Develop Reference

Can I incorporate error handling into my API?

I have an API that loops through addresses and cleanses them. I am testing it with about 40k addresses, and it takes several hours to loop through thousands of them. Sometimes it throws an error and closes out the application and I have to start it over. Is there a way that I can write in error handling into the catch, that if there is an error, it will just log it, but continue running the app?
I am using VS 2019, C#, Windows Forms.
public class Elements
{
public string streetaddress1 { get; set; }
public string streetaddress2 { get; set; }
public string city { get; set; }
public string state { get; set; }
public string zip { get; set; }
public string country { get; set; }
}
void Output(string strDebugText)
{
try
{
System.Diagnostics.Debug.Write(strDebugText + Environment.NewLine);
txtResponse.Text = txtResponse.Text + strDebugText + Environment.NewLine;
txtResponse.SelectionStart = txtResponse.TextLength;
txtResponse.ScrollToCaret();
}
catch (Exception ex)
{
System.Diagnostics.Debug.Write(ex.Message, ToString() + Environment.NewLine);
}
}
private void btnMultiple_Click(object sender, EventArgs e)
{
//Loads address that need to be cleansed
string filePath = #"C:data.csv";
List<Elements> addresses = new List<Elements>();
List<string> lines = File.ReadAllLines(filePath).ToList();
foreach (var line in lines)
{
string[] entries = line.Split(',');
Elements newElement = new Elements();
newElement.streetaddress1 = entries[0];
newElement.streetaddress2 = entries[1];
newElement.city = entries[2];
newElement.state = entries[3];
newElement.zip = entries[4];
addresses.Add(newElement);
}
foreach (var Element in addresses)
{
Output($"{ Element.streetaddress1 } { Element.city} { Element.state } { Element.zip } " +
$"{ Element.country }");
var venvMulti = new AreaLookup.VertexEnvelope();
var clientMulti = new AreaLookup.LookupTaxAreasWS90Client();
var reqMulti = new AreaLookup.TaxAreaRequestType();
var reqresMulti = new AreaLookup.TaxAreaResultType();
var resMulti = new AreaLookup.TaxAreaResponseType();
string inputXMLMulti;
string outputXMLMulti;
var TALMulti = new AreaLookup.TaxAreaLookupType();
var TALasofDateMulti = new DateTime();
var resTypeMulti = new AreaLookup.TaxAreaLookupResultType();
var postalMulti = new AreaLookup.PostalAddressType();
string StrNoteMulti = "";
int i, y;
var x = default(int);
postalMulti.MainDivision = Element.state;
postalMulti.City = Element.city;
postalMulti.PostalCode = Element.zip;
postalMulti.StreetAddress1 = Element.streetaddress1;
TALasofDateMulti = Conversions.ToDate("2020-12-11");
TALMulti.asOfDate = TALasofDateMulti;
TALMulti.Item = postalMulti;
reqMulti.TaxAreaLookup = TALMulti;
var LITMulti = new AreaLookup.LoginType();
venvMulti.Login = new AreaLookup.LoginType();
venvMulti.Login.UserName = "****";
venvMulti.Login.Password = "****";
venvMulti.Item = reqMulti;
inputXMLMulti = (string)SerializeObjectToString(venvMulti);
Output(inputXMLMulti);
try
{
clientMulti.LookupTaxAreas90(ref venvMulti);
resMulti = (AreaLookup.TaxAreaResponseType)venvMulti.Item;
outputXMLMulti = (string)SerializeObjectToString(venvMulti);
Output(outputXMLMulti);
var loopTo = resMulti.TaxAreaResult.Length - 1;
}
catch (NullReferenceException)
{
Console.WriteLine("Null");
}
reqMulti = default;
reqresMulti = default;
resMulti = default;
void debugOutputCleansedMulti(string strDebugTextCleansedMulti)
{
try
{
System.Diagnostics.Debug.Write(strDebugTextCleansedMulti + Environment.NewLine);
txtCleansed.Text = txtCleansed.Text + strDebugTextCleansedMulti + Environment.NewLine;
txtCleansed.SelectionStart = txtCleansed.TextLength;
txtCleansed.ScrollToCaret();
}
catch (Exception ex)
{
System.Diagnostics.Debug.Write(ex.Message, ToString() + Environment.NewLine);
}
}
debugOutputCleansedMulti("Address Cleanse Started: ");
var venvCleansedMulti = new AreaLookup.VertexEnvelope();
var clientCleansedMulti = new AreaLookup.LookupTaxAreasWS90Client();
var reqCleansedMulti = new AreaLookup.TaxAreaRequestType();
var reqresCleansedMulti = new AreaLookup.TaxAreaResultType();
var resCleansedMulti = new AreaLookup.TaxAreaResponseType();
string inputXMLCleansedMulti;
string outputXMLCleansedMulti;
var TALCleansedMulti = new AreaLookup.TaxAreaLookupType();
var TALasofDateCleansedMulti = new DateTime();
var resTypeCleansedMulti = new AreaLookup.TaxAreaLookupResultType();
var postalCleansedMulti = new AreaLookup.PostalAddressType();
string StrNoteCleansedMulti = "";
int a, b;
var c = default(int);
postalCleansedMulti.MainDivision = Element.state;
postalCleansedMulti.City = Element.city;
postalCleansedMulti.PostalCode = Element.zip;
