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Data from List<Memo> doesn't show in datagridview

I have a list made by user input which is bound to a datasource class, I also have a datagridview where the data is supposed to be put into the datagrid.
private void ViewMemo_Load(object sender, EventArgs e)
{
dgvMemo.DataSource = Datasources.memorecorders;
}
this is the AddMemo class
private void btAdd_Click(object sender, EventArgs e)
{
int SerialId;
SerialId = int.Parse(txtSerialId.Text);
decimal price;
price = decimal.Parse(txtPrijs.Text);
MemoRecorder m1 = new MemoRecorder(SerialId);
m1.make = txtMerk.Text;
m1.model = txtModel.Text;
m1.priceExBtw = price;
m1.creationDate = dtProductie.Value;
foreach (MemoCartridgeType mem in Enum.GetValues(typeof(MemoCartridgeType)))
{
if (cbCartridge.SelectedValue.ToString() == mem.ToString())
{
m1.maxCartridgeType = mem;
}
}
Datasources.memorecorders.Add(m1);
MessageBox.Show("uitkomst: Merk: " + m1.make + "model: " + m1.model + " ,prijs Ex btw: "+ m1.priceExBtw + " ,CartridgeType: "+ m1.maxCartridgeType
+ " ,Creatie Datum: " + m1.creationDate);
txtMerk.Text = String.Empty;
txtModel.Text = String.Empty;
txtPrijs.Text = String.Empty;
}
but when I view the datagridview the data is not in there, what did I do wrong?

Datasources.memorecorders.Add(m1);
dgvMemo.DataSource = Datasources.memorecorders;
MessageBox.Show("uitkomst: Merk: " + m1.make + "model: " + m1.model + " ,prijs Ex btw: "+ m1.priceExBtw + " ,CartridgeType: "+ m1.maxCartridgeType
+ " ,Creatie Datum: " + m1.creationDate);

The process cannot access the file "XXX.txt" because it is being used by another process

