Develop Reference

Foreach not completing iterations

C# Foreach not completing iterations: if I have 10 XML records it only creates about 6 XML files.
public void PRODUCT()
{
try
{
var toProdSignlCRMList = _db.kv_sp_Product().ToList();
if (toProdSignlCRMList.Count > 0)
{
foreach (kv_sp_Product_Result myProdSignalLoop in toProdSignlCRMList)
{
var erp_prod_signal = new erp_crm_class.PRODUCT
{
CODE = myProdSignalLoop.Code.ToString().Trim(),
SHORTDESC = myProdSignalLoop.Description_1.ToString().Trim(),
INTERNATIONAL = false,
};
XmlSerializer xsSubmit = new XmlSerializer(typeof(erp_crm_class.PRODUCT));
var ProdSignalxml = "";
using (var sww = new StringWriter())
{
using (XmlWriter writer = XmlWriter.Create(sww))
{
xsSubmit.Serialize(writer, erp_prod_signal);
ProdSignalxml = sww.ToString();
using (StreamWriter outputFile = new StreamWriter(Convert.ToString("C:\\Upload\\" + "PRODUCT" + DateTime.Now.ToString("yyyyMMddhhmmssfff") + ".xml")))
{
outputFile.Write(ProdSignalxml);
}
}
}
}
}
}
catch (Exception ex)
{
}
}

You are using a Try/Catch block.
A Try/Catch block exits the Try block any time the code fails, and immediately runs the Catch block.
Normally you'd have some sort of error-handling in the catch block but for debugging you could also add the following to help you find out what is going on:
catch(Exception ex)
{
MessageBox.Show(ex.Message, "Error");
}
If the actual message doesn't contain any useful information, another way to go about is stepping through each loop and see what part fails and why.
Third option and most likely the best one is to remove your Try/Catch block and make sure you are using a debugger that is configured to break at exceptions - this way you get the actual error in your debugger.

Anonymous Pipe not ending stream?

Hello I am having a strange error with using pipes to communicate between two process. In short everything is working fine with the program except that the client side never closes the stream, meaning the server's streamReader.readLine never returns null, causing the sever process to never terminate. I'm convinced this is a simple issue but I and struggling to find a answer. Here is some relevant code:
Server Side:
using (StreamReader sr = new StreamReader(clientServer))
{
// Display the read text to the console
string temp;
int count = 0;
while ((temp = sr.ReadLine()) != null)
{
if (count == 0)
{
Console.WriteLine("==========Parent Process found text:like==========");
}
Console.WriteLine(temp);
count++;
}
Console.WriteLine("out of while loop");
}
Client Project:
using System;
using System.Collections.Generic;
using System.IO;
using System.IO.Pipes;
class PipeClient
{
static void Main(string[] args)
{
try
{
if (args.Length < 3)
{
Console.WriteLine("Invalid number of commandline arguments");
}
else
{
List<string> inputList = new List<string>();
List<string> foundMatchList = new List<string>();
using (PipeStream pipeClientIn =
new AnonymousPipeClientStream(PipeDirection.In, args[0]))
{
using (StreamReader sr = new StreamReader(pipeClientIn))
{
// Display the read text to the console
string temp;
int count = 0;
while ((temp = sr.ReadLine()) != null)
{
if (count == 0)
{
Console.WriteLine("==========Client Process Read Text:==========");
}
Console.WriteLine(temp);
inputList.Add(temp);
count++;
}
foreach (var curtString in inputList)
{
if (curtString.Contains(args[2]))
{
foundMatchList.Add(curtString);
}
}
}
//Console.WriteLine("released sr");
}
// Console.WriteLine("released pipeClientIn");
using (PipeStream pipeClientOut =
new AnonymousPipeClientStream(PipeDirection.Out, args[1]))
{
using (StreamWriter sw = new StreamWriter(pipeClientOut))
{
sw.AutoFlush = true;
foreach (var match in foundMatchList)
{
sw.WriteLine(match);
}
}
}
//Console.WriteLine("released pipeClientOut");
}
}
catch (Exception e)
{
/* if (args.Length == 0)
Console.WriteLine("no arguments");
foreach(String s in args)
{
Console.Write("{0} ", s);
}*/
Console.WriteLine(e.Message);
}
}
}
I've tested and can confirm that the client process terminates.
I attempted to manually flush and close the Client StreamWriter but this did not work.
My overall question is: Why am I never seeing the the "out of while loop" message? And how can fix my client so that it will end the stream?