postalCleansedMulti.StreetAddress1 = Element.streetaddress1;
TALasofDateCleansedMulti = Conversions.ToDate("2020-12-11");
TALCleansedMulti.asOfDate = TALasofDateCleansedMulti;
TALCleansedMulti.Item = postalCleansedMulti;
reqCleansedMulti.TaxAreaLookup = TALCleansedMulti;
var LITCleansedMulti = new AreaLookup.LoginType();
venvCleansedMulti.Login = new AreaLookup.LoginType();
venvCleansedMulti.Login.UserName = "****";
venvCleansedMulti.Login.Password = "****";
venvCleansedMulti.Item = reqCleansedMulti;
int j = 1;
//inputXMLCleansed = resCleansed.TaxAreaResult[0].PostalAddress[0].StreetAddress1 + " - " + resCleansed.TaxAreaResult[0].PostalAddress[0].PostalCode + " - " + resCleansed.TaxAreaResult[0].confidenceIndicator;
//debugOutputCleansed(inputXMLCleansed);
try
{
clientCleansedMulti.LookupTaxAreas90(ref venvCleansedMulti);
resCleansedMulti = (AreaLookup.TaxAreaResponseType)venvCleansedMulti.Item;
debugOutputCleansedMulti(resCleansedMulti.TaxAreaResult[0].PostalAddress[0].StreetAddress1 + " | Street Address 1" + Environment.NewLine +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].StreetAddress2 + " | Street Address 2" + Environment.NewLine +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].SubDivision + " | County" + Environment.NewLine +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].City + " | City" + Environment.NewLine +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].PostalCode + " | Zip Code" + Environment.NewLine +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].MainDivision + " | State" + Environment.NewLine +
resCleansedMulti.TaxAreaResult[0].confidenceIndicator + " | Confidence Indicator");
string pathCleansed = #"C:\dev\data\data.csv";
string[] createText = {
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].StreetAddress1 + "," +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].StreetAddress2 + "," +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].City + "," +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].MainDivision + "," +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].PostalCode + "," +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].Country + "," +
resCleansedMulti.TaxAreaResult[0].PostalAddress[0].SubDivision + "," +
resCleansedMulti.TaxAreaResult[0].confidenceIndicator
};
File.AppendAllLines(pathCleansed, createText, System.Text.Encoding.UTF8);
txtCounter.Text = j.ToString();
j++;
var loopTo = resCleansedMulti.TaxAreaResult.Length - 1;
for (b = 0; b <= loopTo; b++)
{
if (c == 0)
{
StrNoteCleansedMulti = resCleansedMulti.TaxAreaResult[b].PostalAddress[0].StreetAddress1 + " - " + resCleansedMulti.TaxAreaResult[b].confidenceIndicator; c = 1;
}
else
{
StrNoteCleansedMulti += ", " + resCleansedMulti.TaxAreaResult[b].taxAreaId + " - " + resMulti.TaxAreaResult[b].confidenceIndicator;
}
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.Write(ex.Message, ToString() + Environment.NewLine);
}
reqCleansedMulti = default;
reqresCleansedMulti = default;
resCleansedMulti = default;
}
}

Essentially you need a way to save your work in progress. One pattern would be to load the file and store it in a database, then as you process each line you mark off which item you have processed. If you did this I would split the code into different modules, importing file, processing file, and exporting results.
Another simpler approach might be to write the results out as you process them, and record the line number from the input file. Then if you have to restart, find the last line you output and use that to skip reprocessing the items in your input file

How to fix 'The name 'k' does not exist in the current context' error?

I only get the System.IndexOutOfRangeException error when running the solution normally but is all okay when stepping into through the whole loop.
I have tried the to catch the exception but no joy.
private void button1_Click(object sender, EventArgs e)
{
for (int j = 0; j < jobs.Length; j++)
{
if (jobs[j].JobID == false)
{
for (int k = 0; k < threads.Length; k++)
{
if (threads[k] != null)
{
if (!(threads[k].ThreadState == ThreadState.Stopped) | !(threads[k].ThreadState == ThreadState.Unstarted))
{
continue;
}
}
try
{
threads[k] = new Thread(() => CountUp("ftp://ftp.net" + jobs[j].FTPFolder, HomePath + jobs[j].localFolder, j));
threads[k].Name = "Thread " + j + "¦ ID: " + threads[k].ManagedThreadId.ToString();
jobs[j].JobID = true;
//threads[k].Start();
break;
}
catch (Exception exception)
{
Console.WriteLine(exception);
throw;
}
}
}
}
StartThreads();
}
I expect all threads in the threads[] array to be initialised if jobs[].JobID is false.
