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How to write strings and bool to a text file (comma separated)

I am trying to make a winform application. The app has 2 textboxes (firstName, lastName), a numericUpDown, and a checkbox. The app is able to read from a text file, with comma separated rows (Daniel,Brown,26,true). The app put this info in a listbox. Then you can add a new user. When you are finished adding users you press save and the new info from lisbox will be saved in that text file. I've created the read file script and add user succesfully. However I can't create the save user button so that it'll save: Daniel,Brown,26,true. I was able to save as: Daniel,Brown,26,happy.
Here is the Person Class:
public class Person
{
public string FirstName { get; set; }
public string LastName { get; set; }
public string Age { get; set; }
public bool IsHappy { get; set; }
public override string ToString()
{
var statusText = IsHappy ? "happy" : "not happy";
return $"{FirstName} {LastName} is {Age} and is {statusText}";
}
}
Here is the form.cs with it's script:
public partial class ChallengeForm : Form
{
private BindingList<Person> _persons = new BindingList<Person>();
private PersonsService _personsService;
public ChallengeForm()
{
_personsService = new PersonsService();
InitializeComponent();
WireUpDropDown();
}
private void WireUpDropDown()
{
_persons = new BindingList<Person>(_personsService.GetPersons(#"C:\Users\user\Desktop\Document.TXT"));
usersListBox.DataSource = _persons;
}
private void addUserButton_Click(object sender, EventArgs e)
{
var person = new Person { FirstName = firstNameText.Text, LastName = lastNameText.Text, Age = agePicker.Text, IsHappy = isHappyCheckbox.Checked };
_persons.Add(person);
}
private void saveListButton_Click(object sender, EventArgs e)
{
}
}
My question is how can I convert the status back to bool. And write the listbox to the text file as csv. I would be very thankfull if you could use SoC.
Here is what I've tried:
const string sPath = (#"C:\Users\user\Desktop\Document.TXT");
System.IO.StreamWriter SaveFile = new System.IO.StreamWriter(sPath);
SaveFile.Write(myperson);
foreach (var item in usersListBox.Items)
{
List<string> unwantedWords = new List<string> { "is", "and" };
var linesSplitted = item.ToString().Split(' ').ToList();
var wordsWithoutUnwantedWords = linesSplitted.Where(i => !unwantedWords.Contains(i)).ToList();
for (int i = 0; i<wordsWithoutUnwantedWords.Count; i++)
{
var isLastWord = i == wordsWithoutUnwantedWords.Count - 1;
SaveFile.Write(wordsWithoutUnwantedWords[i]);
if (!isLastWord)
{
SaveFile.Write(",");
}

Look into XML Serialization. You can just pass in your filepath and the object and the rest will be done for you by the Serialisation classes. Code below:
This is taken from DeadlyDog's awesome answer: https://stackoverflow.com/a/22417240/1623971
/// <summary>
/// Writes the given object instance to an XML file.
/// <para>Only Public properties and variables will be written to the file. These can be any type though, even other classes.</para>
/// <para>If there are public properties/variables that you do not want written to the file, decorate them with the [XmlIgnore] attribute.</para>
/// <para>Object type must have a parameterless constructor.</para>
/// </summary>
/// <typeparam name="T">The type of object being written to the file.</typeparam>
/// <param name="filePath">The file path to write the object instance to.</param>
/// <param name="objectToWrite">The object instance to write to the file.</param>
/// <param name="append">If false the file will be overwritten if it already exists. If true the contents will be appended to the file.</param>
public static void WriteToXmlFile<T>(string filePath, T objectToWrite, bool append = false) where T : new()
{
TextWriter writer = null;
try
{
var serializer = new XmlSerializer(typeof(T));
writer = new StreamWriter(filePath, append);
serializer.Serialize(writer, objectToWrite);
}
finally
{
if (writer != null)
writer.Close();
}
}
/// <summary>
/// Reads an object instance from an XML file.
/// <para>Object type must have a parameterless constructor.</para>
/// </summary>
/// <typeparam name="T">The type of object to read from the file.</typeparam>
/// <param name="filePath">The file path to read the object instance from.</param>
/// <returns>Returns a new instance of the object read from the XML file.</returns>
public static T ReadFromXmlFile<T>(string filePath) where T : new()
{
TextReader reader = null;
try
{
var serializer = new XmlSerializer(typeof(T));
reader = new StreamReader(filePath);
return (T)serializer.Deserialize(reader);
}
finally
{
if (reader != null)
reader.Close();
}
}
Sample use case:
WriteToXmlFile<Person>("C:\someClass.txt", objectToSerialize);
// Read the file contents back into a variable.
Person deserializedObject = ReadFromXmlFile<Person>("C:\someClass.txt");

Convert stream to object with generics [duplicate]

I have heard that Json.NET is faster than DataContractJsonSerializer, and wanted to give it a try...
But I couldn't find any methods on JsonConvert that take a stream rather than a string.
For deserializing a file containing JSON on WinPhone, for example, I use the following code to read the file contents into a string, and then deserialize into JSON. It appears to be about 4 times slower in my (very ad-hoc) testing than using DataContractJsonSerializer to deserialize straight from the stream...
// DCJS
DataContractJsonSerializer dc = new DataContractJsonSerializer(typeof(Constants));
Constants constants = (Constants)dc.ReadObject(stream);
// JSON.NET
string json = new StreamReader(stream).ReadToEnd();
Constants constants = JsonConvert.DeserializeObject<Constants>(json);
Am I doing it wrong?