I would like to write to and read from the same text file. However, I faced the issue of "The process cannot access "XXX.txt" because it is being used by another process".
I created two classes, A & B and define two objects for each of the classes in the main form.
Class A will be writing data into the text file while Class B will reading data from the text file at the same time.
I had put Class B in a timer while Class A will start when I click a button.
Class A :-
private void Processdata(string indata)
{
//======================================[TCP/IP]=====================================================//
using (StreamWriter sw = new StreamWriter(TCPfilename, true))
{
var time = DateTime.Now;
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
sw.WriteLine(formattedTime + "\t" + indata);
}
// Regular Expression for WIFI Drone & Phantom 3 Drone
Regex regexp3_1 = new Regex(#"^AH(60601F740D70)(-\d{0,2})");
Regex regexp3_2 = new Regex(#"^AH(60601F415CAF)(-\d{0,2})");
Regex regexp3_3 = new Regex(#"^AH(60601F078D3E)(-\d{0,2})");
Regex regexp3 = new Regex(#"^AH(60601F(\S{0,6}))(-\d{0,2})");
Regex regexP3 = new Regex(#"^GGP3(\S{0,8})");
Regex regexPA = new Regex(#"^AH(A0143D\S{0,6})(-\d{0,2})");
Regex regex3D = new Regex(#"^AH(8ADC96\S{0,6})(-\d{0,2})");
Regex regexMA = new Regex(#"^AH(60601F93F3FB)(-\d{0,2})");
Regex regexMP = new Regex(#"^AH(60601F33729E)(-\d{0,2})");
Regex regexTL = new Regex(#"^AH(60601FD8A1EF)(-\d{0,2})");
// Regular Expression for WIFI
Regex regexAH = new Regex(#"^AH(\S{0,12})(-\d{0,2})");
Regex regexAH2 = new Regex(#"^AH(\S{0,12})(-\d{0,2})\S{0,6}(\S{0,74})");
// Match WIFI Drone & Phantom 3 Drone Data with Regular Expression
Match matchp3_1 = regexp3_1.Match(indata);
Match matchp3_2 = regexp3_2.Match(indata);
Match matchp3_3 = regexp3_3.Match(indata);
Match matchp3 = regexp3.Match(indata);
Match matchP3 = regexP3.Match(indata);
Match matchPA = regexPA.Match(indata);
Match match3D = regex3D.Match(indata);
Match matchMA = regexMA.Match(indata);
Match matchMP = regexMP.Match(indata);
Match matchTL = regexTL.Match(indata);
// Match WIFI Data with Regular Expression
Match matchAH = regexAH.Match(indata);
Match matchAH2 = regexAH2.Match(indata);
using (StreamWriter rssi = new StreamWriter(TCPRSSIfilename, true))
{
var time = DateTime.Now;
// Parrot
if (matchPA.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-Parrot" + "; " + matchPA.Groups[1].Value.ToString() + "; " + matchPA.Groups[0].Value.ToString() + "; " + matchPA.Groups[2].Value.ToString());
rssi.Flush();
}
// 3DR
else if (match3D.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-3DR_Solo" + "; " + match3D.Groups[1].Value.ToString() + "; " + match3D.Groups[0].Value.ToString() + "; " + match3D.Groups[2].Value.ToString());
rssi.Flush();
}
// Mavic Air
else if (matchMA.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-Mavic_Air" + "; " + matchMA.Groups[1].Value.ToString() + "; " + matchMA.Groups[0].Value.ToString() + "; " + matchMA.Groups[2].Value.ToString());
rssi.Flush();
}
// Mavic Pro
else if (matchMP.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-Mavic_Pro" + "; " + matchMP.Groups[1].Value.ToString() + "; " + matchMP.Groups[0].Value.ToString() + "; " + matchMP.Groups[2].Value.ToString());
rssi.Flush();
}
// Tello
else if (matchTL.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-Tello" + "; " + matchTL.Groups[1].Value.ToString() + "; " + matchTL.Groups[0].Value.ToString() + "; " + matchTL.Groups[2].Value.ToString());
rssi.Flush();
}
// Specific Phantom 3 (MAC : 740D70)
else if (matchp3_1.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-DJI_Phantom_3_STD" + "; " + matchp3_1.Groups[1].Value.ToString() + "; " + matchp3_1.Groups[0].Value.ToString() + "; " + matchp3_1.Groups[2].Value.ToString());
rssi.Flush();
}
// Specific Phantom 3 (MAC : 415CAF)
else if (matchp3_2.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-DJI_Phantom_3_STD" + "; " + matchp3_2.Groups[1].Value.ToString() + "; " + matchp3_2.Groups[0].Value.ToString() + "; " + matchp3_2.Groups[2].Value.ToString());
rssi.Flush();
}
// Specific Phantom 3 (MAC : 078D3E)
else if (matchp3_3.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-DJI_Phantom_3_STD" + "; " + matchp3_3.Groups[1].Value.ToString() + "; " + matchp3_3.Groups[0].Value.ToString() + "; " + matchp3_3.Groups[2].Value.ToString());
rssi.Flush();
}
// General Phantom 3
else if (matchp3.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Drone-DJI_Phantom_3_STD" + "; " + matchp3.Groups[1].Value.ToString() + "; " + matchp3.Groups[0].Value.ToString() + "; " + matchp3.Groups[2].Value.ToString());
rssi.Flush();
}
// WIFI
else if (matchAH.Success && matchAH2.Success)
{
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
rssi.WriteLine(formattedTime + "; " + "Wifi -" + matchAH2.Groups[3].Value.ToString() + "; " + matchAH.Groups[1].Value.ToString() + "; " + matchAH.Groups[0].Value.ToString() + "; " + matchAH.Groups[2].Value.ToString());
rssi.Flush();
}
}
}
Class B :-
public void DisplayOnDataGridView(DataGridView dl, GMapControl gmap, string TCPRSSIfile, string UDPRSSIfile)
{
//================================[TCP/IP]==================================================//
using (StreamReader streamReader = new StreamReader(TCPRSSIfile, true))
{
string line = String.Empty;
while ((line = streamReader.ReadLine()) != null)
{
Regex Search = new Regex(#"^(\S+ \S+); (\S+ -)(\S+); (\S+); (\S+); (\S+)");
Match matchSearch = Search.Match(line);
var time = DateTime.Now;
string formattedTime = time.ToString("yyyy/MM/dd HH:mm:ss");
StringBuilder sb = new StringBuilder();
if (matchSearch.Groups[3].Value.ToString() != null)
{
for (int i = 0; i <= matchSearch.Groups[3].Value.ToString().Length - 2; i += 2)
{
//Convert Hex format to standard ASCII string
sb.Append(Convert.ToString(Convert.ToChar(Int32.Parse(matchSearch.Groups[3].Value.ToString().Substring(i, 2), System.Globalization.NumberStyles.HexNumber))));
}
}
StringBuilder sbwifi = new StringBuilder(sb.Length);
foreach (char c in sb.ToString())
{
if ((int)c > 127) // 127 = Delete
continue;
if ((int)c < 32) // 1-31 = Control Character
continue;
if (c == ',')
continue;
if (c == '"')
continue;
sbwifi.Append(c);
}
Regex wifi = new Regex(#"^(\S+)\$");
Match matchwifi = wifi.Match(sbwifi.ToString());
if (matchwifi.Success)
{