Below is the CountUp() method:
private void CountUp(string ftppath,string localFile, int jobsID)
{
//string conf="";
NumberThreads++;
//string ftpPath = "ftp://ftp.Rxsystems.net" + conf.Split('¦')[1];
//string downloadPath = HomePath + conf.Split('¦')[0] + "\\";
string ftpPath = ftppath;
string downloadPath = localFile;
List<string> MSI = new List<string>(KD.FTP.Class.ListFiles(ftpPath,
FTPuser, FTPpass));
if (MSI.Count > 0)
{
KD.File.Class.Logger(Thread.CurrentThread.Name + ", " + MSI.Count + " Files in " + ftpPath, CurDir + "\\log.txt");
this.textBox1.AppendText(Thread.CurrentThread.Name + ", " + MSI.Count + " Files in " + ftpPath);
//this.textBox1.AppendText("\n\r");
int count = 0;
foreach (string ftpFile in MSI)
{
KD.FTP.Class.Download(ftpPath + ftpFile,downloadPath + "\\" + ftpFile, FTPuser,FTPpass);
count++;
KD.File.Class.Logger(Thread.CurrentThread.Name + ", " + "Downloaded " + count + "/" + MSI.Count + " Files - " + ftpFile, CurDir + "\\log.txt");
this.textBox1.AppendText(Thread.CurrentThread.Name + ", " + "Downloaded " + count + "/" + MSI.Count + " Files - " + ftpFile);
//this.textBox1.AppendText("\n\r");
}
}
NumberThreads--;
jobs[jobsID].JobID = false;
}
The below initialises threads[] and jobs[]:
private void Form1_Load(object sender, EventArgs e)
{
Form1.CheckForIllegalCrossThreadCalls = false;
if (File.Exists(CurDir + "\\FTPpaths.config"))
{
foreach (string line in File.ReadAllLines(CurDir + "\\FTPpaths.config"))
{
if (!string.IsNullOrEmpty(line))
{
ConfigPaths.Add(line.Split('¦')[0] + "¦" + line.Split('¦')[1]);
}
}
if (ConfigPaths.Count > 0)
{
jobs = new Jobs[ConfigPaths.Count];
for (int j = 0; j < ConfigPaths.Count; j++)
{
jobs[j] = new Jobs();
jobs[j].FTPFolder = ConfigPaths[j].Split('¦')[1];
jobs[j].localFolder = ConfigPaths[j].Split('¦')[0];
jobs[j].JobID = false;
}
threads = new Thread[jobs.Length];
}
timer1.Enabled = true;
}
else
{
Application.Exit();
}
}

From what I can see the problem is with j variable which is captured from closure into delegate passed to new Thread. It's well know problem when actual delegate execution references the variable in state after the loop execution so it's supposed to effectively contain jobs.Length value which is out of range. To fix you need to introduce a local variable inside the loop to copy j value in, and then use this variable instead of j as index of jobs inside the delegate passed to the Thread constructor:
try
{
var jobIdx = j;
threads[k] = new Thread(() => CountUp("ftp://ftp.net" + jobs[jobIdx].FTPFolder, HomePath + jobs[jobIdx].localFolder, jobIdx));
...
// other stuff
}
catch (Exception exception)
{
Console.WriteLine(exception);
throw;
}

Method not found: 'IntPtr System.Runtime.InteropServices.Marshal.GetFunctionPointerForDelegate(!!0)

I am using visual studio 2010 professional on windows 7 (32 bit) to connect to RFID reader LRU3000 and i encounterd this exception
Method not found: 'IntPtr
System.Runtime.InteropServices.Marshal.GetFunctionPointerForDelegate(!!0)
kindly download the sample from the following link.
I searched the web much but i failed to know what is wrong.
Thanks In advance
NotificationSample.zip
and this is the code of the sample
this is the code of the sample :
the exception occurs at the line of code :
try
{
reader.StartAsyncTask(FedmTaskOption.ID_NOTIFICATION, this, taskOpt);
}
catch (FeReaderDriverException ex)
{
MessageBox.Show(ex.ToString());
}
public partial class NotificationSample : Form,FedmTaskListener
{
FedmIscReader reader;
FedmTaskOption taskOpt;
long count=1;
//declaration from delegatetyp
public delegate void DelegateDisplayRecSets(int recSets,
byte[] type,
string[] serialNumber,
string[] dataBlock,
string[] date,
string[] time,
byte[] antennaNr,
Dictionary<byte, FedmIscRssiItem>[] dicRSSI,
byte[] input,
byte[] state,
string ip);
/// <summary>
/// Der Haupteinstiegspunkt für die Anwendung.