The current version of Json.net does not allow you to use the accepted answer code. A current alternative is:
public static object DeserializeFromStream(Stream stream)
{
var serializer = new JsonSerializer();
using (var sr = new StreamReader(stream))
using (var jsonTextReader = new JsonTextReader(sr))
{
return serializer.Deserialize(jsonTextReader);
}
}
Documentation: Deserialize JSON from a file stream

public static void Serialize(object value, Stream s)
{
using (StreamWriter writer = new StreamWriter(s))
using (JsonTextWriter jsonWriter = new JsonTextWriter(writer))
{
JsonSerializer ser = new JsonSerializer();
ser.Serialize(jsonWriter, value);
jsonWriter.Flush();
}
}
public static T Deserialize<T>(Stream s)
{
using (StreamReader reader = new StreamReader(s))
using (JsonTextReader jsonReader = new JsonTextReader(reader))
{
JsonSerializer ser = new JsonSerializer();
return ser.Deserialize<T>(jsonReader);
}
}

UPDATE: This no longer works in the current version, see below for correct answer (no need to vote down, this is correct on older versions).
Use the JsonTextReader class with a StreamReader or use the JsonSerializer overload that takes a StreamReader directly:
var serializer = new JsonSerializer();
serializer.Deserialize(streamReader);

I've written an extension class to help me deserializing from JSON sources (string, stream, file).
public static class JsonHelpers
{
public static T CreateFromJsonStream<T>(this Stream stream)
{
JsonSerializer serializer = new JsonSerializer();
T data;
using (StreamReader streamReader = new StreamReader(stream))
{
data = (T)serializer.Deserialize(streamReader, typeof(T));
}
return data;
}
public static T CreateFromJsonString<T>(this String json)
{
T data;
using (MemoryStream stream = new MemoryStream(System.Text.Encoding.Default.GetBytes(json)))
{
data = CreateFromJsonStream<T>(stream);
}
return data;
}
public static T CreateFromJsonFile<T>(this String fileName)
{
T data;
using (FileStream fileStream = new FileStream(fileName, FileMode.Open))
{
data = CreateFromJsonStream<T>(fileStream);
}
return data;
}
}
Deserializing is now as easy as writing:
MyType obj1 = aStream.CreateFromJsonStream<MyType>();
MyType obj2 = "{\"key\":\"value\"}".CreateFromJsonString<MyType>();
MyType obj3 = "data.json".CreateFromJsonFile<MyType>();
Hope it will help someone else.

I arrived at this question looking for a way to stream an open ended list of objects onto a System.IO.Stream and read them off the other end, without buffering the entire list before sending. (Specifically I'm streaming persisted objects from MongoDB over Web API.)
#Paul Tyng and #Rivers did an excellent job answering the original question, and I used their answers to build a proof of concept for my problem. I decided to post my test console app here in case anyone else is facing the same issue.
using System;
using System.Diagnostics;
using System.IO;
using System.IO.Pipes;
using System.Threading;
using System.Threading.Tasks;
using Newtonsoft.Json;
namespace TestJsonStream {
class Program {
static void Main(string[] args) {
using(var writeStream = new AnonymousPipeServerStream(PipeDirection.Out, HandleInheritability.None)) {
string pipeHandle = writeStream.GetClientHandleAsString();
var writeTask = Task.Run(() => {
using(var sw = new StreamWriter(writeStream))
using(var writer = new JsonTextWriter(sw)) {
var ser = new JsonSerializer();
writer.WriteStartArray();
for(int i = 0; i < 25; i++) {
ser.Serialize(writer, new DataItem { Item = i });
writer.Flush();
Thread.Sleep(500);
}
writer.WriteEnd();
writer.Flush();
}
});
var readTask = Task.Run(() => {
var sw = new Stopwatch();
sw.Start();
using(var readStream = new AnonymousPipeClientStream(pipeHandle))
using(var sr = new StreamReader(readStream))
using(var reader = new JsonTextReader(sr)) {
var ser = new JsonSerializer();
if(!reader.Read() || reader.TokenType != JsonToken.StartArray) {
throw new Exception("Expected start of array");
}
while(reader.Read()) {
if(reader.TokenType == JsonToken.EndArray) break;
var item = ser.Deserialize<DataItem>(reader);
Console.WriteLine("[{0}] Received item: {1}", sw.Elapsed, item);
}
}
});
Task.WaitAll(writeTask, readTask);
writeStream.DisposeLocalCopyOfClientHandle();
}
}
class DataItem {
public int Item { get; set; }
public override string ToString() {
return string.Format("{{ Item = {0} }}", Item);
}
}
}
}
Note that you may receive an exception when the AnonymousPipeServerStream is disposed, I ignored this as it isn't relevant to the problem at hand.

