XML in .Net?

[Dillinger4]

This is a question for anyone that uses XML at their job. Does most of the XML related programming you do involve serializing classes to XML or creating XML documents programmatically using XMLWriters? Thanks.

[Edneeis]

Most of the work I do with XML is through the DataSet Object, maybe for user settings, small amounts of data, or whatever.

[funkycoder]

HI

which method to open xml-files is easier to use:

- with Dataset
- with System.XML
- with MSXML 3

is there another way?

[Edneeis]

I guess it depends whats in the XML file or what you want to do with it. The good part about using the dataset is it loads the XML file right in and then you have it as tables and rows which is easy to work with. If you already know the schema then you can make a typed dataset and even use the intellisense to help you with the structure.

[funkycoder]

I want to use it as a File format.
I want to save 4 Bitmap with some extra data (2 collections with ~20 Objects)

[Edneeis]

For that you could just make a class and serialize it to a file. Although the collection may give you trouble unless all the items are serializable.

[funkycoder]

ok, and how can i do this???

(could you give me a little code-snippet...?)

thanks, funkycoder

[Dillinger4]

Hey Edneeis here is another question. If you don't mind. When changing the format of XML do you use serialization with source code style attributes or do you just opt to use XSLT?

[Edneeis]

Originally posted by Dilenger4
Hey Edneeis here is another question. If you don't mind. When changing the format of XML do you use serialization with source code style attributes or do you just opt to use XSLT?

I'm sorry I'm not sure what you mean. If there is a decent chance that the structure of the XML will change then I'd probably just load the xml file into an untyped dataset. Altough it would take a bit of work for the program to then make use of the new stuff. An untyped dataset just uses the generic tables() rows() arrays or collections so your code would still work but if you change the format then the data might be in the wrong spot. If you use a typed dataset then it actually has the properties from the XLS including attributes and stuff. I guess it really depends on what you are trying to accomplish.

[Edneeis]

As for funkycoder, I was just trying and it doesn't look like you can easily serialize a collection since it may contain objects that are not serializable. Whats in the collection?

Here is some code to show you serialization (one way anyway):

'here are the imports
Imports System.IO
Imports System.Runtime.Serialization
Imports System.Runtime.Serialization.Formatters.Binary
 
 
'Code for a click event or somethign in a form or whatever
        'make test object and put somethign in it
        Dim obj As New MyFileFormat()
        obj.MyData = "Testing"
 
        'serialize it to a file
        Dim fs As FileStream = New FileStream(Path.Combine(Application.StartupPath, "test.mff"), FileMode.OpenOrCreate)
        Dim bf As New BinaryFormatter()
        bf.Serialize(fs, obj)
        bf = Nothing
        fs.Close()
        fs = Nothing
 
        'get it back from a file
        fs = New FileStream(Path.Combine(Application.StartupPath, "test.mff"), FileMode.OpenOrCreate)
        bf = New BinaryFormatter()
 
        'make new object to hold it
        Dim obj2 As MyFileFormat
        obj2 = bf.Deserialize(fs)
        bf = Nothing
        fs.Close()
        fs = Nothing
 
        'show the results
        MsgBox(obj2.MyData)
 
 
 
'sample class that is serializable
<Serializable()> _
 Public Class MyFileFormat
    'Public MyObjects As New Collection()
    Public MyImages(4) As Image
    Public MyData As String
End Class

That will at least get you started if you choose that route.

[Dillinger4]

I was just actualy reading an article on using soure code style attributes vs XSLT and i started to wonder what is most commonly used on the job. Probably bolth though. For instance say that i wanted to serialize a class as XML.

Import System.Xml.Serialization
 
Class Ser
  Dim tc As theclass = New theclass("Mickey","Mouse")
  Dim ser As XmlSerializer = New XmlSerializer(GetType(theclass))
 
  ser.Serialize(Console.out, the class)
End Class 
 
Class theclass
  Public fname As String
  Public lname As String
 
  Public Sub New()
 
  End Sub
 
Public Sub New(ByVal fname As String, ByVal lname As String)
     Me.fname  = fname 
     Me.lname  = lname     
     
  End Sub
End Class

But now say that i wanted to change the elements to conform to a german standard. We could use the source code style attribute
XmlElementAttribute like the following.

Class theclass
  <XmlElementAttribute("Vorname")>Public fname As String
   Public fname As String
  <XmlElementAttribute("Zuname")>Public lname As String
  Public lname As String
  
 
  Public Sub New()
 
  End Sub
 
 Public Sub New(ByVal fname As String, ByVal lname As String)
     Me.fname  = fname 
     Me.lname  = lname
 
  End Sub
End Class

Im pretty sure this is how it could be done but i have to look into using XSLT further since i think that is the main purpose if XSLT(to change the underlying Xml structure)

[Dillinger4]

Any luck funkycoder? Edneeis does raise an interesting point. What is in the collection?

[funkycoder]

Hi

I've tried both ways - Binary Serialization and XML Serialization and it works both perfect!
But I don't know, which I should use.

The Binary Files are smaller, but when someone opens a file and deletes a space-char the file is "destoried"

The XML-File is more secure, but when I save a (binary) Bitmap-file within it would become extremely big!

~

[Dillinger4]

Yeah im not sure which way would be best but at least you got it working.