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new NotificationSample());
}
//Constructor
public NotificationSample()
{
InitializeComponent();
try
{
reader = new FedmIscReader();
reader.SetTableSize(FedmIscReaderConst.BRM_TABLE, 255); // max 255 tag with each notification
taskOpt = new FedmTaskOption();
}
catch(FedmException ex)
{
MessageBox.Show(ex.ToString());
return;
}
}
//Actualy Time propertie
private string Time
{
get
{
DateTime d;
d = DateTime.Now;
string t;
// Get the Date
if (d.Month.ToString().Trim().Length == 1)
{
t = "0" + d.Month.ToString().Trim() + "/";
}
else
{
t = d.Month.ToString().Trim() + "/";
}
if (d.Day.ToString().Trim().Length == 1)
{
t += "0" + d.Day.ToString().Trim() + "/";
}
else
{
t += d.Day.ToString().Trim() + "/";
}
t += d.Year.ToString().Trim() + " ";
// Get the time
if (d.Hour.ToString().Trim().Length == 1)
{
t += "0" + d.Hour.ToString().Trim() + ":";
}
else
{
t += d.Hour.ToString().Trim() + ":";
}
if (d.Minute.ToString().Trim().Length == 1)
{
t += "0" + d.Minute.ToString().Trim() + ":";
}
else
{
t += d.Minute.ToString().Trim() + ":";
}
if (d.Second.ToString().Trim().Length == 1)
{
t += "0" + d.Second.ToString().Trim() + ".";
}
else
{
t += d.Second.ToString().Trim() + ".";
}
if (d.Millisecond.ToString().Trim().Length == 1)
{
t += "00" + d.Millisecond.ToString().Trim() + ".";
}
else if (d.Millisecond.ToString().Trim().Length == 2)
{
t += "0" + d.Millisecond.ToString().Trim() + ".";
}
else
{
t += d.Millisecond.ToString().Trim() + ".";
}
return t;
}
}
/*****************************Methods from interface FedmTaskListener*******************/
public void OnNewNotification(int iError,string IP,uint PortNr)
{
int i;
FedmBrmTableItem[] brmItems;
brmItems = (FedmBrmTableItem[])reader.GetTable(FedmIscReaderConst.BRM_TABLE);
//declaration from delegateobject
DelegateDisplayRecSets DisplayRecSetMethod = new DelegateDisplayRecSets(DisplayRecSets);
object[] obj = new object[11];
IAsyncResult result;
if(brmItems == null)
{
return;
}
string[] serialnumber = new string[brmItems.Length];
string[] dataBlock = new string[brmItems.Length];
string[] date = new string[brmItems.Length];
string[] time = new string[brmItems.Length];
byte[] type = new byte[brmItems.Length];
byte[] antennaNr = new byte[brmItems.Length];
byte[] input = new byte[brmItems.Length];
byte[] state = new byte[brmItems.Length];
byte[] dbsize = new byte[brmItems.Length];
Dictionary<byte, FedmIscRssiItem>[] dicRSSI = new Dictionary<byte, FedmIscRssiItem>[brmItems.Length];
long dbn;
byte dbadr;
string db;
for (i = 0; i < brmItems.Length; i++)
{ // serial number
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_SNR))
{
brmItems[i].GetData(FedmIscReaderConst.DATA_SNR, out serialnumber[i]);
}
// data blocks
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_RxDB))
{
brmItems[i].GetData(FedmIscReaderConst.DATA_DBN, out dbn);
brmItems[i].GetData(FedmIscReaderConst.DATA_DB_ADR, out dbadr);
int j;
for (j = dbadr; j < dbn; j++)
{
brmItems[i].GetData(FedmIscReaderConst.DATA_RxDB, j, out db);
dataBlock[i] = dataBlock[i] + db + "\r\n"+"\t\t";
}
}
// Transponder Type
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_TRTYPE))
{
brmItems[i].GetData(FedmIscReaderConst.DATA_TRTYPE, out type[i]);
}
// Date
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_DATE))
{
date[i] = brmItems[i].GetReaderTime().GetDate();
}
// Time
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_TIMER))
{
time[i] = brmItems[i].GetReaderTime().GetTime();
}
// Antenna number
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_ANT_NR))
{
brmItems[i].GetData(FedmIscReaderConst.DATA_ANT_NR, out antennaNr[i]);
}
// RSSI value
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_ANT_RSSI))
{
dicRSSI[i] = brmItems[i].GetRSSI();
}
else
{
dicRSSI[i] = new Dictionary<byte, FedmIscRssiItem>();
}
// Input
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_INPUT))
{
brmItems[i].GetData(FedmIscReaderConst.DATA_INPUT, out input[i]);
brmItems[i].GetData(FedmIscReaderConst.DATA_STATE, out state[i]);
}
}
obj[0] = brmItems.Length;
obj[1] = type;
obj[2] = serialnumber;
obj[3] = dataBlock;
obj[4] = date;
obj[5] = time;
obj[6] = antennaNr;
obj[7] = dicRSSI;
obj[8] = input;
obj[9] = state;
obj[10] = IP;
result = (IAsyncResult)Invoke(DisplayRecSetMethod, obj);
}
public void OnNewApduResponse(int iError)
{
throw new Exception("The method or operation is not implemented.");
}
public void OnNewQueueResponse(int iError)
{
throw new Exception("The method or operation is not implemented.");
}
public void OnNewSAMResponse(int iError, byte[] responseData)
{
throw new Exception("The method or operation is not implemented.");
}
public void OnNewReaderDiagnostic(int iError,string IP,uint PortNr)
{
}
public int OnNewMaxAccessEvent(int iError, string maxEvent, string ip, uint portNr)
{
throw new Exception("The method or operation is not implemented.");
}
public int OnNewMaxKeepAliveEvent(int iError, uint uiErrorFlags, uint TableSize, uint uiTableLength, string ip, uint portNr)
{
throw new Exception("The method or operation is not implemented.");
}
public void OnNewTag(int iError)
{
}