another option that is handy when you are running out of memory is to periodically flush
/// <summary>serialize the value in the stream.</summary>
/// <typeparam name="T">the type to serialize</typeparam>
/// <param name="stream">The stream.</param>
/// <param name="value">The value.</param>
/// <param name="settings">The json settings to use.</param>
/// <param name="bufferSize"></param>
/// <param name="leaveOpen"></param>
public static void JsonSerialize<T>(this Stream stream,[DisallowNull] T value, [DisallowNull] JsonSerializerSettings settings, int bufferSize=1024, bool leaveOpen=false)
{
using (var writer = new StreamWriter(stream,encoding: System.Text.Encoding.UTF32,bufferSize,leaveOpen))
using (var jsonWriter = new JsonTextWriter(writer))
{
var ser = JsonSerializer.Create( settings );
ser.Serialize(jsonWriter, value);
jsonWriter.Flush();
}
}
/// <summary>serialize the value in the stream asynchronously.</summary>
/// <typeparam name="T"></typeparam>
/// <param name="stream">The stream.</param>
/// <param name="value">The value.</param>
/// <param name="settings">The settings.</param>
/// <param name="bufferSize">The buffer size, in bytes, set -1 to not flush till done</param>
/// <param name="leaveOpen"> true to leave the stream open </param>
/// <param name="cancellationToken">Propagates notification that operations should be canceled.</param>
public static Task JsonSerializeAsync<T>(this Stream stream,[DisallowNull] T value, [DisallowNull] JsonSerializerSettings settings, int bufferSize=1024, bool leaveOpen=false, CancellationToken cancellationToken=default)
{
using (var writer = new StreamWriter(stream,encoding: System.Text.Encoding.UTF32,bufferSize: bufferSize,leaveOpen: leaveOpen))
using (var jsonWriter = new JsonTextWriter(writer))
{
var ser = JsonSerializer.Create( settings );
ser.Serialize(jsonWriter, value);
return jsonWriter.Flush();
}
//jsonWriter.FlushAsnc with my version gives an error on the stream
return Task.CompletedTask;
}
You can test/ use it like so:
[TestMethod()]
public void WriteFileIntoJsonTest()
{
var file = new FileInfo(Path.GetTempFileName());
try
{
var list = new HashSet<Guid>();
for (int i = 0; i < 100; i++)
{
list.Add(Guid.NewGuid());
}
file.JsonSerialize(list);
var sr = file.IsValidJson<List<Guid>>(out var result);
Assert.IsTrue(sr);
Assert.AreEqual<int>(list.Count, result.Count);
foreach (var item in result)
{
Assert.IsFalse(list.Add(item), $"The GUID {item} should already exist in the hash set");
}
}
finally
{
file.Refresh();
file.Delete();
}
}
you'd need to create the extension methods, here is the whole set:
public static class JsonStreamReaderExt
{
static JsonSerializerSettings _settings ;
static JsonStreamReaderExt()
{
_settings = JsonConvert.DefaultSettings?.Invoke() ?? new JsonSerializerSettings();
_settings.ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor;
_settings.DateTimeZoneHandling = DateTimeZoneHandling.Utc;
_settings.DateFormatHandling = DateFormatHandling.IsoDateFormat ;
}
/// <summary>
/// serialize the value in the stream.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="stream">The stream.</param>
/// <param name="value">The value.</param>
public static void JsonSerialize<T>(this Stream stream,[DisallowNull] T value)
{
stream.JsonSerialize(value,_settings);
}
/// <summary>
/// serialize the value in the file .
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="file">The file.</param>
/// <param name="value">The value.</param>
public static void JsonSerialize<T>(this FileInfo file,[DisallowNull] T value)
{
if (string.IsNullOrEmpty(file.DirectoryName)==true && Directory.Exists(file.DirectoryName) == false)
{
Directory.CreateDirectory(file.FullName);
}
using var s = file.OpenWrite();
s.JsonSerialize(value, _settings);
file.Refresh();
}
/// <summary>
/// serialize the value in the file .
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="file">The file.</param>
/// <param name="value">The value.</param>
/// <param name="settings">the json settings to use</param>
public static void JsonSerialize<T>(this FileInfo file, [DisallowNull] T value, [DisallowNull] JsonSerializerSettings settings)
{
if (string.IsNullOrEmpty(file.DirectoryName) == true && Directory.Exists(file.DirectoryName) == false)
{
Directory.CreateDirectory(file.FullName);
}
