Develop Reference

Choose one of two system attributes

I need to create configurator which read/write xml configs.
Part of config is in the following form:
<camera>
<id>1</id>
<name>Camera 1</name>
<address>http://192.168.1.100</address>
<roi>
<rect>
<x>100</x>
<y>200</y>
<width>300</width>
<height>150</height>
</rect>
<rect>
<x>350</x>
<y>400</y>
<width>200</width>
<height>250</height>
</rect>
</roi>
</camera>
But an output I need in form with xml attributes:
<camera id="1" name="Camera 1" address="http://192.168.1.100">
<roi>
<rect x="100" y="200" width="300" height="150 />
<rect x="350" y="400" width="200" height="250 />
</roi>
</camera>
I create a class for every main node, but I was wondering how to choose if property for deserialization should be XmlElement and for serialization should be XmlAttribute. Or have I create two separate classes for first form of xml and for the second one? I am beginner in C# and .NET so also any points and suggestions to do it in other way?
C# code:
[System.Serializable()]
public class CamerasConfigAttrib
{
private int id;
private string name;
private string address;
private Collection<Rectangle> roi;
[XmlAttribute("id", Form = XmlSchemaForm.Unqualified)]
public int Id
{
get { return id; }
set { id = value; }
}
[XmlAttribute("name", Form = XmlSchemaForm.Unqualified)]
public string Name
{
get { return name; }
set { name = value; }
}
[XmlAttribute("address", Form = XmlSchemaForm.Unqualified)]
public string Address
{
get { return address; }
set { address = value; }
}
[XmlArray("roi", Form = XmlSchemaForm.Unqualified)]
[XmlArrayItem("rect", typeof(Rectangle), Form = XmlSchemaForm.Unqualified]
public Collection<Rectangle> Roi
{
get { return roi; }
set
{
foreach (var rect in value)
roi.Add(rect);
}
}
}

Use XmlAttributeOverrides to serialize you object to another structure (you can use it to deserialize also). Here Is a short sample how you can use it in your case:
[Serializable]
[XmlRoot("camera")]
public class CamerasConfigAttrib : IXmlSerializable
{
[XmlElement("id")]
public int Id { get; set; }
[XmlElement("name")]
public string Name { get; set; }
}
Process code:
// sample data
var xml = #"<camera><id>1</id><name>Camera 1</name></camera>";
// deserialization according to a native attributes
var camera = (CamerasConfigAttrib)new XmlSerializer(typeof(CamerasConfigAttrib))
.Deserialize(new StringReader(xml));
// prepare overridings
var overrides = new XmlAttributeOverrides();
overrides.Add(typeof (CamerasConfigAttrib), "Id",
new XmlAttributes
{
XmlAttribute = new XmlAttributeAttribute("Id")
});
overrides.Add(typeof(CamerasConfigAttrib), "Name",
new XmlAttributes
{
XmlAttribute = new XmlAttributeAttribute("name")
});
// serializer initiated with overridings
var s = new XmlSerializer(typeof(CamerasConfigAttrib), overrides);
var sb = new StringBuilder();
s.Serialize(new StringWriter(sb), camera);
Result
<?xml version="1.0" encoding="utf-16"?>
<camera xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" Id="1" name="Camera 1" />
Seems to me this way is more natural, and doesn't require additional classes or files.
As an alternative you can implement interface IXmlSerializable, it gives more flexibility but it's a bit more complex

Is it possible to xml-serialize a property (in a xml serialized class) that returns a list of string objects?