public void onNewPeopleCounterEvent(uint counter1, uint counter2, uint counter3, uint counter4, string ip, uint portNr, uint busAddress)
{
throw new Exception("The method or operation is not implemented.");
}
/************************************ENDE***********************************************/
/******************************************************Asynchrone method*****************************************************************************************************/
public void DisplayRecSets( int recSets,
byte[] type,
string[] serialNumber,
string[] dataBlock,
string[] date,
string[] time,
byte[] antennaNr,
Dictionary<byte, FedmIscRssiItem>[] dicRSSI,
byte[] input,
byte[] state,
string ip)
{
Dictionary<byte, FedmIscRssiItem> RSSIval;
FedmIscRssiItem RSSIitem;
int i;
bool bcheck;
byte antNo;
string dr;
string tr = "";
FedmBrmTableItem[] brmItems;
brmItems = (FedmBrmTableItem[])reader.GetTable(FedmIscReaderConst.BRM_TABLE);
tr += "-----------------------------------------------------------------" + "\r\n";
tr += "DATE/TIME: " + Time.ToString() + "\r\n";
tr += "-----------------------------------------------------------------" + "\r\n";
count = 1;
for (i = 0; i < recSets; i++)
{
tr += (count).ToString().Trim() + "." + " TRANSPONDER" + "\r\n";
count = count + 1;
if (type[i] >= 0)
{
//just the two last bit
dr = "0x" + FeHexConvert.IntegerToHexString(type[i]).Substring(FeHexConvert.IntegerToHexString(type[i]).Length - 2, 2);
tr += "TR-TYPE:" + "\t" + dr.ToString() + "\r\n";
}
// Output SeriaNo.
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_SNR))
{
if (serialNumber[i] != null)
{
tr += "SNR:" + "\t\t" + serialNumber[i].ToString() + "\r\n";
}
}
// Output Data Blocks
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_RxDB))
{
if (dataBlock[i] != null)
{
tr += "DB:" + "\t\t" + dataBlock[i].ToString() + "\r\n";
}
}
// Output Date
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_TIMER) || brmItems[i].IsDataValid(FedmIscReaderConst.DATA_DATE))
{
if (date[i] != null)
{
tr += "DATE:" + "\t\t" + date[i].ToString() + "\r\n";
}
}
// Output Time
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_TIMER))
{
if (time[i] != null)
{
tr += "TIME:" + "\t\t" + time[i].ToString() + "\r\n";
}
}
// It is possible either to output the ANT_NR or the RSSI value (this is also important for the reader config!)
// Output ANT_NR
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_ANT_NR))
{
tr += "ANT. NR:"+"\t\t" + (antennaNr[i].ToString()).Trim() + "\r\n";
}
// It is possible either to output the ANT_NR or the RSSI value (this is also important for the reader config!)
// Output RSSI
if (dicRSSI.Length > 0)
{
if (dicRSSI[i] != null)
{
RSSIval = dicRSSI[i];
for(antNo = 1; antNo<FedmBrmTableItem.TABLE_MAX_ANTENNA; antNo++)
{
bcheck = RSSIval.TryGetValue(antNo, out RSSIitem);
if (!bcheck)
continue;
tr += "RSSI of AntNr. " + "\t" + antNo.ToString() + " is " + "-" + RSSIitem.RSSI.ToString() + "dBm" + "\r\n";
}
}
}
// Output INPUT
if (brmItems[i].IsDataValid(FedmIscReaderConst.DATA_INPUT))
{
tr += "INPUT:" + "\t\t" + (input[i].ToString()).Trim() + "\r\n";
tr += "STATE:" + "\t\t" + (state[i].ToString()).Trim() + "\r\n";
}
// Output IP where notification data comes from
tr += "FROM:" + "\t\t" + ip + "\r\n";
tr += "" + "\r\n";
tr += "" + "\r\n";
}
this.textBoxData.AppendText(tr);
tr = "";
}
/**********************************************************ENDE***************************************************************************************************************/
/**************************************************Buttons**********************************************/
private void buttonListen_Click(object sender, EventArgs e)
{
if(this.buttonListen.Text == "Listen")
{
this.buttonListen.Text = "Cancel";
taskOpt.IPPort = Convert.ToInt16(this.textBoxPortNr.Text);
if(this.checkBoxAkn.Checked)
{
taskOpt.NotifyWithAck = 1;
}
else
{
taskOpt.NotifyWithAck = 0;
}
//Start from intern Thread
try
{
reader.StartAsyncTask(FedmTaskOption.ID_NOTIFICATION, this, taskOpt);
}
catch (FeReaderDriverException ex)
{
MessageBox.Show(ex.ToString());
}
}
else
{
this.buttonListen.Text = "Listen";
//End from intern thread
int val;
reader.ResetTable(FedmIscReaderConst.BRM_TABLE);
val=reader.CancelAsyncTask();
//case Deadlocks ->-4084
if (val < 0)
{
reader.CancelAsyncTask();
}
}
}
private void buttonClear_Click(object sender, EventArgs e)
{
this.textBoxData.Clear();
count = 1;
}
/***********************************************************Ende******************************************/
private void NotificationSample_FormClosing(object sender, FormClosingEventArgs e)
{
reader.CancelAsyncTask();
Application.Exit();
}
}

System.Data.OleDb.OleDbException(0x80004005): Unspecified Error

Through a series of loops and Database calls (Select statements only) saved as datatables I am generating a .txt file with the values. It runs fine for a little while (19 rows...19 full loop cycles) then I get a runtime exception being thrown by connection.Open()
I have the entire loop inside a try catch block in order to catch the exception and produce the message then 2 blank lines then the stack trace.
