XML - Serialize class - Some questions

Question

I have the idea of serializing the properties of a class to a XML-file and then upload this file to a server. This is because I want to download this file again and read out the serialized content.

So a structure like this:

File exists (myfile.xml) -> Serialize data from a class (myclass.cs) to the file -> Upload the file.

Now the content could look something like this:

<?xml version="1.0"?>

-<MyClass xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">

<SomeProperty>0.1.0.0</SomeProperty>
<SomePropertiesChild>Test</SomePropertiesChild>

</MyClass>

Well, so this is not the problem, I have built a class to serialize the data to the file, so that it looks like above.

The problem now is, that I do not know how to go on. I want that the next time new data will be serialized like that, but it should be attached to that XML-file, not a new one. So I download this file and then serialize new data as attachment to it, so that it will look the following:

<?xml version="1.0"?>

-<MyClass xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">

<SomeProperty>0.1.0.0</SomeProperty>
<SomePropertiesChild>Test</SomePropertiesChild>
<!-- This is the part that should be attached -->
<SomeProperty>0.2.0.0</SomeProperty>
<SomePropertiesChild>Test2</SomePropertiesChild>

</MyClass>

And this should be repeated as many times as I want: download file, serialize new data and attach it to this one, then upload it again. Now, the second point is, that I want to read this out.

For that I use the XML-class, too. For the type param for the type that the data should be serialized to, I set the class that contains the properties. But now, I have more nodes of the same name in my XML like above. I want to separate this now. So, not only that one class, but for each node with the same name a new class.

To show you that a bit clearer:

In the XML we have the first pair (SomeProperty, SomePropertiesChild). This one should be deserialized to myclass.cs now, which contains the right properties for the XML-nodes. Example:

public class MyClass
{
   public Version SomeProperty {get; set;}
   public string SomeProeprtiesChild {get; set;}
}

And then the first XML-pair should be deserialized to that class. But I want to do this for each XML-"pair" in my XML-file, but I can't get a right structure in my head. Should I make a List here or how should I do that? I really hope I could explain it a bit clearly, it is very difficult to explain. Also I do not know how to do this with the attaching. Any tips?

If you have questions, ask !

Answer 1

What you are looking for is not simply serialization. You want to serialize the same object more than once right?

A possible solution is to serialize a List<MyClass> and append new instances to the list if the file exists.

Answer 2

In short, there is no built-in way to do what it is you are looking for. However, that doesn't mean it can't be done...

The simplest, and closest built-in, way would be to maintain a List<MyClass> which you update whenever you upload/download etc. and serialize. However, this wouldn't get the exact XML you want, this would produce something along the lines of

<ListOfMyClass>
    <MyClass>
        <Property>1</Property>
        ...
    </MyClass>
    <MyClass>
        <Property>2</Property>
        ...
    </MyClass>
</ListOfMyClass>

The more complex approach would be to have MyClass implement IXmlSerializable and override the behaviour of WriteXml / ReadXml to handle your custom XML format.