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Cannot access a closed stream when passing stream to another function

I need to pass a stream to a couple of functions in another class, but its throwing an error
Cannot access a closed stream
Here's the code:
first method:
Here it opens a file with File.Open method and then creates a memorystream object and it copies FileStream to MemoryStream. then sets Position to 0 (i set position to 0, because i was that in a solution, but not helping tho). Then it creates an object of class DocxConvert and call the Converto method by passing MemoryStream to it.
using (var stream = File.Open(tempPath2, FileMode.Open))
{
using(var ms = new MemoryStream())
{
stream.CopyTo(ms);
ms.Position = 0;
using (var docx = new DocxConvert())
{
return docx.Converto(ms);
}
}
}
DocxConvert Class:
It takes stream and then calls copyStream method by passing the accepted stream.
copyStream method in DocxConvert Class: it should copy the accepted stream to another stream called _memoryStream which is a class property.
public class DocxConvert
{
private MemoryStream _memoryStream = new MemoryStream();
public bool Converto(Stream stream)
{
try
{
copyStream(stream);
//more code
}
catch (IOException ex)
{
Debug.WriteLine(ex);
}
return true;
}
private void copyStream(Stream stream)
{
stream.CopyTo(_memoryStream); //here it throws the error
}
}
p.s. I search for this error here before posting, but non of the topics helped me.
SOLVED by restarting PC, the code it ok.

I am not aware about your question .But here in the code bellow no excepion
private void button1_Click(object sender, EventArgs e)
{
string tempPath2 = Application.StartupPath + "//" + "test.txt";
using (var stream = File.Open(tempPath2, FileMode.Open))
{
using (var ms = new MemoryStream())
{
stream.CopyTo(ms);
ms.Position = 0;
var docx = new DocxConvert();
var isok = docx.Converto(ms);
}
}
}
The bellow is the calss defined where _memorystream is defined at top
MemoryStream _memoryStream = new MemoryStream();
public bool Converto(Stream stream)
{
try
{
copyStream(stream);
//more code
}
catch (IOException ex)
{
// Debug.WriteLine(ex);
}
return true;
}
private void copyStream(Stream stream)
{
try
{
stream.CopyTo(_memoryStream);
}
catch (Exception)
{
}
}

Using FileStream to write to a file first time after the file is created gives an exception

I am trying to write some json text. But I get an Exception like
The process cannot access the file C:\blah blah\SystemInActivity.json because it is being used by an other process. But then second time when I run the app after json file is created and then when I write I dont get an exception. Please help.
class ApplicationSettingsViewModel
{
ApplicationSettingsModel model;
MemoryMappedFile mmf = null;
public string FullPath = string.Empty;
//This is not a singleton class but I guess it has to be one but its ok for demonstration.
public ApplicationSettingsViewModel()
{
model = new ApplicationSettingsModel();
CreateFileWithoutMemoryMap();
//MemoryMapped();
}
public string GetDriectory()
{
return Path.GetDirectoryName(FullPath);
}
private void CreateFileWithoutMemoryMap()
{
var info = Directory.CreateDirectory(Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData) + "/" + model.Data.Settings.OrcaUISpecificSettings.TimeOutFolder);
string path = Path.Combine(info.FullName + #"\" + model.Data.Settings.OrcaUISpecificSettings.File);
//mmf = MemoryMappedFile.CreateFromFile(path, FileMode.CreateNew, "MyMemoryFile", 1024 * 1024, MemoryMappedFileAccess.ReadWrite);
FullPath = path;
if (!File.Exists(path))
{
File.Create(path);
}
}
public void WriteToFile(string json)
{
try
{
FileStream fileStream = File.Open(FullPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite); //This line giving Exception
fileStream.SetLength(0);
fileStream.Close(); // This flushes the content, too.
using (StreamWriter sw = new StreamWriter(FullPath))
{
sw.Write(json);
}
}
catch (Exception ex)
{
}
}
In the constructor of the MainWindow I am calling the write method
private ApplicationSettingsViewModel AppViewModel;
public MainWindow()
{
InitializeComponent();
//MessageBox.Show("App Started");
AppViewModel = new ApplicationSettingsViewModel();
WriteToFile("Active");
}
public void WriteToFile(string status)
{
var root = new Root();
string jsonString = string.Empty;
root.AllApplications.Add(new DataToWrite() { AppName = "DevOrca", Status = status });
try
{
jsonString = JsonConvert.SerializeObject(root, Formatting.Indented);
}
catch (Exception ex)
{
MessageBox.Show(jsonString);
MessageBox.Show("Exception");
}
mutex.WaitOne();
//Serialize Contents and write
AppViewModel.WriteToFile(jsonString);
//var access = AppViewModel.GetAccessor();
//byte[] bytes = Encoding.ASCII.GetBytes(jsonString);
//access.Write(bytes, 0, bytes.Length);
mutex.ReleaseMutex();
}