I have tried to read this and figure out what to do but I am a bit of a Novice when it comes to DB connections. I have looked elsewhere but do not seem to find a question that quite fits my situation.
FYI: C# 4.0 Windows Form Application, Access DB
I am hoping to find some suggestions on where to begin looking. I am positive that my connection is closed when this error is thrown due to the validation i implemented as shown here:
internal IDbConnection GetConnection()
{
try
{
var connection = _assemblyProvider.Factory.CreateConnection();
connection.ConnectionString = _connectionString;
_connectionState = connection.State.ToString();
if (_connectionState == "Open")
GetConnection();
else
{
connection.Open();
}
return connection;
}
catch (Exception exept)
{
throw new Exception(exept.ToString() + "\n\n" + exept.StackTrace.ToString());
}
}
This method is being called from here:
public DataTable ExecuteDataTable(string commandText, string tableName, DbParameterCollection paramCollection, CommandType commandType)
{
DataTable dtReturn;
IDbConnection connection = null;
try
{
connection = _connectionManager.GetConnection();
dtReturn = _dbAdapterManager.GetDataTable(commandText, paramCollection, connection, tableName, commandType);
}
finally
{
if (connection != null)
{
connection.Close();
connection.Dispose();
}
}
return dtReturn;
}
public DataTable ExecuteDataTable(string commandText, string tableName, CommandType commandType)
{
return ExecuteDataTable(commandText, tableName, new DbParameterCollection(), commandType);
}
public DataTable ExecuteDataTable(string commandText)
{
return ExecuteDataTable(commandText, string.Empty, CommandType.Text);
}
and
//read from DB using a SQL statement and return a DataTable
internal static DataTable readDB(string SQL)
{
var dbHelper = new DbHelper();
using (IDbConnection connection = dbHelper.GetConnObject())
{
return dbHelper.ExecuteDataTable(SQL);
}
}
Here is the loop (its kinda long and could probably be done better but I just want to find why its breaking after its worked several times)
The exception is thrown from the line that Reads:
DataTable iRecNum2ClaimRecNumFromClaim = dbConnect.readDB(SQLString);
inside this:
SQLString = "SELECT * FROM Claim WHERE ClaimStatus <> 1";
DataTable allRecsFromClaimNotStatus1 = dbConnect.readDB(SQLString);
if (allRecsFromClaimNotStatus1.Rows.Count == 0)
return;
else
{
string path = txtExtractFileLocation.Text;
if (txtExtractFileLocation.Text.Substring(txtExtractFileLocation.Text.Length - 2) == "\\\\")
{
path = path.Substring(0, path.Length - 1);
}
if (path.Substring(path.Length - 1) == "\\")
path += "DI_Extract.txt";
else
path += #"\DI_Extract.txt";
using (StreamWriter sw = new StreamWriter(#path))
{
for (int i = 0; i < allRecsFromClaimNotStatus1.Rows.Count; i++)
{
rNum = allRecsFromClaimNotStatus1.Rows[i][2].ToString().Trim();//Claim.InsuredRecNum
SQLString = "SELECT * FROM Insured WHERE RecNum = " + rNum;
DataTable allInsuredByRecNum = dbConnect.readDB(SQLString);
lossDate = allRecsFromClaimNotStatus1.Rows[i][11].ToString().Trim();//Claim.LossDate
lossDate = (Convert.ToDateTime(lossDate)).Date.ToString("MM/dd/yyyy");
reportedDate = allRecsFromClaimNotStatus1.Rows[i][9].ToString().Trim();//Claim.ReportedDate
reportedDate = (Convert.ToDateTime(reportedDate)).Date.ToString("MM/dd/yyyy");
claim = allRecsFromClaimNotStatus1.Rows[i][0].ToString().Trim();//Claim.ClaimNumber
if (chkIncludePaymentsForCurrentMonth.Checked == true)
{
direct = allRecsFromClaimNotStatus1.Rows[i][4].ToString().Trim();//Claim.DirectReserve
WP = allRecsFromClaimNotStatus1.Rows[i][5].ToString().Trim();//Claim.WPReserve
ceded = allRecsFromClaimNotStatus1.Rows[i][6].ToString().Trim();//Claim.CededReserve
}
else
{
