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how to save/load data to n xml file

i'm trying to load and save my data in my datagrid to an xml file using Singleton Design.
i have created
public class DataProvider
{
private static DataProvider singletonInstance = new DataProvider();
private ObservablePerson Person;
/// <summary>
/// Private constructor
/// </summary>
private DataProvider()
{
}
public static DataProvider GetInstance()
{
if (singletonInstance == null)
singletonInstance = new DataProvider();
return singletonInstance;
}
public bool SaveToXml(List<Person> PersonsList)
{
return false;
}
public List<Person> LoadFromX()
{
return new List<Person>() { new Person() { name= "jhon" } };
}
}
}
and this is the object i want to save
[Serializable]
public class ObservablePerson : ObservableObject
{
private string _name;
public string name
{
get
{
return _name;
}
set
{
_name= value;
NotifyPropertyChanged();}
and i also created a view model form from person.
what should i do to save those data in my datagrid in a xml file .
thanks.

Read an XML file using XmlTextReader and call Read method to read its node one by one until the end of file.
using System;
using System.Xml;
namespace ReadXml1 {
class Class1 {
static void Main(string[] args) {
// Create an isntance of XmlTextReader and call Read method to read the file
XmlTextReader textReader = new XmlTextReader("C:\\books.xml");
textReader.Read();
// If the node has value
while (textReader.Read()) {
// Move to fist element
textReader.MoveToElement();
Console.WriteLine("XmlTextReader Properties Test");
Console.WriteLine("===================");
// Read this element's properties and display them on console
Console.WriteLine("Name:" + textReader.Name);
Console.WriteLine("Base URI:" + textReader.BaseURI);
Console.WriteLine("Local Name:" + textReader.LocalName);
Console.WriteLine("Attribute Count:" + textReader.AttributeCount.ToString());
Console.WriteLine("Depth:" + textReader.Depth.ToString());
Console.WriteLine("Line Number:" + textReader.LineNumber.ToString());
Console.WriteLine("Node Type:" + textReader.NodeType.ToString());
Console.WriteLine("Attribute Count:" + textReader.Value.ToString());
}
}
}
}
and for creating and save to XML file:
using System;
using System.Xml;
namespace ReadingXML2 {
class Class1 {
static void Main(string[] args) {
// Create a new file in C:\\ dir
XmlTextWriter textWriter = new XmlTextWriter("C:\\myXmFile.xml", null);
// Opens the document
textWriter.WriteStartDocument();
// Write comments
textWriter.WriteComment("First Comment XmlTextWriter Sample Example");
textWriter.WriteComment("myXmlFile.xml in root dir");
// Write first element
textWriter.WriteStartElement("Student");
textWriter.WriteStartElement("r", "RECORD", "urn:record");
// Write next element
textWriter.WriteStartElement("Name", "");
textWriter.WriteString("Student");
textWriter.WriteEndElement();
// Write one more element
textWriter.WriteStartElement("Address", "");
textWriter.WriteString("Colony");
textWriter.WriteEndElement();
// WriteChars
char[] ch = new char[3];
ch[0] = 'a';
ch[1] = 'r';
ch[2] = 'c';
textWriter.WriteStartElement("Char");
textWriter.WriteChars(ch, 0, ch.Length);
textWriter.WriteEndElement();
// Ends the document.
textWriter.WriteEndDocument();
// close writer
textWriter.Close();
}
}
}