Did you call clientServer.DisposeLocalCopyOfClientHandle()?
from msdn
The DisposeLocalCopyOfClientHandle method should be called after the
client handle has been passed to the client. If this method is not
called, the AnonymousPipeServerStream object will not receive notice
when the client disposes of its PipeStream object.
hope this helps

How to fix a boolean method that returns true everytime asp.net

I designed my webpage to read a data string then display the results on labels in an html table. I am attempting to highlight the row that my database reads as a current order. My only problem is only one record is set to be active but they all highlight as if they were active. I use an array to set my data and I also use the label to get the ID I need (all is in code below). I have posted my method and where I use it in the asp page load. How can I fix my method to return correctly?
The implementing of the method in page load
if (lineData.IsCurrentOrderFind(L68.Text))
{
myTable.Rows[1].Cells[0].BgColor = "#FE2E2E";
myTable.Rows[1].Cells[1].BgColor = "#FE2E2E";
myTable.Rows[1].Cells[2].BgColor = "#FE2E2E";
myTable.Rows[1].Cells[3].BgColor = "#FE2E2E";
myTable.Rows[1].Cells[4].BgColor = "#FE2E2E";
}
Here is method that label above gets passed to
public bool IsCurrentOrderFind(string itemNumber)
{
StringBuilder sqlString = new StringBuilder();
sqlString.Append("SELECT * ");
sqlString.Append("FROM WorkOrder ");
sqlString.Append("WHERE LineNumber = " + ConfigurationManager.AppSettings["Line"] + " AND LineCompleted = 0 AND (ScaleGroup LIKE '%1' OR ScaleGroup LIKE '%3') ");
sqlString.Append(" AND CaseGenNum6 = #CaseGenNum6");
SqlDataReader reader = null;
SqlConnection dbConn = App_Code.DBHelper.getConnection();
SqlParameter[] parameters = new SqlParameter[] { new SqlParameter("#CaseGenNum6", itemNumber) };
try
{
reader = App_Code.DBHelper.executeQuery(dbConn, sqlString.ToString(), parameters);
while (reader.Read())
{
IsCurrentOrder = (reader["IsCurrentOrder"] != DBNull.Value && !string.IsNullOrEmpty(reader["IsCurrentOrder"].ToString())) ? true : false;
}
reader.Close();
reader.Dispose();
dbConn.Close();
dbConn.Dispose();
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (dbConn != null)
{
try { dbConn.Close(); dbConn.Dispose(); }
catch { }
}
if (reader != null)
{
try { reader.Close(); reader.Dispose(); }
catch { }
}
}
if (IsCurrentOrder == true) I realize this is not necessary
{
return true;
}
else
{
return false;
}
}

The problem could be with this expression:
!string.IsNullOrEmpty(reader["IsCurrentOrder"].ToString())
Instead of calling ToString(), try simply casting it to a string:
!string.IsNullOrEmpty((string)reader["IsCurrentOrder"])
Possibly even better (the previous line might throw an exception if it's not really a string):
!string.IsNullOrEmpty(reader["IsCurrentOrder"] as string)
The reason being is that if the string is really null, calling ToString() will return a non-null string "null".