direct = allRecsFromClaimNotStatus1.Rows[i][29].ToString().Trim();//Claim.MonthEndDirect
WP = allRecsFromClaimNotStatus1.Rows[i][30].ToString().Trim();//Claim.MonthEndWP
ceded = allRecsFromClaimNotStatus1.Rows[i][31].ToString().Trim();//Claim.MonthEndCeded
}
ced = Convert.ToDecimal(ceded);
wav = Convert.ToDecimal(WP);
ceded = ced.ToString("#.##");
WP = wav.ToString("#.##");
if (ceded == "")
ceded = "0";
if (WP == "")
WP = "0";
if ((allRecsFromClaimNotStatus1.Rows[i][10].ToString().Trim() != null) &&
(allRecsFromClaimNotStatus1.Rows[i][10].ToString().Trim() != ""))//Claim.WaiverDate
{
onWaiver = "YES";
}
else
{
onWaiver = "NO";
}
reinsPreNotice = "NO";
reinsCeded = "NO";
switch (allRecsFromClaimNotStatus1.Rows[i][7].ToString().Trim())//Claim.CededPre
{
case "1":
{
reinsPreNotice = "YES";
break;
}
case "2":
{
reinsCeded = "YES";
break;
}
}//end switch
state = allRecsFromClaimNotStatus1.Rows[i][8].ToString().Trim();//Claim.LossState
lName = allInsuredByRecNum.Rows[0][1].ToString().Trim();//Insured.LastName
fName = allInsuredByRecNum.Rows[0][0].ToString().Trim();//Insured.FirstName
mi = allInsuredByRecNum.Rows[0][2].ToString().Trim();//Insured.MI
policy = allInsuredByRecNum.Rows[0][43].ToString().Trim();//Insured.PolicyNumber
DOB = allInsuredByRecNum.Rows[0][10].ToString().Trim();//Insured.DOB
DOB = (Convert.ToDateTime(DOB)).Date.ToString("MM/dd/yyyy");
age = allInsuredByRecNum.Rows[0][11].ToString().Trim();//Insured.TrueAge
issueAge = calculateAge(Convert.ToDateTime(allInsuredByRecNum.Rows[0][10].ToString().Trim()), //Insured.DOB
Convert.ToDateTime(allInsuredByRecNum.Rows[0][45].ToString().Trim()));//Insured.EffectiveDate
SQLString = "SELECT InsuredRecNum, RecNum FROM Claim WHERE InsuredRecNum = " + rNum;
DataTable iRecNum2ClaimRecNumFromClaim = dbConnect.readDB(SQLString);
rNum = iRecNum2ClaimRecNumFromClaim.Rows[0][1].ToString().Trim();
issueDate = allInsuredByRecNum.Rows[0][45].ToString().Trim();//Insured.EffectiveDate
issueDate = (Convert.ToDateTime(issueDate)).Date.ToString("MM/dd/yyyy");
sex = allInsuredByRecNum.Rows[0][13].ToString().Trim();//Insured.Gender
planCode = allInsuredByRecNum.Rows[0][44].ToString().Trim();//Insured.PlanMnemonic
issueAmt = allInsuredByRecNum.Rows[0][49].ToString().Trim();//Insured.BenefitAmount (Monthly Benefit Amount before Offset)
benefitPeriod = allInsuredByRecNum.Rows[0][50].ToString().Trim();//Insured.BenefitPeriod
if (allInsuredByRecNum.Rows[0][54].ToString().Trim().Length == 2)//Insured.EliminationPeriod
eliminationPeriod = "0" + allInsuredByRecNum.Rows[0][54].ToString().Trim();
else
eliminationPeriod = allInsuredByRecNum.Rows[0][54].ToString().Trim();
premiumAmount = allInsuredByRecNum.Rows[0][48].ToString().Trim();//Insured.AnnualPremium
occupationClass = allInsuredByRecNum.Rows[0][55].ToString().Trim();//Insured.OccupationClass
//select only status = EXEC (0)
SQLString = "SELECT * FROM Offset WHERE ClaimRecNum = " + rNum + " AND Status = 0";
DataTable allOffsetByClaimRecNumAndStatus0 = dbConnect.readDB(SQLString);
offsetAmt = 0;
dblSTDOffsetAmount = 0;
dblRecOffsetAmount = 0;
RECOffsetOcc = "0";
RECOffsetExecuted = "0";
int offsetCount = allOffsetByClaimRecNumAndStatus0.Rows.Count;
if (offsetCount != 0)
{
for (int j = 0; j < offsetCount; j++)
{
//accumulate standard offset (STD) and Recovery offset (REC)
if (allOffsetByClaimRecNumAndStatus0.Rows[0][1].ToString().Trim() == "0")//Offset.Type
{
//Standard Type
dblSTDOffsetAmount += Convert.ToDouble(allOffsetByClaimRecNumAndStatus0.Rows[j][4].ToString().Trim());//Offset.Amount
}
else
{
//Recovery type
dblRecOffsetAmount = Convert.ToDouble(allOffsetByClaimRecNumAndStatus0.Rows[j][4].ToString().Trim());//Offset.Amount
RECOffsetOcc = allOffsetByClaimRecNumAndStatus0.Rows[j][5].ToString().Trim();//Offset.Occurance