File.Create() method opens FileStream to create a file and you need to close it, something like this:
File.Create(path).Close();

Isolated Storage - How to read the appended data

I have a Game application(WP8), where we are saving the scores of multiple attampts and showing it to user.
I have a Object with fields noOfStonesPicked and noOfFruitsPicked.
Here is my code:
MyTopic topicObj = new MyTopic ();
for (int i = 0; i <= 2; i++)
{
Test mt = new Test();
mt.noOfStonesPicked = 12;
mt.noOfFruitsPicked= 20;
topicObj.Stats.Add(mt);
}
WritetestTopicState(topicObj);
Now 3 attempts with each one having noOfStonesPicked -12 and noOfFruitsPicked - 20
Now i have saving this like :
public static void WritetestTopicState(MyTopic topic)
{
try
{
using (var store = IsolatedStorageFile.GetUserStoreForApplication())
{
using (StreamWriter sw = new StreamWriter(store.OpenFile("12.xml", FileMode.Append, FileAccess.Write)))
{
XmlSerializer serializer = new XmlSerializer(typeof(MyTopic));
serializer.Serialize(sw, topic);
serializer = null;
}
}
}
catch (Exception)
{
throw;
}
}
Now how can i retrive these values and display ?
EDIT
This is what i have tried:
public static MyTopic ReadMockTestTopicState()
{
MyTopic topic = null;
try
{
using (IsolatedStorageFile isoStore = IsolatedStorageFile.GetUserStoreForApplication())
{
// Read application settings.
if (isoStore.FileExists("11.xml"))
{
using (var store = IsolatedStorageFile.GetUserStoreForApplication())
{
using (StreamReader SR = new StreamReader(store.OpenFile("12.xml", FileMode.Open, FileAccess.Read)))
{
XmlSerializer serializer = new XmlSerializer(typeof(MyTopic));
topic = (MyTopic)serializer.Deserialize(SR);
serializer = null;
}
}
}
else
{
// If setting does not exists return default setting.
topic = new MyTopic();
}
}
}
catch (Exception)
{
throw;
}
return topic;
}

XmlSerializer serializer = new XmlSerializer(typeof(MyTopic));
StreamReader reader = new StreamReader(path);
_myTopic = (MyTopic)serializer.Deserialize(reader);
reader.Close();
This should be enough for deserializing, If your MyTopic object is properly serializable, I mean if properties of the MyTopic object are properly attributed for xml serialization.