I have a class, lets call it, Employee, that has a list of qualifications as property
[XmlRoot("Employee")]
public class Employee
{
private string name;
private IListManager<string> qualification = new ListManager<string>();
public Employee()
{
}
[XmlElement("Name")]
public string Name
{
get
{
return name;
}
set
{
if (value != null)
{
name = value;
}
}
}
public ListManager<string> QualificationList
{
get
{
return qualification as ListManager<string>;
}
}
[XmlElement("Qual")]
public string Qualifications
{
get
{
return ReturnQualifications();
}
}
private string ReturnQualifications()
{
string qual = string.Empty;
for (int i = 0; i < qualification.Count; i++)
{
qual += " " + qualification.GetElement(i);
}
return qual;
}
public override String ToString()
{
String infFormat = String.Format("{0, 1} {1, 15}", this.name, Qualifications);
return infFormat;
}
}
}
Then I have a method that serializes the above class tom XML by taking a list of Employees as patameter, the method is generic:
public static void Serialize<T>(string path, T typeOf)
{
XmlSerializer xmlSer = new XmlSerializer(typeof(T));
TextWriter t = new StreamWriter(path);
try
{
xmlSer.Serialize(t, typeOf);
}
catch
{
throw;
}
finally
{
if (t != null)
{
t.Close();
}
}
}
This is how I call the method XMLSerialize:
controller.XMLSerialize<Employee>(opnXMLFileDialog.FileName, employeeList);
The result of the method execution returns a file and is shown below:
<?xml version="1.0" encoding="utf-8"?>
<ArrayOfEmployees xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<Employees>
<Name>g</Name>
</Employees>
</ArrayOfEmployees>
as you can see there is only the property name included in the file. How do I proceed from here and serialize the list of qualifications too? Any suggestionswill be greatly appreciated.
Thanks in advance.

In order to serialize a property, XmlSerializer requires that the property have both a public setter and public getter. So whatever property you choose to serialize your qualifications must have a setter as well as a getter.
The obvious solution would be for your QualificationList to have a setter as well as a getter:
public ListManager<string> QualificationList
{
get
{
return qualification as ListManager<string>;
}
set
{
qualification = value;
}
}
If for some reason this cannot be done -- perhaps because your ListManager<string> class is not serializable -- you could serialize and deserialize it as a proxy array of strings, like so:
[XmlIgnore]
public ListManager<string> QualificationList
{
get
{
return qualification as ListManager<string>;
}
}
[XmlElement("Qual")]
[Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
[DebuggerBrowsable(DebuggerBrowsableState.Never)]
public string[] QualificationArray
{
get
{
return Enumerable.Range(0, qualification.Count).Select(i => qualification.GetElement(i)).ToArray();
}
set
{
// Here I am assuming your ListManager<string> class has Clear() and Add() methods.
qualification.Clear();
if (value != null)
foreach (var str in value)
{
qualification.Add(str);
}
}
}
Then for the following employee list:
var employee = new Employee() { Name = "Mnemonics" };
employee.QualificationList.Add("posts on stackoverflow");
employee.QualificationList.Add("easy to remember");
employee.QualificationList.Add("hard to spell");
var list = new List<Employee>();
list.Add(employee);
The following XML is generated:
<?xml version="1.0" encoding="utf-16"?>
<ArrayOfEmployee xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<Employee>
<Name>Mnemonics</Name>
<Qual>posts on stackoverflow</Qual>
<Qual>easy to remember</Qual>
<Qual>hard to spell</Qual>
</Employee>
</ArrayOfEmployee>
Is that satisfactory?