RECOffsetExecuted = allOffsetByClaimRecNumAndStatus0.Rows[j][6].ToString().Trim();//Offset.Executed
}//end if
}//end for loop
}//end if
STDOffsetAmount = dblSTDOffsetAmount.ToString();
RECOffsetAmount = dblRecOffsetAmount.ToString();
if (chkIncludePaymentsForCurrentMonth.Checked == true)
SQLString = "SELECT * FROM Payment WHERE InsuredRecNum = " + rNum + " AND IssueDate >= #01/01/" + DateTime.Today.Date.Year + "# AND IssueDate <= #" + DateTime.Today.Date.ToShortDateString() + "#";
else
SQLString = "SELECT * FROM Payment WHERE InsuredRecNum = " + rNum + " AND IssueDate >= #01/01/" + endDate.Substring(endDate.Length - 4) + "# AND IssueDate <= #" + Convert.ToDateTime(endDate).Date.ToShortDateString() + "#";
DataTable allPaymentByIRecNumAndIssDateInRange = dbConnect.readDB(SQLString);
YTDPmt = 0;
if (allPaymentByIRecNumAndIssDateInRange.Rows.Count == 0)
YTDPmt = 0;
else
{
int paymentCount = allPaymentByIRecNumAndIssDateInRange.Rows.Count;
double issAmt;
for (int k = 0; k < paymentCount; k++)
{
issAmt = Convert.ToDouble(allPaymentByIRecNumAndIssDateInRange.Rows[0][30].ToString().Trim());//Payment.IssueAmount
YTDPmt += issAmt;
}// end loop
}//end if
YTDPmts = YTDPmt.ToString();
if (chkIncludePaymentsForCurrentMonth.Checked == true)
SQLString = "SELECT * FROM Payment WHERE ClaimRecNum = " + rNum;
else
SQLString = "SELECT * FROM Payment WHERE ClaimRecNum = " + rNum + " AND IssueDate <= #" + Convert.ToDateTime(endDate).Date.ToShortDateString() + "#";
DataTable allPaymentByRNum = dbConnect.readDB(SQLString);
totalPmt = 0;
if (allPaymentByRNum.Rows.Count == 0)
totalPmt = 0;
else
{
double issAmt = Convert.ToDouble(allPaymentByRNum.Rows[0][30].ToString().Trim());
for (int m = 0; m < allPaymentByRNum.Rows.Count; m++)
{
totalPmt += issAmt;
}
}
allPmts = totalPmt.ToString();
//set spacing for output
string block1 = policy + claim + planCode;
block1 = setSpacing(block1, 28);
string block2 = setSpacing(benefitPeriod, 3) + eliminationPeriod + occupationClass;
block2 = setSpacing(block2, 11);
issueAmt = setSpacing(issueAmt, 8);
STDOffsetAmount = setSpacing(STDOffsetAmount, 8);
RECOffsetAmount = setSpacing(RECOffsetAmount, 8);
RECOffsetOcc = setSpacing(RECOffsetOcc, 3);
RECOffsetExecuted = setSpacing(RECOffsetExecuted, 3);
string block3 = lossDate + age;
block3 = setSpacing(block3, 13);
issueAge = setSpacing(issueAge, 3);
string block4 = issueDate + DOB + sex + onWaiver + premiumAmount;
block4 = setSpacing(block4, 32);
reinsPreNotice = setSpacing(reinsPreNotice, 3);
reinsCeded = setSpacing(reinsCeded, 4);
double ap = Convert.ToDouble(allPmts);
allPmts = ap.ToString("#.#");
allPmts = setSpacing(allPmts, 8);
YTDPmts = setSpacing(YTDPmts, 8);
lName = setSpacing(lName, 19);
fName = fName + " " + mi;
fName = setSpacing(fName, 20);
string block5 = state + direct;
block5 = setSpacing(block5, 10);
ceded = setSpacing(ceded, 8);
WP = setSpacing(WP, 8);
reportedDate = setSpacing(reportedDate, 10);
//save row data for text file
dataOutput = (block1 + block2 + issueAmt + STDOffsetAmount + RECOffsetAmount + RECOffsetOcc + RECOffsetExecuted +
block3 + issueAge + block4 + reinsPreNotice + reinsCeded + allPmts + YTDPmts + lName + fName +
block5 + ceded + WP + reportedDate);
//Write to the output record DI_Extract.txt
sw.WriteLine(dataOutput);
counter++;
pbrRecordsProcessed.Value = counter;
}//end for loop
}//end streamwriter
}//end if

After looking deeper into the code I realized that the connection was trying to open 3 times before it closed. Not sure why I was not getting exceptions all the time but correcting this issue not only sped up the application tremendously it cleared the exception.

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;