Let's use Xml and Xml.Serialization:
using System.Xml;
using System.Xml.Serialization;
On your singleton, implements
public static List<T> LoadFromXml<T>(string path, string fileName)
{
var xmlSerializer = new XmlSerializer(typeof(List<T>));
var xmlText = File.ReadAllText(Path.Combine(path, fileName));
return (List<T>)xmlSerializer.Deserialize(new StringReader(xmlText));
}
public static bool SaveToXml<T>(List<T> list, string path, string fileName)
{
var xmlText = Serialize<T>(list);
try
{
if (!Directory.Exists(path))
Directory.CreateDirectory(path);
File.WriteAllText(Path.Combine(path, fileName), xmlText);
return true;
}
catch(Exception e)
{
return false;
}
}
private static string Serialize<T>(List<T> list)
{
if (list == null || !list.Any())
return string.Empty;
var xmlSerializer = new XmlSerializer(typeof(List<T>));
using (var stringWriter = new StringWriter())
{
using (var xmlWriter = XmlWriter.Create(stringWriter, new XmlWriterSettings { Indent = true }))
{
xmlSerializer.Serialize(xmlWriter, list);
return stringWriter.ToString();
}
}
}
Using generic T, we can use the same methods to save other types of records
To call:
var person1 = new Person()
{
name = "jhon",
};
var person2 = new Person()
{
name = "another jhon",
};
var personList = new List<Person>();
personList.Add(person1);
personList.Add(person2);
var pathXml = #"C:\testes\xml";
var fileName = "persons.xml";
var dataProvider = DataProvider.GetInstance();
var itsSaved = dataProvider.SaveToXml<Person>(personList, pathXml, fileName);
var persons = dataProvider.LoadFromXml<Person>(pathXml, fileName);

issue reading from xml file c#

I am trying to read from a xml file but it is not working eventhough I have been weating over it for two days, so any help would be greatly appreciated!
In Cookbook class:
public List<Recipe> readAll()
{
List<Recipe> newListRecipies = new List<Recipe>();
Recipe readRecipie = new Recipe();
TextReader reader = null;
try
{
var serializer = new XmlSerializer(typeof(Recipe));
reader = new StreamReader(path);
newListRecipies = BinarySerialization.ReadFromBinaryFile<List<Recipe>>(path);
reader.Close();
return newListRecipies;
}
catch (Exception e)
{
string error = $"An exception occured: " + e;
Log theLog = new Log();
theLog.LogMessage(error);
return newListRecipies;
}
}
In Recipe class:
public Recipe readOne(string name)
{
CookBook newCB = new CookBook();
List<Recipe> allRecipies = newCB.readAll();
foreach(Recipe oneRecipe in allRecipies)
{
if(oneRecipe.recipeName == name)
{
return oneRecipe;
}
}return newCB.defaultRecipie;
}
I am getting the default recipe as the result everytime. I can see the the recipies are saved correctly everytime but here the code anyways:
In Recipie class:
public void SaveRecipe(Recipe myRecepie)
{
CookBook theCookBook = new CookBook();
theCookBook.Save(myRecepie);
addFoodItem(myRecepie.recipeIngridients);
}
In CookBook class:
public void Save(Recipe newRecipie)
{
TextWriter writer = null;
try
{
var serializer = new XmlSerializer(typeof(Recipe));
writer = new StreamWriter(path, append: true);
serializer.Serialize(writer, newRecipie);
}
finally
{
if (writer != null)
writer.Close();
}
}
And the xml file (generated by the save function in the CookBook class)
<?xml version="1.0" encoding="utf-8"?>
<Recipe xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<recipeName>toast</recipeName>
<recipeType>snack</recipeType>
<recipeIngridients>
<string>bread</string>
<string>butter</string>
</recipeIngridients>
</Recipe><?xml version="1.0" encoding="utf-8"?>
<Recipe xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<recipeName>G&T</recipeName>
<recipeType>drink</recipeType>
<recipeIngridients>
<string>tonic</string>
<string>gin</string>
</recipeIngridients>
</Recipe><?xml version="1.0" encoding="utf-8"?>
<Recipe xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<recipeName>cake</recipeName>
<recipeType>snack</recipeType>
<recipeIngridients>
<string>butter</string>
<string>sugar</string>
</recipeIngridients>
</Recipe>