sbwifi.Clear();
sbwifi.Append(matchwifi.Groups[1].Value.ToString());
}
if (matchSearch.Success)
{
try
{
if (dl.Rows.Count == 0)
{
if (matchSearch.Groups[2].Value.ToString().Contains("Wifi"))
{
using (StreamWriter rssi = new StreamWriter(#"D:\Skydroner\SearchReport.txt", true))
{
string DroneNameNoEmptySpace = matchSearch.Groups[2].Value.ToString().Replace(" ", String.Empty) + sbwifi.ToString().Replace(" ", String.Empty);
string DroneIDNoEmptySpace = matchSearch.Groups[4].Value.ToString().Replace(" ", String.Empty);
rssi.WriteLine(formattedTime + " " + DroneNameNoEmptySpace + " " + DroneIDNoEmptySpace + " Detected");
}
string[] newlist = new string[] { matchSearch.Groups[2].Value.ToString() + " " + sbwifi.ToString(), matchSearch.Groups[4].Value.ToString(), matchSearch.Groups[1].Value.ToString(), "Add", "Distract", "", "" };
dl.Rows.Add(newlist);
dl.Rows[rownumber].Cells["Inject"].Style.BackColor = Color.DarkGray;
//DetectedZone(gmap, false);
Image img = Image.FromFile(#"D:\Image\no_status.PNG");
dl.Rows[rownumber].Cells["DroneStatus"].Value = img;
}
else
{
string[] newlist = new string[] { matchSearch.Groups[3].Value.ToString(), matchSearch.Groups[4].Value.ToString(), matchSearch.Groups[1].Value.ToString(), "Add", "Distract", "", "" };
dl.Rows.Add(newlist);
dl.Rows[rownumber].Cells["Inject"].Style.BackColor = Color.LightGreen;
//DetectedZone(gmap, true);
Image img = Image.FromFile(#"D:\Image\no_status.PNG");
dl.Rows[rownumber].Cells["DroneStatus"].Value = img;
}
dl.Rows[rownumber].Cells["Whitelist"].Style.BackColor = Color.LightGray;
RSSI_Signal(dl, matchSearch.Groups[6].Value.ToString(), rownumber);
rownumber = rownumber + 1;
}
else
{
for (int row = 0; row < dl.Rows.Count; row++)
{
if (dl.Rows[row].Cells["DroneID"].Value.ToString() == matchSearch.Groups[4].Value.ToString())
{
if (matchSearch.Groups[2].Value.ToString().Contains("Wifi") == false)
{
Image img1 = Image.FromFile(#"D:\Image\alert.PNG");
if (dl.Rows[row].Cells["DroneStatus"].Value != img1)
{
dl.Rows[row].Cells["DroneStatus"].Value = img1;
}
}
dl.Rows[row].Cells["TimeDetected"].Value = matchSearch.Groups[1].Value.ToString();
RSSI_Signal(dl, matchSearch.Groups[6].Value.ToString(), rownumber);
duplicate = true;
}
}
if (!duplicate)
{
if (matchSearch.Groups[2].Value.ToString().Contains("Wifi"))
{
using (StreamWriter rssi = new StreamWriter(#"D:\Skydroner\SearchReport.txt", true))
{
string DroneNameNoEmptySpace = matchSearch.Groups[2].Value.ToString().Replace(" ", String.Empty) + sbwifi.ToString().Replace(" ", String.Empty);
string DroneIDNoEmptySpace = matchSearch.Groups[4].Value.ToString().Replace(" ", String.Empty);
rssi.WriteLine(formattedTime + " " + DroneNameNoEmptySpace + " " + DroneIDNoEmptySpace + " Detected");
}
string[] newlist = new string[] { matchSearch.Groups[2].Value.ToString() + " " + sbwifi.ToString(), matchSearch.Groups[4].Value.ToString(), matchSearch.Groups[1].Value.ToString(), "Add", "Distract", "", "" };
dl.Rows.Add(newlist);
dl.Rows[rownumber].Cells["Inject"].Style.BackColor = Color.DarkGray;
//DetectedZone(gmap, false);
Image img = Image.FromFile(#"D:\Image\no_status.PNG");
dl.Rows[rownumber].Cells["DroneStatus"].Value = img;
}
else
{
string[] newlist = new string[] { matchSearch.Groups[3].Value.ToString(), matchSearch.Groups[4].Value.ToString(), matchSearch.Groups[1].Value.ToString(), "Add", "Distract", "", "" };
dl.Rows.Add(newlist);
dl.Rows[rownumber].Cells["Inject"].Style.BackColor = Color.LightGreen;
//DetectedZone(gmap, true);
Image img = Image.FromFile(#"D:\Image\no_status.PNG");
dl.Rows[rownumber].Cells["DroneStatus"].Value = img;
}
dl.Rows[rownumber].Cells["Whitelist"].Style.BackColor = Color.LightGray;
RSSI_Signal(dl, matchSearch.Groups[6].Value.ToString(), rownumber);
rownumber = rownumber + 1;
}
}
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
else
{
// Do Nothing
}
}
}
//========================================[UDP]===================================================//
using (StreamReader streamReader = new StreamReader(UDPRSSIfile))
{
string line = String.Empty;
while ((line = streamReader.ReadLine()) != null)
{
Regex Search = new Regex(#"^(\S+ \S+); (\S+); (\S+); (\S+); (\S+)");
Match matchSearch = Search.Match(line);
if (matchSearch.Success)
{
try
{
//if (matchSearch.Groups[4].Value.ToString() != "0.000000")
//{
string[] newlist = new string[] { matchSearch.Groups[2].Value.ToString(), matchSearch.Groups[3].Value.ToString(), matchSearch.Groups[1].Value.ToString(), "Add", "Distract", "", "" };
dl.Rows.Add(newlist);
//}
dl.Rows[rownumber].Cells["Whitelist"].Style.BackColor = Color.LightGray;
if (dl.Rows[rownumber].Cells["DroneType"].Value.ToString().Contains("Wifi"))
{
dl.Rows[rownumber].Cells["Inject"].Style.BackColor = Color.DarkGray;
DetectedZone(gmap, false);
}
else
{
dl.Rows[rownumber].Cells["Inject"].Style.BackColor = Color.LightGreen;
DetectedZone(gmap, true);
}
Image img = Image.FromFile(#"D:\Image\arrow.jpg");
dl.Rows[rownumber].Cells["DroneStatus"].Value = img;
RSSI_Signal(dl, matchSearch.Groups[5].Value.ToString(), rownumber);
rownumber = rownumber + 1;
}
catch (Exception e)
{
Console.WriteLine(e.ToString());
}
}
else
{
// Do Nothing
}
}
}
// Add Number for Each DataGridView Row
if (null != dl)
{
foreach (DataGridViewRow r in dl.Rows)
{
dl.Rows[r.Index].HeaderCell.Value = (r.Index + 1).ToString();
}
}
}
Main Form :-
//========Call Class A Object==============//
private void button2_Click(object sender, EventArgs e)
{
// TCP/IP Address - Debug TCP Text File - Debug UDP Text File - UDP Port Number - TCP/IP RSSI Text File - UDP RSSI Text File
ListeningPole lp1 = new ListeningPole();
lp1.PortConnect("192.168.1.133", #"D:\Skydroner\SkyDroner_DebugTCP_1.txt", #"D:\Skydroner\SkyDroner_DebugUDP_1.txt", 61557, #"D:\Skydroner\SkyDroner_TCP_RSSI_1.txt", #"D:\Skydroner\SkyDroner_UDP_RSSI_1.txt");
}
//========Timer to Run Class B Object==============//
private void MainForm_Load(object sender, EventArgs e)
{
// Start Timer for Display Scroll Mouse Message
RowCountTimer.Interval = 1000;
RowCountTimer.Start();
}
private void RowCountTimer_Tick(object sender, EventArgs e)
{
Display dp1 = new Display();
dp1.DisplayOnDataGridView(DroneList, gmap, #"D:\Skydroner\SkyDroner_TCP_RSSI_1.txt", #"D:\Skydroner\SkyDroner_UDP_RSSI_1.txt");
}
Anyone have any solution for this error.
Please help.
Thanks.