using var s = file.OpenWrite();
s.JsonSerialize(value, settings);
file.Refresh();
}
/// <summary>
/// serialize the value in the file .
/// </summary>
/// <remarks>File will be refreshed to contain the new meta data</remarks>
/// <typeparam name="T">the type to serialize</typeparam>
/// <param name="file">The file.</param>
/// <param name="value">The value.</param>
/// <param name="cancellationToken">Propagates notification that operations should be canceled.</param>
public static async Task JsonSerializeAsync<T>(this FileInfo file, [DisallowNull] T value, CancellationToken cancellationToken = default)
{
if (string.IsNullOrEmpty(file.DirectoryName) == true && Directory.Exists(file.DirectoryName) == false)
{
Directory.CreateDirectory(file.FullName);
}
using (var stream = file.OpenWrite())
{
await stream.JsonSerializeAsync(value, _settings,bufferSize:1024,leaveOpen:false, cancellationToken).ConfigureAwait(false);
}
file.Refresh();
}
/// <summary>
/// serialize the value in the file .
/// </summary>
/// <remarks>File will be refreshed to contain the new meta data</remarks>
/// <typeparam name="T">the type to serialize</typeparam>
/// <param name="file">The file to create or overwrite.</param>
/// <param name="value">The value.</param>
/// <param name="settings">the json settings to use</param>
/// <param name="cancellationToken">Propagates notification that operations should be canceled.</param>
public static async Task JsonSerializeAsync<T>(this FileInfo file, [DisallowNull] T value, [DisallowNull] JsonSerializerSettings settings, CancellationToken cancellationToken=default)
{
if (string.IsNullOrEmpty(file.DirectoryName) == true && Directory.Exists(file.DirectoryName) == false)
{
Directory.CreateDirectory(file.FullName);
}
using (var stream = file.OpenWrite())
{
await stream.JsonSerializeAsync(value, settings,bufferSize:1024,leaveOpen:false, cancellationToken).ConfigureAwait(false);
}
file.Refresh();
}
/// <summary>serialize the value in the stream.</summary>
/// <typeparam name="T">the type to serialize</typeparam>
/// <param name="stream">The stream.</param>
/// <param name="value">The value.</param>
/// <param name="settings">The json settings to use.</param>
/// <param name="bufferSize">The buffer size, in bytes, set -1 to not flush till done</param>
/// <param name="leaveOpen"> true to leave the stream open </param>
public static void JsonSerialize<T>(this Stream stream,[DisallowNull] T value, [DisallowNull] JsonSerializerSettings settings, int bufferSize=1024, bool leaveOpen=false)
{
using (var writer = new StreamWriter(stream,encoding: System.Text.Encoding.UTF32,bufferSize,leaveOpen))
using (var jsonWriter = new JsonTextWriter(writer))
{
var ser = JsonSerializer.Create( settings );
ser.Serialize(jsonWriter, value);
jsonWriter.Flush();
}
}
/// <summary>serialize the value in the stream asynchronously.</summary>
/// <typeparam name="T"></typeparam>
/// <param name="stream">The stream.</param>
/// <param name="value">The value.</param>
/// <param name="settings">The settings.</param>
/// <param name="bufferSize">The buffer size, in bytes, set -1 to not flush till done</param>
/// <param name="leaveOpen"> true to leave the stream open </param>
/// <param name="cancellationToken">Propagates notification that operations should be canceled.</param>
public static Task JsonSerializeAsync<T>(this Stream stream,[DisallowNull] T value, [DisallowNull] JsonSerializerSettings settings, int bufferSize=1024, bool leaveOpen=false, CancellationToken cancellationToken=default)
{
using (var writer = new StreamWriter(stream,encoding: System.Text.Encoding.UTF32,bufferSize: bufferSize,leaveOpen: leaveOpen))
using (var jsonWriter = new JsonTextWriter(writer))
{
var ser = JsonSerializer.Create( settings );
ser.Serialize(jsonWriter, value);
jsonWriter.Flush();
}
return Task.CompletedTask;
}
/// <summary>
/// Determines whether [is valid json] [the specified result].
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="stream">The stream.</param>
/// <param name="result">The result.</param>
/// <returns><c>true</c> if [is valid json] [the specified result]; otherwise, <c>false</c>.</returns>
public static bool IsValidJson<T>(this Stream stream, [NotNullWhen(true)] out T? result)
{
if (stream is null)
{
throw new ArgumentNullException(nameof(stream));
}