I believe the way you are deserializing the xml is incorrect with BinarySerialization.ReadFromBinaryFile....
Assuming your xml is correct I would do something like this.
// read file
List<Recipe> recipes;
using (var reader = new StreamReader("recipe.xml"))
{
XmlSerializer deserializer = new XmlSerializer(typeof(List<Recipe>),
new XmlRootAttribute("Recipe"));
recipes = (List<Recipe>)deserializer.Deserialize(reader);
}

These are the changes I made. It's best to load the previous recipes, add to the list, then re-write the XML from scratch.
public class Recipe
{
public string recipeName;
public string recipeType;
public List<string> recipeIngridients = new List<string>();
public Recipe readOne(string name)
{
CookBook newCB = new CookBook();
List<Recipe> allRecipies = newCB.readAll();
foreach(Recipe oneRecipe in allRecipies)
{
if(oneRecipe.recipeName == name)
{
return oneRecipe;
}
}
return newCB.defaultRecipe;
}
}
public class RecipeList
{
public List<Recipe> Recipes = new List<Recipe>();
}
public class CookBook
{
public Recipe defaultRecipe;
public string path;
public void Save(Recipe newRecipe)
{
TextWriter writer = null;
RecipeList recipeList = null;
try
{
// See if recipes exists
var serializer = new XmlSerializer(typeof(RecipeList));
if (File.Exists(path)) // Load the recipe list if it exists
{
using (var fileStream = File.OpenRead(path))
{
recipeList = (RecipeList)serializer.Deserialize(fileStream);
}
}
else
{
recipeList = new RecipeList();
}
// Add recipe to the list
recipeList.Recipes.Add(newRecipe);
writer = new StreamWriter(path, append: false);
serializer.Serialize(writer, recipeList);
}
finally
{
if (writer != null)
writer.Close();
}
}
public List<Recipe> readAll()
{
RecipeList temp = null;
var serializer = new XmlSerializer(typeof(RecipeList));
try
{
using (var fileStream = File.OpenRead(path))
{
temp = (RecipeList)serializer.Deserialize(fileStream);
}
return temp.Recipes;
}
catch (Exception e)
{
string error = #"An exception occured: " + e;
//Log theLog = new Log();
//theLog.LogMessage(error);
return new List<Recipe>();
}
}
}

'System.NotSupportedException' in mscorlib.ni.dll Memory stream is not expandable

I am getting the error "Exception thrown: 'System.NotSupportedException' in mscorlib.ni.dll Memory stream is not expandable" when trying to serialize and save an instance of a custom class object.
Here are my saving/loading methods:
public void SerializeObject<T>(T serializableObject, string fileName)
{
if (serializableObject == null) { return; }
try
{
XmlDocument xmlDocument = new XmlDocument();
XmlSerializer serializer = new XmlSerializer(serializableObject.GetType());
using (MemoryStream stream = new MemoryStream())
{
// convert string to stream
byte[] byteArray = Encoding.UTF8.GetBytes(fileName);
MemoryStream fileNameStream = new MemoryStream(byteArray);
serializer.Serialize(stream, serializableObject);
stream.Position = 0;
xmlDocument.Load(stream);
xmlDocument.Save(fileNameStream);
stream.Dispose();
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
Debug.WriteLine(TAG + serializableObject.ToString() + " saved");
}
public T DeSerializeObject<T>(string fileName)
{
if (string.IsNullOrEmpty(fileName)) { return default(T); }
T objectOut = default(T);
try
{
string attributeXml = string.Empty;
// convert string to stream
byte[] byteArray = Encoding.UTF8.GetBytes(fileName);
MemoryStream stream = new MemoryStream(byteArray);
XmlDocument xmlDocument = new XmlDocument();
xmlDocument.Load(stream);
string xmlString = xmlDocument.OuterXml;
using (StringReader read = new StringReader(xmlString))
{
Type outType = typeof(T);
XmlSerializer serializer = new XmlSerializer(outType);
using (XmlReader reader = XmlReader.Create(read))
{
objectOut = (T)serializer.Deserialize(reader);
reader.Dispose();
}
read.Dispose();
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
if (objectOut != null) Debug.WriteLine(TAG + objectOut.ToString() + " loaded");
return objectOut;
}
And here is the object class that I'm trying to save:
public class EntryDataType
{
readonly string TAG = "EntryDataType: ";
private static int idCounter = -1;
public int id;
private EntryDataType parentEdt;
public EntryDataType parentEdtProperty
{
get { return parentEdt; }
set { parentEdt = value; }
}
// row control is not serializable, so ignore it when saving
[XmlIgnore]
public RowControl linkedRowControl;
public int indent = -1;
public int index = -1;
public int linearIndex = -1;
private bool completed = false;
public bool completedProperty {
get { return completed; }
set
{
// set hidden state and set all children's hidden state, i.e. they will do the same
completed = value;
foreach (var item in childList)
{
item.linkedRowControl.SetCompleted(value);
}
}
}
public ChildList<EntryDataType> childList;
public bool bulletButtonChecked;
public string textboxText;
public EntryDataType()
{
// assign unique id to each entry
id = idCounter;
idCounter++;
//Debug.WriteLine(TAG + "new entry " + id + " created");
childList = new ChildList<EntryDataType>();
childList.parentEdtOfChildListProperty = this;
}
}
I've already rewritten the class to eliminate it's constructor's parameters, and to ignore the unserializeable RowControl member. I am just learning .NET and c# so don't fully know what I'm doing yet; any help is greatly appreciated. Thanks :)

