I solved my problem

It seems that the .net does not support this, I had to use the COM API

Horrible code but it works, so far there is no other way

This is the code, if anybody need to use it


using Interop.PeachwServer;

private Dictionary<string, double> ImportTaxes()
{
var taxCodes = new Dictionary<string, double>();
Interop.PeachwServer.Login login = new Interop.PeachwServer.Login();
Interop.PeachwServer.Application app;
app = (Interop.PeachwServer.Application)login.GetApplication("Peachtree Software", "9E5643PCU118X6C");

var file = System.IO.Path.GetTempFileName();
var exporter = (Export)app.CreateExporter(PeachwIEObj.peachwIEObjSalesTaxCodes);
exporter.AddToExportFieldList((short)PeachwIEObjSalesTaxCodesField.peachwIEObjSalesTaxCodesField_SalesTaxCodeId);
exporter.AddToExportFieldList((short)PeachwIEObjSalesTaxCodesField.peachwIEObjSalesTaxCodesField_TaxRate);
exporter.SetFilename(file);
exporter.SetFileType(PeachwIEFileType.peachwIEFileTypeCSV);
try
{
exporter.Export();
}
catch (Exception ee)
{
Logger.Log(ee);
}

using (var reader = new StreamReader(file))
{
string line;
while ((line = reader.ReadLine()) != null)
{
var parts = line.Split(new char[] { ',' });
if (parts.Length == 2)
if (!taxCodes.ContainsKey(parts[0]))
taxCodes.Add(parts[0], Convert.ToDouble(parts[1]));
}
}
return taxCodes;
}

If possible, I share my result and that it is working for me.

public IEnumerable<Taxes> Get()
{
BindingFlags bf = BindingFlags.Instance | BindingFlags.NonPublic;

List<Taxes> taxes = new List<Taxes>();
Company company = Connection.company;

SalesTaxCodeList salesTaxs = company.Factories.SalesTaxCodeFactory.List();
salesTaxs.Load();

foreach (SalesTaxCode salesTax in salesTaxs)
{
Taxes tax = new Taxes();
decimal taxPerAgency = 0;

SalesTaxAgencyCollection salesTaxsAgencies = salesTax.SalesTaxAgencies;
foreach (SalesTaxAgency salesTaxagency in salesTaxsAgencies)
{
Type t = salesTaxagency.GetType();
var salesDomainTax = (Sage.Peachtree.Domain.Entities.SalesTaxAgency)t.GetProperty("MyDomainEntity", bf).GetValue(salesTaxagency);
Sage.Peachtree.Domain.Entities.FixedRateSalesTaxRateCalculation rateCalculation = (Sage.Peachtree.Domain.Entities.FixedRateSalesTaxRateCalculation)salesDomainTax.RateCalculation;
taxPerAgency = taxPerAgency + rateCalculation.Rate;
}

tax.ID = salesTax.ID.ToString();
tax.Description = salesTax.Description.ToString();
tax.Key = salesTax.Key.Guid.ToString();
tax.Rate = taxPerAgency;

taxes.Add(tax);
}

return taxes;
}