if (stream.Position != 0)
{
stream.Seek(0, SeekOrigin.Begin);
}
JsonSerializerSettings settings = (JsonConvert.DefaultSettings?.Invoke()) ?? new JsonSerializerSettings() { DateTimeZoneHandling = DateTimeZoneHandling.Utc, DateFormatHandling = DateFormatHandling.IsoDateFormat };
settings.ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor;
using (var reader = new StreamReader(stream))
using (var jsonReader = new JsonTextReader(reader))
{
var ser = JsonSerializer.Create(settings);
try
{
result = ser.Deserialize<T>(jsonReader);
}
catch { result = default; }
}
return result is not null;
}
/// <summary>
/// Determines whether [is valid json] [the specified settings].
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="stream">The stream.</param>
/// <param name="settings">The settings.</param>
/// <param name="result">The result.</param>
/// <returns><c>true</c> if [is valid json] [the specified settings]; otherwise, <c>false</c>.</returns>
public static bool IsValidJson<T>(this Stream stream, JsonSerializerSettings settings, [NotNullWhen(true)] out T? result)
{
if (stream is null)
{
throw new ArgumentNullException(nameof(stream));
}
if (settings is null)
{
throw new ArgumentNullException(nameof(settings));
}
if (stream.Position != 0)
{
stream.Seek(0, SeekOrigin.Begin);
}
using (var reader = new StreamReader(stream))
using (var jsonReader = new JsonTextReader(reader))
{
var ser = JsonSerializer.Create(settings);
try
{
result = ser.Deserialize<T>(jsonReader);
}
catch { result = default; }
}
return result is not null;
}
/// <summary>
/// Determines whether file contains valid json using the specified settings and reads it into the output.
/// </summary>
/// <typeparam name="T">Type to convert into</typeparam>
/// <param name="file">The file.</param>
/// <param name="settings">The settings.</param>
/// <param name="result">The result.</param>
/// <returns><c>true</c> if [is valid json] [the specified settings]; otherwise, <c>false</c>.</returns>
/// <exception cref="System.ArgumentNullException">file</exception>
/// <exception cref="System.ArgumentNullException"></exception>
/// <exception cref="System.ArgumentNullException">settings</exception>
/// <exception cref="System.IO.FileNotFoundException">File could not be accessed</exception>
public static bool IsValidJson<T>(this FileInfo file, JsonSerializerSettings settings, [NotNullWhen(true)] out T? result)
{
if (file is null)
{
throw new ArgumentNullException(nameof(file));
}
if (File.Exists(file.FullName) == false)
{
throw new FileNotFoundException("File could not be accessed",fileName: file.FullName);
}
using var stream = file.OpenRead();
if (stream is null)
{
throw new ArgumentNullException(message:"Could not open the file and access the underlying file stream",paramName: nameof(file));
}
if (settings is null)
{
throw new ArgumentNullException(nameof(settings));
}
using (var reader = new StreamReader(stream))
using (var jsonReader = new JsonTextReader(reader))
{
var ser = JsonSerializer.Create(settings);
try
{
result = ser.Deserialize<T>(jsonReader);
}
catch { result = default; }
}
return result is not null;
}
/// <summary>
/// Determines whether file contains valid json using the specified settings and reads it into the output.
/// </summary>
/// <typeparam name="T">Type to convert into</typeparam>
/// <param name="file">The file.</param>
/// <param name="result">The result.</param>
/// <returns><c>true</c> if [is valid json] [the specified result]; otherwise, <c>false</c>.</returns>
/// <exception cref="System.ArgumentNullException">file</exception>
/// <exception cref="System.IO.FileNotFoundException">File could not be accessed</exception>
public static bool IsValidJson<T>(this FileInfo file, [NotNullWhen(true)] out T? result)
{
if (file is null)
{
throw new ArgumentNullException(nameof(file));
}
if (File.Exists(file.FullName) == false)
{
throw new FileNotFoundException("File could not be accessed",fileName: file.FullName);
}
JsonSerializerSettings settings =( JsonConvert.DefaultSettings?.Invoke()) ?? new JsonSerializerSettings() { DateTimeZoneHandling= DateTimeZoneHandling.Utc, DateFormatHandling= DateFormatHandling.IsoDateFormat };
settings.ConstructorHandling = ConstructorHandling.AllowNonPublicDefaultConstructor;
return file.IsValidJson<T>(settings,out result);
}
}