Read\write to a file: heavily used application

I had asked a question here: The process cannot access the file because it is being used by another process: Correct way to read\write to a file: heavily used application-Part II.
We have a heavily used .Net 3.5 application that reads "expensive to create" data and caches it. However we are getting a lot of errors around both reading the cache file and writing to the cache file. I have a single process, multiple threads and I want the application to synchronize access to a resource. I was advised to use a simple locking mechanism like lock or ReaderWriterLockSlim (see: http://msdn.microsoft.com/en-us/library/system.threading.readerwriterlockslim.aspx). This however seems to have made the problem much much worse in production.
EDIT
After the change was implemented, a lot of the cache files have a ">" tag in the end. Due to this the files are no longer xml files.
Can someone look at the code and advise what could I be doing wrong?
Code before change:
private XmlDocument ReadFromFile()
{
XmlDocument result=null;
string fileSystemPath=FileSystemPath();
try
{
result=new XmlDocument();
using (StreamReader streamReader = new StreamReader(fileSystemPath))
{
result.Load(streamReader);
}
}
catch (FileNotFoundException)
{
result=null;
}
return result;
}
private object thisObject= new object();
private void WriteToFile(string siteID, XmlDocument stuff)
{
string fileSystemPath=FileSystemPath();
lock(thisObject)
{
using (StreamWriter streamWriter = new StreamWriter(fileSystemPath))
{
stuff.Save(streamWriter);
}
}
}
Code after change:
private readonly ReaderWriterLockSlim readerWriterLockSlim = new ReaderWriterLockSlim();
private XmlDocument ReadFromFile()
{
XmlDocument result = null;
var fileSystemPath = FileSystemPath();
readerWriterLockSlim.EnterReadLock();
try
{
result = new XmlDocument();
using (var fileStream = new FileStream(fileSystemPath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
using (var streamReader = new StreamReader(fileStream))
{
result.Load(streamReader);
}
}
catch (FileNotFoundException)
{
result = null;
}
finally
{
readerWriterLockSlim.ExitReadLock();
}
return result;
}
private void WriteToFile()
{
var fileSystemPath = FileSystemPath();
readerWriterLockSlim.EnterWriteLock();
try
{
using (var fileStream = new FileStream(fileSystemPath, FileMode.OpenOrCreate, FileAccess.Write, FileShare.ReadWrite))
using (var streamWriter = new StreamWriter(fileStream))
{
stuff.Save(streamWriter);
}
}
finally
{
readerWriterLockSlim.ExitWriteLock();
}
}

This code with some little changes should work
private readonly ReaderWriterLockSlim readerWriterLockSlim = new ReaderWriterLockSlim();
private XmlDocument ReadFromFile()
{
XmlDocument result = null;
var fileSystemPath = FileSystemPath();
readerWriterLockSlim.EnterReadLock();
try
{
result = new XmlDocument();
using (var streamReader = new StreamReader(fileStream))
{
result.Load(streamReader);
}
}
catch (FileNotFoundException)
{
result = null;
}
finally
{
readerWriterLockSlim.ExitReadLock();
}
return result;
}
private void WriteToFile(XmlDocument stuff)
{
var fileSystemPath = FileSystemPath();
readerWriterLockSlim.EnterWriteLock();
try
{
using (var streamWriter = new StreamWriter(fileSystemPath))
{
stuff.Save(streamWriter);
}
}
finally
{
readerWriterLockSlim.ExitWriteLock();
}
}

How to keep XmlSerializer from killing NewLines in Strings?

Suppose I have a simple Class with just one Member a String.
public class Abc
{
private String text;
public String Text
{
get { return this.text; }
set { this.text = value; }
}
}
Now when I serialize and then deserialize it with the questionable XmlSerializer any text containing newlines ('\r\n' or Environment.NewLine) are transformed to '\n'.
How do I keep the newlines?

It is not the XmlSerializer but the XmlWriter which is removing your CR. To retain it we must have the writer convert CR to its character entity 
.
XmlWriterSettings ws = new XmlWriterSettings();
ws.NewLineHandling = NewLineHandling.Entitize;
XmlSerializer ser = new XmlSerializer( typeof( Abc ) );
using (XmlWriter wr = XmlWriter.Create( "abc.xml", ws )) {
ser.Serialize( wr, s );
}
This is exactly the same with DataContractSerializer:
var ser = new DataContractSerializer( typeof( Abc ) );
using (XmlWriter wr = XmlWriter.Create( "abc.xml", ws )) {
ser.Serialize( wr, s );
}
Why do we need to do this?
This is because compliant XML parsers must, before parsing, translate CRLF and any CR not followed by a LF to a single LF. This behavior is defined in the End-of-Line handling section of the XML 1.0 specification.
As this happens before parsing, you need to encode CR as its character entity if you want the CR to exist in the document.