Make sure to call Close() on the writer to close it before reading. I've seen instances where utilizing a using block with the writer may not close it in time for the reader to be able to read it.

WPF C# Progress Bar different Window [closed]

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Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 6 years ago.
Improve this question
I´m trying to figure out how to implement a progress bar in my application.
I´ve read some articles like this How to correctly implement a BackgroundWorker with ProgressBar updates?, and I caught how it works. My doubt is how will I call and update the progressbar.xaml since I´m executing the sql in the PendenciaController.cs.
PendenciaConsulta.xaml.cs
Task.Factory.StartNew(() =>
{
Progress<long> progress = null;
progress = new Progress<long>((i) =>
{
try
{
Dispatcher.Invoke(() => { PBar.Value = i; });
}
catch { }
});
pendenciaController = new PendenciaController(progress);
pendenciaController.PendenciaConsultar((bool)chkFollowUp.IsChecked); //The error occurs here
pendenciaController.PopularListas();
StatusController statusController = new StatusController();
ObservableCollection<Status> ListaStatus = null;
dataContext = new DataContext();
this.listaPendencia = this.pendenciaController.ListaPendencia;
ListaStatus = statusController.StatusConsultar();
this.DataContext = dataContext;
dtgPendencia.ItemsSource = this.listaPendencia;
lblQuantidadeRegistros.Content = "Quantidade de registros: " + this.listaPendencia.Count;
PopularCombos();
});
PendenciaController.cs
private Progress<long> _progress;
public PendenciaController(Progress<long> progress)
{
_progress = progress;
}
public void PendenciaConsultar(bool followUp)
{
OleDbConnection conn = null;
#region Select e conversão do DataSet
try
{
conn = new OleDbConnection(Conexao.getConexao());
conn.Open();
//Select da tabela tblPendencia
StringBuilder cmd = new StringBuilder();
cmd.Append("SELECT P.pendenciaId, " +
" P.contrato, " +
" P.adAm, " +
" P.diasDecorridos, " +
" P.corretora, " +
" P.produto, " +
" P.clienteNome, " +
" P.clienteCnpj, " +
" P.aberturaData, " +
" P.pendenciaTipo, " +
" P.lastro, " +
" P.garantiaDescricao, " +
" P.observacao, " +
" P.vencimentoData, " +
" P.liquidacaoData, " +
" P.rating, " +
" P.operacaoValor, " +
" P.pendenciaNivel, " +
" P.pendenciaValorFator, " +
" P.porContrato, " +
" P.officer, " +
" P.centroCusto, " +
" P.isCritico, " +
" P.statusId, " +
" P.clienteGrupo, " +
" P.followUp, " +
" P.carenciaInicio, " +
" P.carenciaFim, " +
" P.moeda, " +
" P.documentoTipo, " +
" P.tipo, " +
" (SELECT S.statusDescricao " +
" FROM tblStatus S " +
" WHERE S.statusId = P.statusId) as statusDescricao" +
" FROM tblPendencia P");
if (!followUp)
{
cmd.Append(" WHERE ((P.followUp <= NOW()) " +
" OR (P.followUp IS NULL))");
}
else
{
cmd.Append(" WHERE ((P.followUp <= NOW()) " +
" OR (P.followUp >= NOW()) " +
" OR (P.followUp IS NULL))");
}
OleDbDataAdapter da = new OleDbDataAdapter(cmd.ToString(), conn);
DataSet ds = new DataSet();
da.Fill(ds, "tblPendencia");
DataTable dt = new DataTable();
dt = ds.Tables["tblPendencia"];
Pendencia pendencia = null;
this.ListaPendencia = new List<Pendencia>();
if (ds.Tables != null && ds.Tables[0].Rows.Count > 0)
{
//foreach (DataRow dtRow in ds.Tables[0].Rows)
for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
{
DataRow dtRow = ds.Tables[0].Rows[i];
pendencia = new Pendencia();
pendencia.AberturaData = dtRow["aberturaData"].ToString();
pendencia.AdAm = dtRow["adAm"].ToString();
pendencia.CentroCusto = dtRow["centroCusto"].ToString();
pendencia.ClienteCnpj = dtRow["clienteCnpj"].ToString();
pendencia.ClienteNome = dtRow["clienteNome"].ToString();
pendencia.Contrato = dtRow["contrato"].ToString();
pendencia.Corretora = dtRow["corretora"].ToString();
pendencia.DiasDecorridos = dtRow["diasDecorridos"].ToString();
pendencia.GarantiaDescricao = dtRow["garantiaDescricao"].ToString();
pendencia.Lastro = dtRow["lastro"].ToString();
pendencia.LiquidacaoData = dtRow["liquidacaoData"].ToString();
pendencia.Observacao = dtRow["observacao"].ToString();
pendencia.Officer = dtRow["officer"].ToString();
pendencia.OperacaoValor = dtRow["operacaoValor"].ToString();
pendencia.PendenciaId = Convert.ToInt32(dtRow["pendenciaId"]);
pendencia.PendenciaNivel = dtRow["pendenciaNivel"].ToString();
pendencia.PendenciaValorFator = dtRow["pendenciaValorFator"].ToString();
pendencia.StatusId = String.IsNullOrEmpty(dtRow["statusId"].ToString()) ? 0 : Convert.ToInt32(dtRow["statusId"]);
pendencia.Produto = dtRow["produto"].ToString();
pendencia.Rating = dtRow["rating"].ToString();
pendencia.PendenciaTipo = dtRow["pendenciaTipo"].ToString();
pendencia.VencimentoData = dtRow["vencimentoData"].ToString();
pendencia.ClienteGrupo = dtRow["clienteGrupo"].ToString();
pendencia.FollowUp = dtRow["followUp"].ToString();
pendencia.CarenciaInicioData = dtRow["carenciaInicio"].ToString();
pendencia.CarenciaFimData = dtRow["carenciaFim"].ToString();
pendencia.DocumentoTipo = dtRow["documentoTipo"].ToString();
pendencia.StatusDescricao = dtRow["statusDescricao"].ToString();
pendencia.PorContratoDescricao = dtRow["porContrato"].ToString();
pendencia.Moeda = dtRow["moeda"].ToString();
pendencia.Tipo = dtRow["tipo"].ToString();
pendencia.IsCritico = Convert.ToBoolean(dtRow["isCritico"]);
pendencia.StatusId = String.IsNullOrEmpty(dtRow["statusId"].ToString()) ? 0 : Convert.ToInt32(dtRow["statusId"]);
this.ListaPendencia.Add(pendencia);
((IProgress<long>)(_progress)).Report((long)i);
}
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
finally { conn.Close(); }
#endregion
}
Thanks.

You should use Progress<T> Class and Task.
Example :
public partial class Window25 : Window
{
public Window25()
{
InitializeComponent();
}
private void Button_Click_1(object sender, RoutedEventArgs e)
{
Task.Factory.StartNew(() =>
{
Progress<long> progress = null;
progress = new Progress<long>((i) =>
{
try
{
// Update ProgressBar
Dispatcher.Invoke(() => { PBar.Value = i; });
}
// handle pre-mature closing of window (task cancellation)
catch { }
});
Controller c = new Controller(progress);
c.Do();
}
);
}
}
public class Controller
{
Progress<long> _progress;
public Controller(Progress<long> progress)
{
_progress = progress;
}
public void Do()
{
for (long s = 0; s < 99999; ++s)
((IProgress<long>)(_progress)).Report((long)s);
}
}
Progress class
Async in 4.5: Enabling Progress and Cancellation in Async APIs
See if this solves your problem.