write list of objects to a file

I've got a class salesman in the following format:
class salesman
{
public string name, address, email;
public int sales;
}
I've got another class where the user inputs name, address, email and sales.
This input is then added to a list
List<salesman> salesmanList = new List<salesman>();
After the user has input as many salesman to the list as they like, they have the option to save the list to a file of their choice (which I can limit to .xml or .txt(which ever is more appropriate)).
How would I add this list to the file?
Also this file needs to be re-read back into a list if the user wishes to later view the records.

Something like this would work. this uses a binary format (the fastest for loading) but the same code would apply to xml with a different serializer.
using System.IO;
[Serializable]
class salesman
{
public string name, address, email;
public int sales;
}
class Program
{
static void Main(string[] args)
{
List<salesman> salesmanList = new List<salesman>();
string dir = #"c:\temp";
string serializationFile = Path.Combine(dir, "salesmen.bin");
//serialize
using (Stream stream = File.Open(serializationFile, FileMode.Create))
{
var bformatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
bformatter.Serialize(stream, salesmanList);
}
//deserialize
using (Stream stream = File.Open(serializationFile, FileMode.Open))
{
var bformatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
List<salesman> salesman = (List<salesman>)bformatter.Deserialize(stream);
}
}
}

I just wrote a blog post on saving an object's data to Binary, XML, or Json; well writing an object or list of objects to a file that is. Here are the functions to do it in the various formats. See my blog post for more details.
Binary
/// <summary>
/// Writes the given object instance to a binary file.
/// <para>Object type (and all child types) must be decorated with the [Serializable] attribute.</para>
/// <para>To prevent a variable from being serialized, decorate it with the [NonSerialized] attribute; cannot be applied to properties.</para>
/// </summary>
/// <typeparam name="T">The type of object being written to the XML file.</typeparam>
/// <param name="filePath">The file path to write the object instance to.</param>
/// <param name="objectToWrite">The object instance to write to the XML file.</param>
/// <param name="append">If false the file will be overwritten if it already exists. If true the contents will be appended to the file.</param>
public static void WriteToBinaryFile<T>(string filePath, T objectToWrite, bool append = false)
{
using (Stream stream = File.Open(filePath, append ? FileMode.Append : FileMode.Create))
{
var binaryFormatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
binaryFormatter.Serialize(stream, objectToWrite);
}
}
/// <summary>
/// Reads an object instance from a binary file.
/// </summary>
/// <typeparam name="T">The type of object to read from the XML.</typeparam>
/// <param name="filePath">The file path to read the object instance from.</param>
/// <returns>Returns a new instance of the object read from the binary file.</returns>
public static T ReadFromBinaryFile<T>(string filePath)
{
using (Stream stream = File.Open(filePath, FileMode.Open))
{
var binaryFormatter = new System.Runtime.Serialization.Formatters.Binary.BinaryFormatter();
return (T)binaryFormatter.Deserialize(stream);
}
}
XML
Requires the System.Xml assembly to be included in your project.
/// <summary>
/// Writes the given object instance to an XML file.
/// <para>Only Public properties and variables will be written to the file. These can be any type though, even other classes.</para>
/// <para>If there are public properties/variables that you do not want written to the file, decorate them with the [XmlIgnore] attribute.</para>
/// <para>Object type must have a parameterless constructor.</para>
/// </summary>
/// <typeparam name="T">The type of object being written to the file.</typeparam>
/// <param name="filePath">The file path to write the object instance to.</param>
/// <param name="objectToWrite">The object instance to write to the file.</param>
/// <param name="append">If false the file will be overwritten if it already exists. If true the contents will be appended to the file.</param>
public static void WriteToXmlFile<T>(string filePath, T objectToWrite, bool append = false) where T : new()
{
TextWriter writer = null;
try
{
var serializer = new XmlSerializer(typeof(T));
writer = new StreamWriter(filePath, append);
serializer.Serialize(writer, objectToWrite);
}
finally
{
if (writer != null)
writer.Close();
}
}
/// <summary>
/// Reads an object instance from an XML file.
/// <para>Object type must have a parameterless constructor.</para>
/// </summary>
/// <typeparam name="T">The type of object to read from the file.</typeparam>
/// <param name="filePath">The file path to read the object instance from.</param>
/// <returns>Returns a new instance of the object read from the XML file.</returns>
public static T ReadFromXmlFile<T>(string filePath) where T : new()
{
TextReader reader = null;
try
{
var serializer = new XmlSerializer(typeof(T));
reader = new StreamReader(filePath);
return (T)serializer.Deserialize(reader);
}
finally
{
if (reader != null)
reader.Close();
}
}
Json
You must include a reference to Newtonsoft.Json assembly, which can be obtained from the Json.NET NuGet Package.
/// <summary>
/// Writes the given object instance to a Json file.
/// <para>Object type must have a parameterless constructor.</para>
/// <para>Only Public properties and variables will be written to the file. These can be any type though, even other classes.</para>
/// <para>If there are public properties/variables that you do not want written to the file, decorate them with the [JsonIgnore] attribute.</para>
/// </summary>
/// <typeparam name="T">The type of object being written to the file.</typeparam>
/// <param name="filePath">The file path to write the object instance to.</param>
/// <param name="objectToWrite">The object instance to write to the file.</param>
/// <param name="append">If false the file will be overwritten if it already exists. If true the contents will be appended to the file.</param>
public static void WriteToJsonFile<T>(string filePath, T objectToWrite, bool append = false) where T : new()
{
TextWriter writer = null;
try
{
var contentsToWriteToFile = JsonConvert.SerializeObject(objectToWrite);
writer = new StreamWriter(filePath, append);
writer.Write(contentsToWriteToFile);
}
finally
{
if (writer != null)
writer.Close();
}
}
/// <summary>
/// Reads an object instance from an Json file.
/// <para>Object type must have a parameterless constructor.</para>
/// </summary>
/// <typeparam name="T">The type of object to read from the file.</typeparam>
/// <param name="filePath">The file path to read the object instance from.</param>
/// <returns>Returns a new instance of the object read from the Json file.</returns>
public static T ReadFromJsonFile<T>(string filePath) where T : new()
{
TextReader reader = null;
try
{
reader = new StreamReader(filePath);
var fileContents = reader.ReadToEnd();
return JsonConvert.DeserializeObject<T>(fileContents);
}
finally
{
if (reader != null)
reader.Close();
}
}
Example
// Write the list of salesman objects to file.
WriteToXmlFile<List<salesman>>("C:\salesmen.txt", salesmanList);
// Read the list of salesman objects from the file back into a variable.
List<salesman> salesmanList = ReadFromXmlFile<List<salesman>>("C:\salesmen.txt");

If you want to use JSON then using Json.NET is usually the best way to go.
If for some reason you are unable to use Json.NET you can use the built in JSON support found in .NET.
You will need to include the following using statement and add a reference for System.Web.Extentsions.
using System.Web.Script.Serialization;
Then you would use these to Serialize and Deserialize your object.
//Deserialize JSON to your Object
YourObject obj = new JavaScriptSerializer().Deserialize<YourObject>("File Contents");
//Serialize your object to JSON
string sJSON = new JavaScriptSerializer().Serialize(YourObject);
https://msdn.microsoft.com/en-us/library/system.web.script.serialization.javascriptserializer_methods(v=vs.110).aspx

