Opening a file with multiple objects - c#

I'm trying to open and display a file that has multiple objects in it (array). I am able to open a file and display only the first object inside the file, but I want to be able to open and display all the object inside the file.
Here is how I tried it:
public T BinaryFileDeSerialize<T>(string filePath)
{
FileStream fileStream = null;
Object obj;
try
{
if (!File.Exists(filePath))
throw new FileNotFoundException("The file" + " was not found. ", filePath);
fileStream = new FileStream(filePath, FileMode.Open);
BinaryFormatter b = new BinaryFormatter(); obj = b.Deserialize(fileStream);
}
catch
{
throw;
}
finally
{
if (fileStream != null)
fileStream.Close();
}
return (T)obj;
}
MainForm:
private Animal ReadFile(string filename)
{
BinSerializerUtility BinSerial = new BinSerializerUtility();
Animal str = BinSerial.BinaryFileDeSerialize<Animal>(filename);
return str;
}
private void mnuFileOpen_Click(object sender, EventArgs e)
{
if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
string thefilename = openFileDialog1.FileName;
Animal msg = ReadFile(thefilename);
if (msg != null)
{
Resultlst.Items.Add(msg);
}
else
UpdateResults();
}
}
I'm not getting any error. The problem is that it opens and display only the first object in the file. I want it to open and display all the objects in that file.
UPDATE:
This is how I Serialized it:
public void BinaryFileSerialize(object[] objs, string filePath)
{
FileStream fileStream = null;
try
{
fileStream = new FileStream(filePath, FileMode.Create);
BinaryFormatter b = new BinaryFormatter();
foreach (var obj in objs)
{
b.Serialize(fileStream, obj);
}
}
catch
{
throw;
}
finally
{
if (fileStream != null)
fileStream.Close();
}
}
UPDATE 2:
public T BinaryFileDeSerialize<T>(string filePath)
{
FileStream fileStream = null;
Object obj;
if (!File.Exists(filePath))
throw new FileNotFoundException("The file" + " was not found. ", filePath);
using (var thefileStream = new FileStream(filePath, FileMode.Open))
{
BinaryFormatter b = new BinaryFormatter();
obj = b.Deserialize(thefileStream);
}
return (T)obj;
}
private Animal[] ReadFile(string filename)
{
BinSerializerUtility BinSerial = new BinSerializerUtility();
var animals = BinSerial.BinaryFileDeSerialize<Animal[]>(filename);
return animals;
}
private void mnuFileOpen_Click(object sender, EventArgs e)
{
if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
string thefilename = openFileDialog1.FileName;
Animal []msg = ReadFile(thefilename);
if (msg != null)
{
Resultlst.Items.Add(msg);
}
else
UpdateResults();
}
I'm getting error:
Failed to convert an object of type Namespace.Animal to type
System.Collections.Generic.List`1 [Namespace.Animal].
The error comes from this return (T)obj;


If you want to use the current serializer you should change deserialize methos as follow:
public IList<T> BinaryFileDeSerialize<T>(string filePath) where T: class
{
var list = new List<T>();
if (!File.Exists(filePath))
throw new FileNotFoundException("The file" + " was not found. ", filePath);
using(var fileStream = new FileStream(filePath, FileMode.Open))
{
BinaryFormatter b = new BinaryFormatter();
while(fileStream.Position < fileStream.Length)
list.Add((T)b.Deserialize(fileStream));
}
return list;
}
And ReadFile should be like this:
private Animal[] ReadFile(string filename)
{
BinSerializerUtility BinSerial = new BinSerializerUtility();
var animals = BinSerial.BinaryFileDeSerialize<Animal>(filename);
return animals.ToArray();
}
private void mnuFileOpen_Click(object sender, EventArgs e)
{
if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
string thefilename = openFileDialog1.FileName;
var messages = ReadFile(thefilename);
if (messages != null)
{
messages.ToList().ForEach(msg =>
Resultlst.Items.Add(msg));
}
else
{
UpdateResults();
}
}
}


Silly question, but what happens if you serialize as List<Animal> then try to call BinaryFileDeSerialize<List<Animal>>()?
Also, you can simplify your method thusly with a using statement.
public T BinaryFileDeSerialize<T>(string filePath)
{
FileStream fileStream = null;
Object obj;
if (!File.Exists(filePath))
throw new FileNotFoundException("The file" + " was not found. ", filePath);
using(var fileStream = new FileStream(filePath, FileMode.Open))
{
BinaryFormatter b = new BinaryFormatter();
obj = b.Deserialize(fileStream);
}
return (T)obj;
}
EDIT:
Try these tweaks to your code...
//call via BinaryFileSerialize<Animal>(..., ...);
public void BinaryFileSerialize<T>(T[] objs, string filePath)
{
using(var fileStream = new FileStream(filePath, FileMode.Create))
{
BinaryFormatter b = new BinaryFormatter();
b.Serialize(fileStream, objs);
}
}
private Animal[] ReadFile(string filename)
{
BinSerializerUtility BinSerial = new BinSerializerUtility();
var animals = BinSerial.BinaryFileDeSerialize<Animal[]>(filename);
return animals;
}

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catch (Exception ex)
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//var access = AppViewModel.GetAccessor();
//byte[] bytes = Encoding.ASCII.GetBytes(jsonString);
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mutex.ReleaseMutex();
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I did try the following:
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{
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MemoryStream memStream = null;
try
{
memStream = new MemoryStream();
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binFormatter.Serialize(memStream, obj);
memStream.Seek(0, 0); //set position at 0,0
serializedObject = memStream.ToArray();
}
finally
{
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}
return serializedObject; // return the array.
}
But the problem with it is that I don't know where to insert the fileName (The path)

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b.Serialize(fileStream, obj);
}
SaveToFile function:
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//Animal array
Animal [] animals = new Animal[animalmgr.Count];
for (int index = 0; index < animalmgr.Count; index++)
{
animals[index] = animalmgr.GetAt(index);
}
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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,
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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))
{
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return Encoding.UTF8.GetString(mso.ToArray());
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}
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{
public static string Serialize(T options, string path)
{
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{
File.Delete(path);
}
catch (Exception)
{
}
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{
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{
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catch (Exception ex)
{
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return xml;
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public static T Deserialize(string path)
{
T filteroptions;
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{
var bf = new BinaryFormatter();
filteroptions = (T)bf.Deserialize(fs);
}
return filteroptions;
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Use this code:
public static FilterOptions Deserialize(string serializedData)
{
try
{
var xmlSerializer = new XmlSerializer(typeof(FilterOptions));
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var collection = (FilterOptions)xmlSerializer.Deserialize(xmlReader);
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catch (Exception)
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return new FilterOptions();
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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

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