In my opinion you should raise progress events from PendenciaController and handle them into PendenciaConsulta to update the ProgressBar.

C# WCF Multiple clients receive all the same data

my problem is that i have a WCF Service and multip
le clients can connect/subscribe to that service and get all Random Data
trough Callback with the service...a Timer starts when a clients subscribed to the service, the thing is that every client then gets all not the same data but thats what i want to achieve...what am i doing wrong?
This is what happens when one client subscribed to the service:
public SubscribeResult Subscribe()
{
SubscribeResult retVal = new SubscribeResult();
try
{
retVal.ClientID = Guid.NewGuid().ToString();
clientID = retVal.ClientID;
ServiceCallback = OperationContext.Current.GetCallbackChannel<ITraceCallback>();
ti = new Timer();
ti.Elapsed += Ti_Elapsed;
ti.Interval = 1000;
ti.Enabled = true;
ti.Start();
retVal.Success = true;
SubscribeClientList.Add(new SubscribeItem {CLIENTID = clientID, SENT = true });
connectedClients += 1;
}
catch (Exception ex)
{
retVal.Success = false;
Console.WriteLine("Something went horribly wrong! \n" + ex.Message);
}
return retVal;
}
And this is what happens when the timer hits zero :
private void Ti_Elapsed(object sender, ElapsedEventArgs e)
{
try
{
if (isSending == false)
{
isSending = true;
// generate message
CreateRandomString crs = new CreateRandomString();
string msg = crs.CreateString(rnd.Next(15, 25));
// increase entry
entry += 1;
// create timestamp of creation
DateTime creation = DateTime.Now;
// generate level
int muchwow = rnd.Next(1, 4);
string lvl = "undefined";
switch (muchwow)
{
case 1:
lvl = "Error";
break;
case 2:
lvl = "Warning";
break;
case 3:
lvl = "Information";
break;
}
bool sucess = ServiceCallback.Message(entry, creation, lvl, msg);
if (sucess == true)
{
CreateRandomString messagePreview = new CreateRandomString();
string prev = messagePreview.TruncString(msg, 20);
Console.WriteLine("[" + DateTime.Now + "] : [" + clientID + "] : " + "'" + prev + "' : " + "(" + lvl + ")");
sucess = false;
}
isSending = false;
}