IsCurrentOrder is not declared locally. It seems to be declared at a higher scope. When you enter this function, nothing is initializing the variable (back to false). So, it is remaining at its last setting. Try this code instead:
public bool IsCurrentOrderFind(string itemNumber)
{
bool IsCurrentOrder = false;
//and the rest of your source code

the line
IsCurrentOrder = (reader["IsCurrentOrder"] != DBNull.Value && !string.IsNullOrEmpty(reader["IsCurrentOrder"].ToString())) ? true : false;
}
It's not actually checking the value of the field, only that it's not null or empty.
Try
if(
(reader["IsCurrentOrder"] != DBNull.Value
&&
!string.IsNullOrEmpty(reader["IsCurrentOrder"].ToString()))
)
{
IsCurrentOrder = reader["IsCurrentOrder"];
}
else
IsCurrentOrder = false;
I think there is a lot of refactoring you could do to this method though that will simplify the logic.

Trying to deserialize more than 1 object at the same time

Im trying to send some object from a server to the client.
My problem is that when im sending only 1 object, everything works correctly. But at the moment i add another object an exception is thrown - "binary stream does not contain a valid binaryheader" or "No map for object (random number)".
My thoughts are that the deserialization does not understand where the stream starts / ends and i hoped that you guys can help me out here.
heres my deserialization code:
public void Listen()
{
try
{
bool offline = true;
Dispatcher.Invoke(System.Windows.Threading.DispatcherPriority.Normal,
new Action(() => offline = Offline));
while (!offline)
{
TcpObject tcpObject = new TcpObject();
IFormatter formatter = new BinaryFormatter();
tcpObject = (TcpObject)formatter.Deserialize(serverStream);
if (tcpObject.Command == Command.Transfer)
{
SentAntenna sentAntenna = (SentAntenna)tcpObject.Object;
int idx = 0;
foreach (string name in SharedProperties.AntennaNames)
{
if (name == sentAntenna.Name)
break;
idx++;
}
if (idx < 9)
{
PointCollection pointCollection = new PointCollection();
foreach (Frequency f in sentAntenna.Frequencies)
pointCollection.Add(new Point(f.Channel, f.Intensity));
SharedProperties.AntennaPoints[idx] = pointCollection;
}
}
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message); // raise an event
}
}
serialization code:
case Command.Transfer:
Console.WriteLine("Transfering");
Thread transfer = new Thread(new ThreadStart(delegate
{
try
{
string aName = tcpObject.Object.ToString();
int indx = 0;
foreach (string name in names)
{
if (name == aName)
break;
indx++;
}
if (indx < 9)
{
while (true) // need to kill when the father thread terminates
{
if (antennas[indx].Frequencies != null)
{
lock (antennas[indx].Frequencies)
{
TcpObject sendTcpObject = new TcpObject();
sendTcpObject.Command = Command.Transfer;
SentAntenna sa = new SentAntenna(antennas[indx].Frequencies, aName);
sendTcpObject.Object = sa;
formatter.Serialize(networkStream, sendTcpObject);
}
}
}
}
}
catch (Exception ex) { Console.WriteLine(ex); }
}));
transfer.Start();
break;

Interesting. There's nothing particularly odd in your serialization code, and I've seen people use vanilla concatenation for multiple objects in the past, although I've actually always advised against it as BinaryFormatter does not explicitly claim this scenario is OK. But: if it isn't, the only thing I can suggest is to implement your own framing; so your write code becomes:
serialize to an empty MemoryStream
note the length and write the length to the NetworkStream, for example as a simple fixed-width 32-bit network-byte-order integer
write the payload from the MemoryStream to the NetworkStream
rinse, repeat
And the read code becomes:
read exactly 4 bytes and compute the length
buffer that many bytes into a MemoryStream
deserialize from the NetworkStream
(Noting in both cases to set the MemoryStream's position back to 0 between write and read)
You can also implement a Stream-subclass that caps the length if you want to avoid a buffer when reading, bit that is more complex.

apperantly i came up with a really simple solution. I just made sure only 1 thread is allowed to transfer data at the same time so i changed this line of code:
formatter.Serialize(networkStream, sendTcpObject);
to these lines of code:
if (!transfering) // making sure only 1 thread is transfering data
{
transfering = true;
formatter.Serialize(networkStream, sendTcpObject);
transfering = false;
}