Serialization: How to Deserialize in C#

How can I deserialize the string based on what I have done in this method? Basically, what I have here is to pass the string through the network using serialization and deserialize the string in order to convey the message. But once I managed to receive the message, I have no idea if what I'm doing is correct. Here's the code:
string ConvertToString(FrogGame np, Frog1 pm, Frog2 pm2) //Serialization. the three parameters are the classes.
{
XmlSerializer sendSerializer = new XmlSerializer(typeof(FrogGame),new Type[]{typeof(Frog1),typeof(Frog2)});
StreamWriter myWriter = new StreamWriter(#"pad1.xml");
sendSerializer.Serialize(myWriter, np);
sendSerializer.Serialize(myWriter, pm);
sendSerializer.Serialize(myWriter, pm2);
return myWriter.ToString();
} //Overall, I serialize it into string
Once I pass the string through the network, I want to deserialize it in order the pass the message to the classes. How do I continue here onwards? How can I edit? The code:
void StringReceived(string str) //so str is myWriter.ToString()
{
XmlSerializer revSerializer = new XmlSerializer(typeof(FrogGame), new Type[] { typeof(Frog1), typeof(Frog2) });
FileStream myFileStream = new FileStream(#"pad1.xml", FileMode.Open);
FrogGame b = (FrogGame)revSerializer.Deserialize(myFileStream);
if (b is Frog1)
{
if (Network.IsServer())
{
pm = (Frog1)b;
pm.Position.Y = b.pm.Position.Y;
pm.Position.X = b.pm.Position.X;
}
else
{
System.Diagnostics.Debug.WriteLine("BAD Message: " + msg);
}
}
else if (b is Frog2)
{
if (Network.IsClient())
{
pm2 = (PaddleMessage2)b;
pm2.Position.Y = b.pm2.Position.Y;
pm2.Position.X = b.pm2.Position.X;
}
else
{
System.Diagnostics.Debug.WriteLine("BAD Message: " + msg);
}
}
}

I might misinterpret your problem, but I why don't you put all the thing you want to save in a class and do it like this (plus, if you use class, your data "transportation" and "management" will be much easier) :
SERIALIZATION
XmlSerializer serializer = new XmlSerializer(typeof(FrogGameData));
TextWriter textWriter = new StreamWriter("FrogGameSaveFile.xml");
serializer.Serialize(textWriter, _frogGameData);
textWriter.Close();
DESERIALIZATION
XmlSerializer deserializer = new XmlSerializer(typeof(FrogGameData));
TextReader textReader = new StreamReader("FrogGameSaveFile.xml");
_frogGameData = (FrogGameData)deserializer.Deserialize(textReader);
textReader.Close();
Note : The need-to-be-saved field should have property, because the tag in the XML will mimic the property name.
Additional Note : FrogGameData is not different than a normal class for automatic serialization like this. The XML will mimic your property order in the class for the one in the XML file.
But if you wanna need to rearrange the XML tag placement, you could do something like [XmlElement(Order = 1)],[XmlElement(Order = 2)], etc on top of your property to customize the order in XML file.
UPDATE
In case you need it, this is an example of your FrogGameData class :
public class FrogGameData
{
private Frog _frog1;
private Frog _frog2;
public Frog Frog1
{
get { return _frog1; }
set { _frog1 = value; }
}
public Frog Frog2
{
get { return _frog2; }
set { _frog2 = value; }
}
}
And the XML will pretty much like this :
<?xml version="1.0" encoding="utf-8"?>
<FrogGameData>
<Frog1>Something-depends-on-your-data</Frog1>
<Frog2>Something-depends-on-your-data</Frog2>
</FrogGameData>
But, if your class is (Note the XmlElement part) :
public class FrogGameData
{
private Frog _frog1;
private Frog _frog2;
[XmlElement(Order = 2)]
public Frog Frog1
{
get { return _frog1; }
set { _frog1 = value; }
}
[XmlElement(Order = 1)]
public Frog Frog2
{
get { return _frog2; }
set { _frog2 = value; }
}
}
Then, your XML will be :
<?xml version="1.0" encoding="utf-8"?>
<FrogGameData>
<Frog2>Something-depends-on-your-data</Frog2>
<Frog1>Something-depends-on-your-data</Frog1>
</FrogGameData>

XML Serialization - XmlCDataSection as Serialization.XmlText

I am having problems serializing a cdata section using c#
I need to serialize XmlCDataSection object property as the innertext of the element.
The result I am looking for is this:
<Test value2="Another Test">
<![CDATA[<p>hello world</p>]]>
</Test>
To produce this, I am using this object:
public class Test
{
[System.Xml.Serialization.XmlText()]
public XmlCDataSection value { get; set; }
[System.Xml.Serialization.XmlAttributeAttribute()]
public string value2 { get; set; }
}
When using the xmltext annotation on the value property the following error is thrown.
System.InvalidOperationException:
There was an error reflecting property
'value'. --->
System.InvalidOperationException:
Cannot serialize member 'value' of
type System.Xml.XmlCDataSection.
XmlAttribute/XmlText cannot be used to
encode complex types
If I comment out the annotation, the serialization will work but the cdata section is placed into a value element which is no good for what I am trying to do:
<Test value2="Another Test">
<value><![CDATA[<p>hello world</p>]]></value>
</Test>
Can anybody point me in the right direction to getting this to work.
Thanks, Adam