Null Reference : Object reference not set to an instance of an object

I have a code for serial communication, with this code im sending values from textboxes to an device or when im testing to another PC. But when I press my "Program" button I get this error.
System.NullReferenceException was unhandled
Object reference not set to an instance of an object.
And i can catch the exception with an try catch but then i wont send my values to the device connected to my port.
This is my code:
public partial class MainForm : Form
{
private Settings _settings;
private SettingsIniFile _settingsIniFile = new SettingsIniFile();
private StringList _baudratelist = new StringList();
private StringList _systemPorts = new StringList();
private StringList _comportList = new StringList();
private Timer _comtimer = new Timer();
private ComPort _comport;
public MainForm()
{
InitializeComponent();
SetBaudrate();
LoadSettings(false);
LoadTextBoxes();
LoadComportName();
_comtimer.Tick += OnComtimerOnTick;
_comtimer.Interval = 2000;
_comtimer.Start();
LoadComportName();
Thread.Sleep(1000);
var portname = GetCurrentComPort();
if (portname != null)
{
_comport = new ComPort("COM6", 9600);
}
//var portname = GetCurrentComPort();
}
private String GetCurrentComPort()
{
int index = _comPortComboBox.SelectedIndex;
if (index < 0)
return null;
return _comportList[index];
}
private void OnComtimerOnTick(object sender, EventArgs args)
{
foreach (var item in SerialPort.GetPortNames())
{
if (!_systemPorts.Contains(item))
{
_comtimer.Stop();
_systemPorts.Add(item);
LoadComportName();
//MessageBox.Show("The new device is connected to" + item);
_comtimer.Start();
}
}
}
private void LoadSettings(bool defaults)
{
SettingsIniFile iniFile = new SettingsIniFile();
_settings = iniFile.LoadSettings(defaults);
}
private void SaveSettings()
{
SaveTextBoxes();
_settingsIniFile.Save(_settings);
}
private void LoadTextBoxes()
{
//ACR
_startRemovalTextBox.Text = _settings.AcrStartRemoval11;
_removalTimeTextBox.Text = _settings.AcrRemovalTime12;
_removalDelayTextBox.Text = _settings.AcrRemovalDelay13;
//CLEANING
_durCleaningTextbox.Text = _settings.CleanDurCleaning21;
_timeValveOnTextbox.Text = _settings.CleanTimeValveOn22;
_timeValveOffTextBox.Text = _settings.CleanTimeValveOff23;
//CALIBRATE
_contentLeftTextBox.Text = _settings.CalibrateContentLeft31;
_calibrateLeftTextBox.Text = _settings.CalibrateCalibrateLeft33;
_contentRightTextBox.Text = _settings.CalibrateContentRight32;
_calibrateRightTextBox.Text = _settings.CalibrateCalibrateRight34;
//CONDUCTIVITY
_factorLeftTextBox.Text = _settings.ConductFactorLeft41;
_offsetLeftTextBox.Text = _settings.ConductOffsetleft42;
_factorRightTextBox.Text = _settings.ConductFactorRight43;
_offsetRightTextBox.Text = _settings.ConductOffsetRight44;
_levelLeftTextBox.Text = _settings.ConductLevelLeft45;
_levelRightTextBox.Text = _settings.ConductLevelRight46;
//GENERAL
_typeOfValveTextBox.Text = _settings.GeneralTypeOfValve51;
_indicatorTextBox.Text = _settings.GeneralIndicator52;
_inverseOutputTextBox.Text = _settings.GeneralInverseOutput53;
_restartTimeTextBox.Text = _settings.GeneralRestartTime54;
_waterTimeTextBox.Text = _settings.GeneralWaterTime55;
_gateDelayTextbox.Text = _settings.GeneralGateDelay56;
//PULSATION
_pulsationTextBox.Text = _settings.PulsationPulsationPm61;
_ratioFrontTextBox.Text = _settings.PulsationSrRatioFront62;
_ratioBackTextBox.Text = _settings.PulsationSrRatioBack63;
_stimulationTextBox.Text = _settings.PulsationStimulationPm64;
_stimFrontTextBox.Text = _settings.PulsationSrStimFront65;
_stimBackTextBox.Text = _settings.PulsationSrStimBack66;
_stimulationDurTextBox.Text = _settings.PulsationStimulationDur67;
//return _settings;
}
private void SaveTextBoxes()
{
//ACR
_settings.AcrStartRemoval11 = _startRemovalTextBox.Text;
_settings.AcrRemovalTime12 = _removalTimeTextBox.Text;
_settings.AcrRemovalDelay13 = _removalDelayTextBox.Text;
//CLEANING
_settings.CleanDurCleaning21 = _durCleaningTextbox.Text;
_settings.CleanTimeValveOn22 = _timeValveOnTextbox.Text;
_settings.CleanTimeValveOff23 = _timeValveOffTextBox.Text;
//CALIBRATE
_settings.CalibrateContentLeft31 = _contentLeftTextBox.Text;
_settings.CalibrateCalibrateLeft33 = _calibrateLeftTextBox.Text;
_settings.CalibrateContentRight32 = _contentRightTextBox.Text;
_settings.CalibrateCalibrateRight34 = _calibrateRightTextBox.Text;
//CONDUCTIVITY
_settings.ConductFactorLeft41 = _factorLeftTextBox.Text;
_settings.ConductOffsetleft42 = _offsetLeftTextBox.Text;
_settings.ConductFactorRight43 = _factorRightTextBox.Text;
_settings.ConductOffsetRight44 = _offsetRightTextBox.Text;
_settings.ConductLevelLeft45 = _levelLeftTextBox.Text;
_settings.ConductLevelRight46 = _levelRightTextBox.Text;
//GENERAL
_settings.GeneralTypeOfValve51 = _typeOfValveTextBox.Text;
_settings.GeneralIndicator52 = _indicatorTextBox.Text;
_settings.GeneralInverseOutput53 = _inverseOutputTextBox.Text;
_settings.GeneralRestartTime54 = _restartTimeTextBox.Text;
_settings.GeneralWaterTime55 = _waterTimeTextBox.Text;
_settings.GeneralGateDelay56 = _gateDelayTextbox.Text;
//PULSATION
_settings.PulsationPulsationPm61 = _pulsationTextBox.Text;
_settings.PulsationSrRatioFront62 = _ratioFrontTextBox.Text;
_settings.PulsationSrRatioBack63 = _ratioBackTextBox.Text;
_settings.PulsationStimulationPm64 = _stimulationTextBox.Text;
_settings.PulsationSrStimFront65 = _stimFrontTextBox.Text;
_settings.PulsationSrStimBack66 = _stimBackTextBox.Text;
_settings.PulsationStimulationDur67 = _stimulationDurTextBox.Text;
}
private void DefaultSettingButtonClick(object sender, System.EventArgs e)
{
LoadSettings(true);
LoadTextBoxes();
SaveSettings();
LoadComportName();
}
private void SendSettingsButtonClick(object sender, System.EventArgs e)
{
var availablePorts = _systemPorts;
if (availablePorts != null && availablePorts.Any())
{
SaveSettings();
SendMessageTest();
}
else
{
_comPortComboBox.Text = "No Ports are available";
}
}
private void LoadComportName()