public class SerializeAny<TF> where TF : new()
{
public static TF Deserialize(string serializedData)
{
try
{
var xmlSerializer = new XmlSerializer(typeof(TF));
TF collection;
using (var xmlReader = new XmlTextReader(serializedData, XmlNodeType.Document, null))
{
collection = (TF)xmlSerializer.Deserialize(xmlReader);
}
return collection;
}
catch (Exception)
{
}
return new TF();
}
public static TF DeserializeZip(string path)
{
try
{
var bytes = File.ReadAllBytes(path);
string serializedData = Unzip(bytes);
TF collection = Deserialize(serializedData);
return collection;
}
catch (Exception)
{
}
return new TF();
}
public static string Serialize(TF options)
{
var xml = "";
try
{
var xmlSerializer = new XmlSerializer(typeof(TF));
using (var stringWriter = new StringWriter())
{
xmlSerializer.Serialize(stringWriter, options);
xml = stringWriter.ToString();
}
}
catch (Exception ex)
{
return ex.Message;
}
return xml;
}
public static string SerializeZip(TF options, string path)
{
var xml = "";
try
{
xml = Serialize(options);
var zip = Zip(xml);
File.WriteAllBytes(path, zip);
}
catch (Exception ex)
{
return ex.Message;
}
return xml;
}
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2202:Do not dispose objects multiple times")]
internal static String SerializeObject<T>(T obj, Encoding enc)
{
using (var ms = new MemoryStream())
{
var xmlWriterSettings = new System.Xml.XmlWriterSettings()
{
// If set to true XmlWriter would close MemoryStream automatically and using would then do double dispose
// Code analysis does not understand that. That's why there is a suppress message.
CloseOutput = false,
Encoding = enc,
OmitXmlDeclaration = false,
Indent = true
};
using (var xw = XmlWriter.Create(ms, xmlWriterSettings))
{
var s = new XmlSerializer(typeof(T));
s.Serialize(xw, obj);
}
return enc.GetString(ms.ToArray());
}
}
private static void CopyTo(Stream src, Stream dest)
{
byte[] bytes = new byte[4096];
int cnt;
while ((cnt = src.Read(bytes, 0, bytes.Length)) != 0)
{
dest.Write(bytes, 0, cnt);
}
}
private static byte[] Zip(string str)
{
var bytes = Encoding.UTF8.GetBytes(str);
using (var msi = new MemoryStream(bytes))
using (var mso = new MemoryStream())
{
using (var gs = new GZipStream(mso, CompressionMode.Compress))
{
//msi.CopyTo(gs);
CopyTo(msi, gs);
}
return mso.ToArray();
}
}
private static string Unzip(byte[] bytes)
{
using (var msi = new MemoryStream(bytes))
using (var mso = new MemoryStream())
{
using (var gs = new GZipStream(msi, CompressionMode.Decompress))
{
CopyTo(gs, mso);
}
return Encoding.UTF8.GetString(mso.ToArray());
}
}
}

public class BinarySerialize<T> where T : new()
{
public static string Serialize(T options, string path)
{
var xml = "";
try
{
File.Delete(path);
}
catch (Exception)
{
}
try
{
using (var fs = new FileStream(path, FileMode.Create, FileAccess.Write, FileShare.ReadWrite))
{
var bf = new BinaryFormatter();
bf.Serialize(fs, options);
}
}
catch (Exception ex)
{
return ex.Message;
}
return xml;
}
public static T Deserialize(string path)
{
T filteroptions;
using (var fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read))
{
var bf = new BinaryFormatter();
filteroptions = (T)bf.Deserialize(fs);
}
return filteroptions;
}
}

Use this code:
public static FilterOptions Deserialize(string serializedData)
{
try
{
var xmlSerializer = new XmlSerializer(typeof(FilterOptions));
var xmlReader = new XmlTextReader(serializedData,XmlNodeType.Document,null);
var collection = (FilterOptions)xmlSerializer.Deserialize(xmlReader);
return collection;
}
catch (Exception)
{
}
return new FilterOptions();
}

Nice solution, Lachlan Roche!
The function below (in VB.NET) uses a StringWriter to return a String, rather than writing the result to a file using an XmlWriter.
''' <summary>
''' Exports the object data to an XML formatted string.
''' Maintains CR characters after deserialization.
''' The object must be serializable to work.
''' </summary>
Public Function ExportObjectXml(ByVal obj As Object) As String
If obj Is Nothing Then
Return String.Empty
End If
Dim serializer As New XmlSerializer(obj.GetType)
Dim settings As New XmlWriterSettings With {.NewLineHandling = NewLineHandling.Entitize}
Using output As New StringWriter
Using writer As XmlWriter = XmlWriter.Create(output, settings)
serializer.Serialize(writer, obj)
Return output.ToString
End Using
End Using
End Function