If you want xml serialization, you can use the built-in serializer. To achieve this, add [Serializable] flag to the class:
[Serializable()]
class salesman
{
public string name, address, email;
public int sales;
}
Then, you could override the "ToString()" method which converts the data into xml string:
public override string ToString()
{
string sData = "";
using (MemoryStream oStream = new MemoryStream())
{
XmlSerializer oSerializer = new XmlSerializer(this.GetType());
oSerializer.Serialize(oStream, this);
oStream.Position = 0;
sData = Encoding.UTF8.GetString(oStream.ToArray());
}
return sData;
}
Then just create a method that writes this.ToString() into a file.
UPDATE
The mentioned above will serialize single entry as xml. If you need the whole list to be serialized, the idea would be a bit different. In this case you'd employ the fact that lists are serializable if their contents are serializable and use the serialization in some outer class.
Example code:
[Serializable()]
class salesman
{
public string name, address, email;
public int sales;
}
class salesmenCollection
{
List<salesman> salesmanList;
public void SaveTo(string path){
System.IO.File.WriteAllText (path, this.ToString());
}
public override string ToString()
{
string sData = "";
using (MemoryStream oStream = new MemoryStream())
{
XmlSerializer oSerializer = new XmlSerializer(this.GetType());
oSerializer.Serialize(oStream, this);
oStream.Position = 0;
sData = Encoding.UTF8.GetString(oStream.ToArray());
}
return sData;
}
}

trying to serialize and deserialize entity object in c#

I am using two methods below to serialize/deserialize entity framework object (ver. 4.0).
I tried several ways to accomplish this, and had no luck. Serialization works fine. I get nice xml formatted string, but when I try to deserialize I get error in XML. How is that possible?
Thanks.
public static string SerializeObject(Object obj)
{
XmlSerializer ser = new XmlSerializer(obj.GetType());
System.Text.StringBuilder sb = new System.Text.StringBuilder();
System.IO.StringWriter writer = new System.IO.StringWriter(sb);
ser.Serialize(writer, obj);
XmlDocument doc = new XmlDocument();
doc.LoadXml(sb.ToString());
string xml = doc.InnerXml;
return xml;
}
public static object DeSerializeAnObject(string xml, Type objType)
{
XmlDocument doc = new XmlDocument();
doc.LoadXml(xml);
XmlNodeReader reader = new XmlNodeReader(doc.DocumentElement);
XmlSerializer ser = new XmlSerializer(objType);
object obj = ser.Deserialize(reader);
return obj;
}

I use generic methods to serialize and deserialize:
/// <summary>
/// Serializes an object to Xml as a string.
/// </summary>
/// <typeparam name="T">Datatype T.</typeparam>
/// <param name="ToSerialize">Object of type T to be serialized.</param>
/// <returns>Xml string of serialized type T object.</returns>
public static string SerializeToXmlString<T>(T ToSerialize)
{
string xmlstream = String.Empty;
using (MemoryStream memstream = new MemoryStream())
{
XmlSerializer xmlSerializer = new XmlSerializer(typeof(T));
XmlTextWriter xmlWriter = new XmlTextWriter(memstream, Encoding.UTF8);
xmlSerializer.Serialize(xmlWriter, ToSerialize);
xmlstream = UTF8ByteArrayToString(((MemoryStream)xmlWriter.BaseStream).ToArray());
}
return xmlstream;
}
/// <summary>
/// Deserializes Xml string of type T.
/// </summary>
/// <typeparam name="T">Datatype T.</typeparam>
/// <param name="XmlString">Input Xml string from which to read.</param>
/// <returns>Returns rehydrated object of type T.</returns>
public static T DeserializeXmlString<T>(string XmlString)
{
T tempObject = default(T);
using (MemoryStream memoryStream = new MemoryStream(StringToUTF8ByteArray(XmlString)))
{
XmlSerializer xs = new XmlSerializer(typeof(T));
XmlTextWriter xmlTextWriter = new XmlTextWriter(memoryStream, Encoding.UTF8);
tempObject = (T)xs.Deserialize(memoryStream);
}
return tempObject;
}
// Convert Array to String
public static String UTF8ByteArrayToString(Byte[] ArrBytes)
{ return new UTF8Encoding().GetString(ArrBytes); }
// Convert String to Array
public static Byte[] StringToUTF8ByteArray(String XmlString)
{ return new UTF8Encoding().GetBytes(XmlString); }

i THINK the issue is with this line:
string xml = doc.InnerXml;
you want ALL the xml, not just the xml inside the root node.

Just return sb.ToString(), loading into the XmlDocument is not doing anything.