Thanks Richard, only now had chance to get back to this. I think I have resolved the problem by using your suggestion. I have created a CDataField object using the following:
public class CDataField : IXmlSerializable
{
private string elementName;
private string elementValue;
public CDataField(string elementName, string elementValue)
{
this.elementName = elementName;
this.elementValue = elementValue;
}
public XmlSchema GetSchema()
{
return null;
}
public void WriteXml(XmlWriter w)
{
w.WriteStartElement(this.elementName);
w.WriteCData(this.elementValue);
w.WriteEndElement();
}
public void ReadXml(XmlReader r)
{
throw new NotImplementedException("This method has not been implemented");
}
}

The way Test is defined, your data is a CData object. So the serialisation system is trying to preserve the CData object.
But you want to serialise some text data as a CData section.
So first, the type of Test.value should be String.
You then need to control how that field is serialised, but there does not appear to be any inbuilt method or attribute to control how strings are serialised (as string, maybe with entities for reserved characters, or as CDATA). (Since, from an XML infoset perspective all of these are the same, this is not surprising.)
You can of course implemented IXmlSerializable and just code the serialisation of the Test type yourself which gives you complete control.

This basically shorter version of Jack answer with better error messages:
[XmlIgnore]
public string Content { get; set; }
[XmlText]
public XmlNode[] ContentAsCData
{
get => new[] { new XmlDocument().CreateCDataSection(Content) };
set => Content = value?.Cast<XmlCDataSection>()?.Single()?.Data;
}

Just found an alternative from here:
[XmlIgnore]
public string Content { get; set; }
[XmlText]
public XmlNode[] CDataContent
{
get
{
var dummy = new XmlDocument();
return new XmlNode[] {dummy.CreateCDataSection(Content)};
}
set
{
if (value == null)
{
Content = null;
return;
}
if (value.Length != 1)
{
throw new InvalidOperationException(
String.Format(
"Invalid array length {0}", value.Length));
}
var node0 = value[0];
var cdata = node0 as XmlCDataSection;
if (cdata == null)
{
throw new InvalidOperationException(
String.Format(
"Invalid node type {0}", node0.NodeType));
}
Content = cdata.Data;
}
}
}

I had very same problem as Adam. However this Answer does not helped me at 100% :) but gives me a clue. So I'va created a code like below. It generates XML like this:
<Actions>
<Action Type="reset">
<![CDATA[
<dbname>longcall</dbname>
<ontimeout>
<url>http://[IPPS_ADDRESS]/</url>
<timeout>10</timeout>
</ontimeout>
]]>
</Action>
<Action Type="load">
<![CDATA[
<dbname>longcall</dbname>
]]>
</Action>
</Actions>
Code:
public class ActionsCDataField : IXmlSerializable
{
public List<Action> Actions { get; set; }
public ActionsCDataField()
{
Actions = new List<Action>();
}
public XmlSchema GetSchema()
{
return null;
}
public void WriteXml(XmlWriter w)
{
foreach (var item in Actions)
{
w.WriteStartElement("Action");
w.WriteAttributeString("Type", item.Type);
w.WriteCData(item.InnerText);
w.WriteEndElement();
w.WriteString("\r\n");
}
}
public void ReadXml(XmlReader r)
{
XmlDocument xDoc = new XmlDocument();
xDoc.Load(r);
XmlNodeList nodes = xDoc.GetElementsByTagName("Action");
if (nodes != null && nodes.Count > 0)
{
foreach (XmlElement node in nodes)
{
Action a = new Action();
a.Type = node.GetAttribute("Type");
a.InnerText = node.InnerXml;
if (a.InnerText != null && a.InnerText.StartsWith("<![CDATA[") && a.InnerText.EndsWith("]]>"))
a.InnerText = a.InnerText.Substring("<![CDATA[".Length, a.InnerText.Length - "<![CDATA[]]>".Length);
Actions.Add(a);
}
}
}
}
public class Action
{
public String Type { get; set; }
public String InnerText { get; set; }
}