OK, I think I see what you are trying to do - serialize and deserialize an object to/from a file. Your way is a bit complicated, it could be simplified, for example like this:
public static void SerializeObject<T>(T serializableObject, string fileName)
{
if (serializableObject == null) { return; }
try
{
XmlSerializer serializer = new XmlSerializer(serializableObject.GetType());
using (Stream stream = File.Open(fileName, FileMode.Create))
{
serializer.Serialize(stream, serializableObject);
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
}
public static T DeSerializeObject<T>(string fileName)
{
if (string.IsNullOrEmpty(fileName)) { return default(T); }
try
{
XmlSerializer serializer = new XmlSerializer(typeof(T));
using (Stream stream = File.Open(fileName, FileMode.Open))
{
return (T)serializer.Deserialize(stream);
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
return default(T);
}
There is no need to read/write to a MemoryStream first. You can serialize and deserialize straight from the file.
Also, when using using, there is no need to dispose the object (like your stream.Dispose(); line) - that's what the dispose is for (with the added bonus that if there's an exception, the object will be disposed as well).
I haven't tried this with your class but it should work fine. Give it a try and see if it works.

byte[] byteArray = Encoding.UTF8.GetBytes(fileName);
MemoryStream fileNameStream = new MemoryStream();
...
xmlDocument.Save(fileNameStream);

Cant serialize respose from oauth RESTful webservice - Error in XML Doc(1,2)