Some redundancies and usings was excluded. Refactored and cleaned up:
namespace MyProject
{
using System.IO;
using System.Text;
using System.Xml;
using System.Xml.Serialization;
public static class Serializer
{
#region Public Methods and Operators
/// <summary>
/// Deserializes Xml string of type T.
/// </summary>
/// <typeparam name="T">Datatype T.</typeparam>
/// <param name="XmlString">Input Xml string from which to read.</param>
/// <returns>Returns rehydrated object of type T.</returns>
public static T DeserializeXmlString<T>(string xmlString)
{
T tempObject;
using (var memoryStream = new MemoryStream(StringToUTF8ByteArray(xmlString)))
{
var xs = new XmlSerializer(typeof(T));
tempObject = (T)xs.Deserialize(memoryStream);
}
return tempObject;
}
/// <summary>
/// Serializes an object to Xml as a string.
/// </summary>
/// <typeparam name="T">Datatype T.</typeparam>
/// <param name="toSerialize">Object of type T to be serialized.</param>
/// <returns>Xml string of serialized type T object.</returns>
public static string SerializeToXmlString<T>(T toSerialize)
{
string xmlstream;
using (var memstream = new MemoryStream())
{
var xmlSerializer = new XmlSerializer(typeof(T));
var xmlWriter = new XmlTextWriter(memstream, Encoding.UTF8);
xmlSerializer.Serialize(xmlWriter, toSerialize);
xmlstream = UTF8ByteArrayToString(((MemoryStream)xmlWriter.BaseStream).ToArray());
}
return xmlstream;
}
#endregion
#region Methods
private static byte[] StringToUTF8ByteArray(string xmlString)
{
return new UTF8Encoding().GetBytes(xmlString);
}
private static string UTF8ByteArrayToString(byte[] arrBytes)
{
return new UTF8Encoding().GetString(arrBytes);
}
#endregion
}
}

How to change XML Attribute

How can I change an attribute of an element in an XML file, using C#?

Mike;
Everytime I need to modify an XML document I work it this way:
//Here is the variable with which you assign a new value to the attribute
string newValue = string.Empty;
XmlDocument xmlDoc = new XmlDocument();
xmlDoc.Load(xmlFile);
XmlNode node = xmlDoc.SelectSingleNode("Root/Node/Element");
node.Attributes[0].Value = newValue;
xmlDoc.Save(xmlFile);
//xmlFile is the path of your file to be modified
I hope you find it useful

Using LINQ to xml if you are using framework 3.5:
using System.Xml.Linq;
XDocument xmlFile = XDocument.Load("books.xml");
var query = from c in xmlFile.Elements("catalog").Elements("book")
select c;
foreach (XElement book in query)
{
book.Attribute("attr1").Value = "MyNewValue";
}
xmlFile.Save("books.xml");

If the attribute you want to change doesn't exist or has been accidentally removed, then an exception occurs. I suggest you first create a new attribute and send it to a function like the following:
private void SetAttrSafe(XmlNode node,params XmlAttribute[] attrList)
{
foreach (var attr in attrList)
{
if (node.Attributes[attr.Name] != null)
{
node.Attributes[attr.Name].Value = attr.Value;
}
else
{
node.Attributes.Append(attr);
}
}
}
Usage:
XmlAttribute attr = dom.CreateAttribute("name");
attr.Value = value;
SetAttrSafe(node, attr);

Here's the beginnings of a parser class to get you started. This ended up being my solution to a similar problem:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Xml.Linq;
namespace XML
{
public class Parser
{
private string _FilePath = string.Empty;
private XDocument _XML_Doc = null;
public Parser(string filePath)
{
_FilePath = filePath;
_XML_Doc = XDocument.Load(_FilePath);
}
/// <summary>
/// Replaces values of all attributes of a given name (attributeName) with the specified new value (newValue) in all elements.
/// </summary>
/// <param name="attributeName"></param>
/// <param name="newValue"></param>
public void ReplaceAtrribute(string attributeName, string newValue)
{
ReplaceAtrribute(string.Empty, attributeName, new List<string> { }, newValue);
}
/// <summary>
/// Replaces values of all attributes of a given name (attributeName) with the specified new value (newValue) in elements with a given name (elementName).
/// </summary>
/// <param name="elementName"></param>
/// <param name="attributeName"></param>
/// <param name="newValue"></param>
public void ReplaceAtrribute(string elementName, string attributeName, string newValue)
{
ReplaceAtrribute(elementName, attributeName, new List<string> { }, newValue);
}
/// <summary>
/// Replaces values of all attributes of a given name (attributeName) and value (oldValue)
/// with the specified new value (newValue) in elements with a given name (elementName).
/// </summary>
/// <param name="elementName"></param>
/// <param name="attributeName"></param>
/// <param name="oldValue"></param>
/// <param name="newValue"></param>
public void ReplaceAtrribute(string elementName, string attributeName, string oldValue, string newValue)
{
ReplaceAtrribute(elementName, attributeName, new List<string> { oldValue }, newValue);
}
/// <summary>
/// Replaces values of all attributes of a given name (attributeName), which has one of a list of values (oldValues),
/// with the specified new value (newValue) in elements with a given name (elementName).
/// If oldValues is empty then oldValues will be ignored.
/// </summary>
/// <param name="elementName"></param>
/// <param name="attributeName"></param>
/// <param name="oldValues"></param>
/// <param name="newValue"></param>
public void ReplaceAtrribute(string elementName, string attributeName, List<string> oldValues, string newValue)
{
List<XElement> elements = _XML_Doc.Elements().Descendants().ToList();
foreach (XElement element in elements)
{
if (elementName == string.Empty | element.Name.LocalName.ToString() == elementName)
{
if (element.Attribute(attributeName) != null)
{
if (oldValues.Count == 0 || oldValues.Contains(element.Attribute(attributeName).Value))
{ element.Attribute(attributeName).Value = newValue; }
}
}
}
}
public void SaveChangesToFile()
{
_XML_Doc.Save(_FilePath);
}
}
}