.Net XmlSerializer: deserialize CDATA being inner text

I have a problem with CDATA deserialization using standard .Net XmlSerializer.
Update: I get XML from external system and I can't influence it's format so I can't make CData be enclosed in a separate Element of Attribute.
Serialization gives this:
<?xml version="1.0" encoding="utf-16"?>
<MyClass xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><![CDATA[Hello, world!]]></MyClass>
Deserialization does not restore object to it's original state.
Here's class that is being serialized:
public class MyClass
{
string _data;
[XmlIgnore]
public string Data
{
get { return _data; }
set { _data = value; }
}
[XmlAnyElement]
public XmlCDataSection CData
{
get { return new XmlDataDocument().CreateCDataSection(Data); }
set { Data = value.Value; }
}
}
Here's the test which fails:
[Test]
public void CData_as_inner_text_test()
{
MyClass item = new MyClass();
item.Data = "Hello, world!";
XmlSerializer serializer = new XmlSerializer(item.GetType());
string serialized;
using (StringWriter sw = new StringWriter())
{
serializer.Serialize(sw, item);
serialized = sw.GetStringBuilder().ToString();
}
MyClass deserialized;
using (StringReader sr = new StringReader(serialized))
{
deserialized = (MyClass)serializer.Deserialize(sr);
}
Assert.AreEqual(item.Data, deserialized.Data); // For some reason, deserialized.Data == null
}
I found the same problem here but there's no answer:
XmlSerializer, XmlAnyElement and CDATA

The CData property ends up null, because the content of the CDATA section ends up in the Data property, where it is being ignored...
<MyClass><![CDATA[Hello, world!]]></MyClass>
is absolutely equivalent to:
<MyClass>Hello, world!</MyClass>
You shouldn't care whether the external app writes the content of MyClass as CData or not. Likewise, the external app shouldn't care how you write it out.
IOW, this should be all you need:
public class MyClass
{
string _data;
[XmlText]
public string Data
{
get { return _data; }
set { _data = value; }
}
}

First declare a property as XmlCDataSection
public XmlCDataSection ProjectXml { get; set; }
in this case projectXml is a string xml
ProjectXml = new XmlDocument().CreateCDataSection(projectXml);
when you serialize your message you will have your nice format (notice )
<?xml version="1.0" encoding="utf-16"?>
<MessageBase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xsi:type="Message_ProjectStatusChanged">
<ID>131</ID>
<HandlerName>Plugin</HandlerName>
<NumRetries>0</NumRetries>
<TriggerXml><![CDATA[<?xml version="1.0" encoding="utf-8"?><TmData xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" Version="9.0.0" Date="2012-01-31T15:46:02.6003105" Format="1" AppVersion="10.2.0" Culture="en-US" UserID="0" UserRole=""><PROJECT></PROJECT></TmData>]]></TriggerXml>
<MessageCreatedDate>2012-01-31T20:28:52.4843092Z</MessageCreatedDate>
<MessageStatus>0</MessageStatus>
<ProjectId>0</ProjectId>
<UserGUID>8CDF581E44F54E8BAD60A4FAA8418070</UserGUID>
<ProjectGUID>5E82456F42DC46DEBA07F114F647E969</ProjectGUID>
<PriorStatus>0</PriorStatus>
<NewStatus>3</NewStatus>
<ActionDate>0001-01-01T00:00:00</ActionDate>
</MessageBase>