I've been looking for an answr for this for hours now and the more i read the more confused i seem to get! Basically as the question implies, i'm trying to serialise a response from my web service but cant convert the xml back to an object
First off my web service has this class object
[Serializable()]
[XmlRootAttribute("WcfRESTful")]
public class testcc
{
[System.Xml.Serialization.XmlElement("field1")]
public string f1 { get; set; }
[System.Xml.Serialization.XmlElement("field2")]
public string f2 { get; set; }
[System.Xml.Serialization.XmlElement("field3")]
public string f3 { get; set; }
public testcc() { }
public testcc(string _f1, string _f2, string _f3)
{
f1 = _f1;
f2 = _f2;
f3 = _f3;
}
}
To serialize the data on the web service side i do the following
public string GetTest_With_OAuth(string username)
{
if (Authenticate(WebOperationContext.Current.IncomingRequest))
{
try
{
//Serialize emp in the xmlTextWriter
List<testcc> emplist = new List<testcc>();
testcc emp = new testcc("Hello","Some", "Person");
string XmlizedString = StringSerialize(emp);
return XmlizedString;
}
catch (Exception ex)
{
errHandler err = new errHandler();
err.ErrorMessage = ex.Message.ToString();
throw;
}
}
else
{
//Invalid User
}
}
private string StringSerialize(testcc data)
{
TextWriter w = WriterSerialize(data);
string xml = w.ToString();
w.Close();
return xml;
}
private TextWriter WriterSerialize(testcc data)
{
TextWriter w = new StringWriter();
this.s = new XmlSerializer(typeof(WcfRESTful.testcc));
s.Serialize(w, data);
w.Flush();
return w;
}
So basically it returns me back the following data as a string which i then attempt to serialize
<string xmlns="http://schemas.microsoft.com/2003/10/Serialization/"><?xml version="1.0" encoding="utf-16"?> <WcfRESTful xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <field1>Hello</field1> <field2>Some</field2> <field3>Person</field3> </WcfRESTful></string>
This is the code i use to deserialize
public testcc DeserializeString(string xml)
{
TextReader reader = new StringReader(xml);
return Deserialize(reader);
}
public testcc Deserialize(TextReader reader)
{
testcc o = (testcc)s.Deserialize(reader);
reader.Close();
return o;
}
Everytime though it is failing on testcc o = (testcc)s.Deserialize(reader);with There is an error in XML document (1, 2) and i cant seem to figure it out but it is basically the last thing i need to do for my webservice id=f anyone has any input i'd appreciate it. I'm not sure if it has something to do with the tags or even how to remove them :/
Edit
On the client side i'm parsing the webresponse as follows
serilizer serializer = new serilizer();
try
{
string xml = string.Empty;
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
xml = reader.ReadToEnd();
reader.Close();
}
testcc item = serializer.DeserializeString(xml);
}
catch(Exception ex)
{
Response.Write(ex.Message);
}
I have a breakpoint at testcc item = serializer.DeserializeString(xml); where i am having a look at the string xml variable

Multiple root element (DataContractSerializer)

I'm trying to deserialize file by using DataContractSerializer. I have such class:
[DataContract]
public class kontenerUstawienia
{
[DataMember]
public int[] stanGry;
[DataMember]
public int maxSize;
[DataMember]
public int[] stanOpcji;
[DataMember]
public int numerFlagi1;
[DataMember]
public int numerFlagi2;
public kontenerUstawienia()
{
}
(...)
}
Inside, after saving serialized class instance to the file, I read the file and try to deserialize:
try
{
zapiszObiektUstawien((kontenerUstawienia)deserializer.ReadObject(strumien));
}
catch (SerializationException e)
{
System.Diagnostics.Debug.WriteLine("\n\n\n\n++++++\n" +
e.Message
+ "\n+++++++++++++++++++++++++++++++++++++++++++++++");
}
catch prints me:
++++++
There was an error deserializing the object of type
WindowsPhoneGame1.kontenerUstawienia. There are multiple root elements. Line 1,
position 599.
+++++++++++++++++++++++++++++++++++++++++++++++
What am I doing wrong?
EDIT:
Here is code that I serialize and save:
public void zapiszDoPliku(string sciezkaDoPliku, IsolatedStorageFile katalog)
{
IsolatedStorageFileStream strumien = katalog.CreateFile(sciezkaDoPliku); // tworzenie pliku
MemoryStream ms = new MemoryStream();
StreamReader r = new StreamReader(ms);
DataContractSerializer serializer = new DataContractSerializer(typeof(kontenerUstawienia));
serializer.WriteObject(ms, this);
ms.Position = 0;
string daneDoZapisania = r.ReadToEnd();
byte[] bytes = Encoding.Unicode.GetBytes(daneDoZapisania);
strumien.Write(bytes, 0, bytes.Length);
ms.Close();
strumien.Close();
}
EDIT2:
File saved:
File is here

Are you sure that the file was empty before writing?