Advance C# ReadLine() to next line in a function call

In my C# app I'm trying to feed into ReadLine() a simple text document with 7 digit strings separated line by line. What I'm attempting to do is grab the next 7 digit string each time the function is called. Here's what I have so far:
string invoiceNumberFunc()
{
string path = #"C:\Users\sam\Documents\GCProg\testReadFile.txt";
try
{
using (StreamReader sr = new StreamReader(path))
{
invoiceNumber = sr.ReadLine();
}
}
catch (Exception exp)
{
Console.WriteLine("The process failed: {0}", exp.ToString());
}
return invoiceNumber;
}
How do I advance to the next line each time the invoiceNumberFunc() is called?
Thanks in advance.

You'd need to keep hold of the StreamReader between calls, either passing it into the method as a new parameter or making it a member variable of the class.
Personally I prefer the idea of it becoming a parameter, so that it never ends up as a member variable - that makes the life-time easier to manage:
void DoStuff()
{
string path = #"C:\Users\sam\Documents\GCProg\testReadFile.txt";
using (StreamReader sr = new StreamReader(path))
{
while (keepGoing) // Whatever logic you have
{
string invoice = InvoiceNumberFunc(sr);
// Use invoice
}
}
}
string InvoiceNumberFunc(TextReader reader)
{
string invoiceNumber;
try
{
invoiceNumber = reader.ReadLine();
}
catch (Exception exp)
{
Console.WriteLine("The process failed: {0}", exp.ToString());
}
return invoiceNumber;
}

You can't, since you create and dispose the stream reader in the function. Two ways come to mind:
You could store the stream reader in a member variable, or read all at once and store an array in a member variable.
Or you make it an iterator method by changing the return type to IEnumerable<string>, and changing the part in the using block to:
while ((invoiceNumber = sr.ReadLine()) != null) {
yield return invoiceNumber;
}
This way, you can call foreach on your invoiceNumberFunc.

You need to use the same StreamReader rather than creating a new one. Each time you create a new one and dispose of the old one you're starting right back at the start of the file.
Try passing the same StreamReader reference in or keeping a record of the position you are at in the stream and using Seek() on the base stream if necessary. I'd recommend the first of these personally.

You need to rework this, so that you're not creating the streamreader inside the method, but rather creating it at the class level, and just using it in the method, then disposing/closing the reader when you are done. Something like:
class MyClass
{
private StreamReader sr;
string invoiceNumberFunc()
{
if (sr == null)
sr = new StreamReader(path);
if (sr.EndOfStream) {
sr.Close();
sr = null;
return string.Empty;
}
try {
return sr.ReadLine();
}
catch(Exception exp) {
Console.WriteLine("Process failed {0}",exp.ToString());
return string.Empty;
}
}
}
In this case, it might also be a good idea to make your class IDisposable so you can verify that the StreamReader gets disposed, and also potentially make "initialize"/"close" routines, instead of doing the initialize and shutdown how I did here.

What you are looking for is the yield command:-
IEnumerable<string> GetInvoiceNumbers()
{
string path = #"C:\Users\sam\Documents\GCProg\testReadFile.txt";
using (StreamReader sr = new StreamReader(path))
{
while (!sr.EndOfStream)
{
yield return sr.ReadLine();
}
}
}
Now you can consume the return of this function with a simple for each:-
foreach(string invoiceNumber in GetInvoiceNumbers())
{
//Do Stuff with invoice number
}
Or get creative with LINQ.

An other way of doing this is to transform your function in an iterator block using the yield return statement
The only thing is to make sure you add a finaly clause to your try and remove the catch as the yield return cannot be used in a naked try / catch. So your code would become:
IEnumerable<String> invoiceNumberFunc()
{
string path = #"C:\Users\sam\Documents\GCProg\testReadFile.txt";
try
{
using ( System.IO.StreamReader sr = new System.IO.StreamReader( path ) )
{
String invoiceNumber;
while ( ( invoiceNumber = sr.ReadLine() ) != null )
{
yield return sr.ReadLine();
}
}
}
finally
{
}
}