.GetPrinters().Result.ToList();
            DymoPrinterList = new List<IPrinter>();
            foreach (IPrinter printer in FullDymoPrinterList)
            {
                if (printer.IsConnected)
                {
                    DymoPrinterList.Add(printer);
                }
            }
        }
        public string LoadLabelXml(string LabelPath)
        {
            tmpIDymoLabel.LoadLabelFromFilePath(LabelPath); // labelname and path
            return tmpIDymoLabel.XMLContent;
        }
        public IDymoLabel MakeLabelFromXml(string LabelXml)
        {
            tmpIDymoLabel.LoadLabelFromXML(LabelXml);
            return tmpIDymoLabel;
        }
        public bool PrintLabel(IDymoLabel label, string PrinterName, int amount = 1)
        {
            return tmpIDymoPrinter.PrintLabel(label, PrinterName, amount).Result;
        }
        public async Task <int> GetRemainingLabels(string PrinterName)
        {
            rollstatus = string.Empty;
            labelsremaining = 0;
            labelname = string.Empty;
            var tmpi = await DymoPrinter.Instance.GetRollStatusInPrinter(PrinterName);
            if (tmpi != null)
            {
                rollstatus = tmpi.RollStatus.ToString();
                labelsremaining = Convert.ToInt32(tmpi.LabelsRemaining);
                labelname = tmpi.Name;
                return labelsremaining;
            }
            return -1;
        }
            
            
            
        
    public string rollstatus { get; set; }
    public int labelsremaining { get; set; }
    public string labelname { get; set; }
    }
}

Answer 2

For I forget, the init if the class and members. Ask me if you don't get it at work

   public partial class DymoBarcodePrinter : Form
   {
 DymoPrinters myDymoPrinters;
 
 IDymoLabel tmpLabel;
       private void DymoBarcodePrinter_Load(object sender, EventArgs e)
       {
           myDymoPrinters = new DymoPrinters();
           myDymoPrinters.Initialize();
           foreach (IPrinter item in myDymoPrinters.DymoPrinterList)
           {
               LabelWriterCmb.Items.Add(item.Name);
           }
           if (LabelWriterCmb.Items.Count > 0)
           {
               LabelWriterCmb.SelectedIndex = 0;
           }
           else
           {
               MessageBox.Show("Geen Dymo labelwriter gevonden");
               Close();
               return;
           }
}
       private async void PrintLabelBtn_Click1(object sender, EventArgs e, ComboBox 						    labelWriterCmb)
       {
                string tmpLabelXML = myDymoPrinters.LoadLabelXml(Path.Combine(Environment.GetFolderPath(
                                            Environment.SpecialFolder.LocalApplicationData), "LoginPC\\Voorraadbeheer\\product.label"));
string  tmpLabel = myDymoPrinters.MakeLabelFromXml(xmlstring);
                var tmp1  = await myDymoPrinters.GetRemainingLabels(labelWriterCmb.Text);
  if (tmp1 != null)
  {
      remaining.Text = tmp1.ToString();
  
  
      myDymoPrinters.PrintLabel(tmpLabel, labelWriterCmb.Text, aantal);
      var tmpi = await DymoPrinter.Instance.GetRollStatusInPrinter(labelWriterCmb.Text);
      rollstatus = string.Empty;
      labelsremaining = 0;
      labelname = string.Empty    ;
      if (tmpi != null)
      {
          rollstatus = tmpi.RollStatus.ToString();
          labelsremaining = Convert.ToInt32(tmpi.LabelsRemaining);
          labelname = tmpi.Name;
          
          if (labelsremaining < 6)
          {
              remaining.ForeColor = Color.Red;
          }
          Labelstatus.Text = rollstatus;
          LabelNaam.Text = labelname;
          remaining.Text = labelsremaining.ToString();
      }
  }