{
var availablePorts = _systemPorts;
_comPortComboBox.DataSource = null;
if (availablePorts != null && availablePorts.Any())
{
_comPortComboBox.DataSource = availablePorts;
}
else
{
_comPortComboBox.Text = "No Ports are available";
}
}
private void SetBaudrate()
{
_baudratelist.Add("4600");
_baudratelist.Add("9600");
_baudratelist.Add("19200");
}
private void SendMessageTest()
{
var Acrcontent = "[" + _acrNameLabel.Text + "]" + "\r\n" + _acrIdLabel11.Text + _startRemovalTextBox.Text + "\r\n"
+ _acrIdLabel12.Text + _removalTimeTextBox.Text + "\r\n" + _acrIdLabel13.Text +
_removalDelayTextBox.Text + "\r\n";
var Cleaningcontent ="["+ _cleaningNamelLabel.Text+"]" +"\r\n"+_cleaningIdLabel21.Text+
_durCleaningTextbox.Text + "\r\n"+ _cleaningLabelId22.Text+
_timeValveOnTextbox.Text + "\r\n"+ _cleaningLabelId23.Text+_timeValveOffTextBox.Text+"\r\n";
var Calibratecontent = "[" +_calibrateNameLabel.Text+ "]"+"\r\n"+_calibrateIDLabel31.Text+_contentLeftTextBox.Text+
"\r\n"+ _calibrateIDLabel32.Text+_calibrateLeftTextBox.Text+"\r\n"+_calibrateIDLabel33.Text+_contentRightTextBox.Text+
"\r\n" + _calibrateIDLabel34.Text + _calibrateRightTextBox.Text + "\r\n";
var Conductcontent = "[" + _conductName.Text + "]" + "\r\n" + _conductIdLabel41.Text + _factorLeftTextBox.Text +
"\r\n"
+ _conductIdLabel42.Text + _offsetLeftTextBox.Text + "\r\n" + _conductIdLabel43.Text +
_factorRightTextBox.Text + "\r\n"
+ _conductIdLabel44.Text + _offsetRightTextBox.Text + "\r\n" + _conductIdLabel45.Text +
_levelLeftTextBox.Text + "\r\n"
+ _conductIdLabel46.Text + _levelRightTextBox.Text + "\r\n";
var Generalcontent = "[" + _generalName.Text + "]" + "\r\n" + _generalIdLabel51.Text + _typeOfValveTextBox.Text +
"\r\n" +
_generalIdLabel52.Text + _indicatorTextBox.Text + "\r\n" + _generalIdLabel53.Text +
_inverseOutputTextBox.Text +
"\r\n" + _generalIdLabel54.Text + _restartTimeTextBox.Text + "\r\n" +
_generalIdLabel55.Text + _waterTimeTextBox.Text +
"\r\n" + _generalIdLabel56.Text + _gateDelayTextbox.Text + "\r\n";
var Pulsationcontent = "[" + _pulsationName.Text + "]" + "\r\n" + _pulsationIdLabel61.Text +
_pulsationTextBox.Text + "\r\n" +
_pulsationIdLabel62.Text + _ratioFrontTextBox.Text + "\r\n" +
_pulsationIdLabel63.Text + _ratioBackTextBox.Text + "\r\n" +
_pulsationIdLabel64.Text + _stimulationTextBox.Text + "\r\n" +
_pulsationIdLabel65.Text + _stimFrontTextBox.Text + "\r\n" +
_pulsationIdLabel66.Text + _stimBackTextBox.Text + "\r\n" + _pulsationIdLabel67.Text +
_stimulationDurTextBox.Text + "\r\n";
byte[] array = ComPort.StringToBytes(2+"\r\n"+Acrcontent+"\r\n"+Cleaningcontent + "\r\n" + Calibratecontent+"\r\n"+Conductcontent+"\r\n"+Generalcontent+"\r\n"+Pulsationcontent+3);
try
{
_comport.WriteBytes(array);
}
catch(Exception exc)
{
MessageBox.Show("Error {1}: "+ exc);
}
try
{
_comport.ReadBytes(array, array.Length, 1000);
}
catch(Exception exc)
{
MessageBox.Show("Error {2}" + exc);
}
//string result = Encoding.ASCII.GetString(array);
//MessageBox.Show(result);
}
}
This is my code for the communication:
namespace Communication
{
public class ComPort
{
private readonly SerialPort _serialPort;
public ComPort(string portname, int baudRate)
{
_serialPort = new SerialPort();
_serialPort.PortName = portname; <-----
_serialPort.BaudRate = baudRate;
_serialPort.StopBits = StopBits.One;
_serialPort.DataBits = 8;
_serialPort.Parity = Parity.None;
_serialPort.Handshake = Handshake.None;
// _serialPort.WriteBufferSize = 1;
_serialPort.DtrEnable = true;
_serialPort.RtsEnable = true;
_serialPort.Open();
_serialPort.ReadTimeout = 20000;
_serialPort.WriteTimeout = 20000;
}
public void Clear()
{
while (ReadByte() != -1)
continue;
}
private byte[] _array = new byte[] {0};
public void WriteByte(byte value)
{
_array[0] = value;
_serialPort.Write(_array, 0, 1);
// _serialPort.BaseStream.WriteByte(value);
_serialPort.BaseStream.Flush();
}
public void WriteBytes(byte[] array)
{
_serialPort.Write(array, 0, array.Length);
}
public void WriteBytes(byte[] array, int index, int length )
{
_serialPort.Write(array, index, length);
}
private int _readTimeOut = -1;
public int ReadByte(int timeOut = 200)
{
if (timeOut != _readTimeOut)
_serialPort.ReadTimeout = _readTimeOut = timeOut;
try
{
//return _serialPort.BaseStream.ReadByte();
return _serialPort.ReadByte();
// _serialPort.Read(array, 0, 1);
// return array[0];
}
catch (TimeoutException)
{
return -1;
}
}
public int ReadBytes(byte[] array, int length, int timeOut = 200)
{
if (timeOut != _readTimeOut)
_serialPort.ReadTimeout = _readTimeOut = timeOut;
try
{
//return _serialPort.BaseStream.ReadByte();
int bytesRead = 0;
while ( bytesRead < length )
bytesRead += _serialPort.Read(array, bytesRead, length - bytesRead);
// _serialPort.Read(array, 0, 1);
// return array[0];
return bytesRead;
}
catch (TimeoutException)
{
return -1;
}
}
/// <summary>
/// sends string followed by CR - LF
/// </summary>
/// <param name="line"></param>
public void WriteLine(String line)
{
WriteBytes(StringToBytes(line + "\r\n"));
}
public static byte[] StringToBytes(string input)
{
return Encoding.ASCII.GetBytes(input);
}
public void Close()
{
try
{
_serialPort.DtrEnable = false;
_serialPort.RtsEnable = false;
_serialPort.Close();
}
catch(IOException)
{
}
}
public bool Dtr
{
get { return _serialPort.DtrEnable; }
set { _serialPort.DtrEnable = value; }
}
public bool Rts
{
get { return _serialPort.RtsEnable; }
set { _serialPort.RtsEnable = value; }
}
}
}
Can someone explain to me what the problem is?
Thanks in advance
Possible anwser:
InitializeComponent();
SetBaudrate();
LoadSettings(false);
LoadTextBoxes();
LoadComportName();
_comtimer.Tick += OnComtimerOnTick;
_comtimer.Interval = 2000;
_comtimer.Start();
LoadComportName();
Thread.Sleep(1000);
var portname = GetCurrentComPort();
_comport = new ComPort("COM6", 9600);
But when i do this another error comes around the corner:
Value cannot be null.
Parameter name: PortName
This comes in the second piece of code where the arrow is.

Probably there is not comport selected at startup, so the _comport never gets created, you should check if the comport is created before you use is: if (_comport != null) ...
Update:
I think you should create a button instead of default connecting on a combobox selection change.
public void buttonConnect_Click(object sender, EventArgs e)
{
// check if the comport is created, else show a message and return,
TryDisconnect();
var portname = GetCurrentComPort();
if (portname == null)
return;
try
{
_comport = new ComPort(portname, 9600);
}
catch(Exception exception)
{
// try to create a better message here :-)
MessageBox.Show("Something went wrong....");
}
}
public void buttonDisconnect_Click(object sender, EventArgs e)
{
TryDisconnect();
}
public void TryDisconnect()
{
if( _comport != null)
{
_comport.Dispose();
_comport = null;
}
}
Also for this:
private void SendSettingsButtonClick(object sender, System.EventArgs e)
{
// check the _comPort instance first, if not assigned, leave a message..
if(_comPort == null)
{
MessageBox.Show("The comport is not initialized");
return;
}
var availablePorts = _systemPorts;
if (availablePorts != null && availablePorts.Any())
{
SaveSettings();
SendMessageTest();
}
else
{
_comPortComboBox.Text = "No Ports are available";
}
}
I got a tip for you, try to separate the markup/construction of the message, here how you could do.
I did not change all the code, only some examples:
I would create a struct/class to hold all information
public struct AcrContentInfo
{
public string AcrName;
public string AcrId11;
public string StartRemoval;
public string AcrId12;
public string RemovalTime;
public string AcrId13;
public string RemovalDelay;
// markup the information:
public override string ToString()
{
return string.Format(
"[{0}]\r\n{1}{2}\r\n{3}{4}\r\n{5}{6}\r\n",
AcrName,
AcrId11, StartRemoval,
AcrId12, RemovalTime,
AcrId13, RemovalDelay);
}
}
private void SendMessageTest()
{
// Instead of:
//var Acrcontent = "[" + _acrNameLabel.Text + "]" + "\r\n" + _acrIdLabel11.Text + _startRemovalTextBox.Text + "\r\n"
// + _acrIdLabel12.Text + _removalTimeTextBox.Text + "\r\n" + _acrIdLabel13.Text +
// _removalDelayTextBox.Text + "\r\n";
// I would use this instead, this way it wil be easier to maintain different versions.
// The code using the struct isn't responsible for markup
// Create the struct and fillin the fields.
AcrContentInfo acrContentInfo = new AcrContentInfo
{
AcrName = _acrNameLabel.Text,
AcrId11 = _acrIdLabel11.Text,
StartRemoval = _startRemovalTextBox.Text,
AcrId12 = _acrIdLabel12.Text,
RemovalTime = _removalTimeTextBox.Text,
AcrId13 = _acrIdLabel13.Text,
RemovalDelay = _removalDelayTextBox.Text
};
// if there is a new version of the protocol, you can create something like this
// AcrContentInfoV2 acrContentInfo = new AcrContentInfoV2
// call the tostring, (create a markup)
var Acrcontent = acrContentInfo.ToString();
// --- old code ---
var Cleaningcontent = "[" + _cleaningNamelLabel.Text + "]" + "\r\n" + _cleaningIdLabel21.Text +
_durCleaningTextbox.Text + "\r\n" + _cleaningLabelId22.Text +
_timeValveOnTextbox.Text + "\r\n" + _cleaningLabelId23.Text + _timeValveOffTextBox.Text + "\r\n";
var Calibratecontent = "[" + _calibrateNameLabel.Text + "]" + "\r\n" + _calibrateIDLabel31.Text + _contentLeftTextBox.Text +
"\r\n" + _calibrateIDLabel32.Text + _calibrateLeftTextBox.Text + "\r\n" + _calibrateIDLabel33.Text + _contentRightTextBox.Text +
"\r\n" + _calibrateIDLabel34.Text + _calibrateRightTextBox.Text + "\r\n";
var Conductcontent = "[" + _conductName.Text + "]" + "\r\n" + _conductIdLabel41.Text + _factorLeftTextBox.Text +
"\r\n"
+ _conductIdLabel42.Text + _offsetLeftTextBox.Text + "\r\n" + _conductIdLabel43.Text +
_factorRightTextBox.Text + "\r\n"
+ _conductIdLabel44.Text + _offsetRightTextBox.Text + "\r\n" + _conductIdLabel45.Text +
_levelLeftTextBox.Text + "\r\n"
+ _conductIdLabel46.Text + _levelRightTextBox.Text + "\r\n";
var Generalcontent = "[" + _generalName.Text + "]" + "\r\n" + _generalIdLabel51.Text + _typeOfValveTextBox.Text +
"\r\n" +
_generalIdLabel52.Text + _indicatorTextBox.Text + "\r\n" + _generalIdLabel53.Text +
_inverseOutputTextBox.Text +
"\r\n" + _generalIdLabel54.Text + _restartTimeTextBox.Text + "\r\n" +
_generalIdLabel55.Text + _waterTimeTextBox.Text +
"\r\n" + _generalIdLabel56.Text + _gateDelayTextbox.Text + "\r\n";
var Pulsationcontent = "[" + _pulsationName.Text + "]" + "\r\n" + _pulsationIdLabel61.Text +
_pulsationTextBox.Text + "\r\n" +
_pulsationIdLabel62.Text + _ratioFrontTextBox.Text + "\r\n" +
_pulsationIdLabel63.Text + _ratioBackTextBox.Text + "\r\n" +
_pulsationIdLabel64.Text + _stimulationTextBox.Text + "\r\n" +
_pulsationIdLabel65.Text + _stimFrontTextBox.Text + "\r\n" +
_pulsationIdLabel66.Text + _stimBackTextBox.Text + "\r\n" + _pulsationIdLabel67.Text +
_stimulationDurTextBox.Text + "\r\n";
// instad of:
//byte[] array = ComPort.StringToBytes(2+"\r\n"+Acrcontent+"\r\n"+Cleaningcontent + "\r\n" + Calibratecontent+"\r\n"+Conductcontent+"\r\n"+Generalcontent+"\r\n"+Pulsationcontent+3);
// I always try not to make very long lines of code.
// A stringbuilder is much more efficient building strings.
// I would:
StringBuilder sb = new StringBuilder();
sb.AppendLine("2");
sb.AppendLine("Acrcontent");
sb.AppendLine("Cleaningcontent");
sb.AppendLine("Calibratecontent");
sb.AppendLine("Conductcontent");
sb.AppendLine("Generalcontent");
sb.AppendLine("Pulsationcontent");
sb.AppendLine("3");
// why make the comport class responsible for the encoding type. _ComPort.StringToBytes_
byte[] array = Encoding.UTF8.GetBytes(sb.ToString());
try
{
_comport.WriteBytes(array);
// only read when write was succeed?
_comport.ReadBytes(array, array.Length, 1000);
}
catch (Exception exc)
{
MessageBox.Show("Error {1}: " + exc);
}
}
These are only my ideas, and meant to be constructive. (other point of view) Happy codeing..

You have to instantiate _comport before calling a method or accessing a property on it.
maybe in
var portname = GetCurrentComPort();
if (portname != null)
{
_comport = new ComPort("COM6", 9600);
}
portname is null then _comport not instantiated. you can trace it and check that if it has a value or not.

Yes assign a value to _comport like
_comport=null;