Hi again,

This time I'm trying to write XML logfiles for my web application. The VS.NET help guide confuses me by suplying me with tons of code wich doesn't make sense at all.

So I wanted to know if anyone knows howto write a simple XML file like this:

<NewEntry sessionId="<session>">
  <Entry name="EntryText">This is a sample entry</Entry>
  <Entry name="Client IP">0.0.0.0</Entry>
</NewEntry>

Reading it is another thing, but this is the main part, since writing and reading is almost the same (according to VS.NET). Anyone have any ideas?

Thanks

I'll have a look

MorningZ...

Nice piece of code

thanks..

it could be a little cleaner/less-lines-of-code than it is.. but i wrote that last year when i was just starting to mess around with .NET code.....

i think people are losing fact that XML used to store data, such as in config file, shouldn't be treated as a text file, but rather as a representation of data...

you can add/remove/update items/parameters/nodes/whatever just like you were updating records in a database, its just a matter of coding syntax....

but for sure one's gotta start with getting out of the "text file/File System Object" thinking

There is no difference between going to the database and filling a DataSet, like:
Dim objConn As new OleDBConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\db\this.mdb")
Dim objCmd As new OleDbDataAdapter("SELECT * FROM SITE_Config", objConn)
Dim ds As DataSet = new DataSet()
objCmd.Fill(ds,"tblUsers")

or using the "LoadXML" method to fill a DataSet, like:
Dim dsImageInfo as New DataSet()
dsImageInfo.ReadXml( CheckForXMLFile() )

once its in the DataSet, you can manipulate, go through and find, change, add data just like any record set ( http://www.4guysfromrolla.com/webtech/chapters/ASPNET/ch06.6.shtml - this article shows some syntax in the "Building a DataTable Programmatically" section ), and at the end, there is a http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdatadatasetclasstopic.asp - "WriteXML" method to resave the file

you asked "how" above my reply, i gave you an answer (although thats not the only way, just the easiest to understand from what i have run across)...

your option to "get into" datasets and making working with XML more .NET-like and less TextFile-like

I'm working on it! I've build a website which completely runs on a Site.config file, so I can read it, but updating is a different story .

heh, talk about timing :)

http://aspnet.4guysfromrolla.com/articles/112603-1.aspx - http://aspnet.4guysfromrolla.com/articles/112603-1.aspx

for sure check it out

Thanks! That little piece of code changed the way I handle XML! Using datasets never really occurred to me..

Anyway, I have the following situation (New code always causes new problems)

<?xml version="1.0" encoding="utf-8" ?>

<Configuration>

<Cryptography>

<Key1> 710398740561298347056981239847105601928347019856029384719856 012934098</Key1>

<Key2> 091098703948701928709870981230986501928370651982706519283470 615347913</Key2>

</Cryptography>
</Configuration>

Now I want to retrieve the keys, so I made the following line of code:

 objDataSet.Tables.Item("Cryptography").Columns("Key1").ToStr ing

 Fantastic. I forgot about the .Rows(0).. Anyway, thanks, now I can also update it the same way (little modified, but same idea)!

yeah, open that above xml file you posted in Visual Studio.NET

then click the "Data" tab on the bottom..... hey look! its a DataSet

the article nails it right in the head in the second paragraph:

"Sometimes, though, for smaller Web sites or for small amounts of data, a database seems like a bit of overkill"

if its a small site, a few logins, then an XML document should be fine (in fact, you can stash some username/password combos in the security areas of config.web)

XML is not by any means a replacement for a database, if the sites gets busy, lots or big XML files will be very hard to manage

"Access has limited connections".. that's a very common misconception.. Access has limited concurrent connections (meaning hitting the site at the same exact time, just because there might be 200 people on the site doesn't mean there's 200 simulatanious hits on the database), compared to SQL server.. not compared to just anything.....

Mmm, I guess I'll take SQL, AND XML . XML for auth, and SQL for the rest of the site (lots of DB involved).

EDIT: Exactly the other way. XML for the rest of the site (.config files) and SQL/Acces for auth.

Help! Got a new error.. What's wrong with the following code?

Dim objDataSet As New DataSet, objDatarow As DataRow

 objDataSet.ReadXml(HttpContext.Current.Server.MapPath("/Conf iguration/Authorization/Users.config")) 
objDatarow.Item("AccountTest") = "Boe!"
objDatarow.Item("AccountTest2") = "Boe!^2"
objDataSet.Tables.Add("Account.TestEntry")
 objDataSet.Tables("Account.TestEntry").Columns.Add("AccountT est")
 objDataSet.Tables("Account.TestEntry").Columns.Add("AccountT est2")
objDataSet.Tables("Account.TestEntry").Rows.Add(objDatarow)
 objDataSet.WriteXml(HttpContext.Current.Server.MapPath("/Con figuration/Authorization/Users.config")) 

I get the 'Object reference not set to an instance of an object' error on line 30, where I attemp to add some variables to the datarow. I've tried

Dim objDatarow As New Datarow()

But that won't work either. What's wrong?

This works alright, by the way, thanks! Quite weird, I tried this before.

EDIT, The New DataRow doesn't work, it tells me this:

'System.Data.Datarow.Protected Sub New (builder As System.Data.Datarowbuilder)' is not accessible in this content because it is 'Protected'

What should I do now?

Mart wrote: Try objDatarow As New DataRow. But if not dont use a datarow, i didnt. Instead use a array according to the columns index i.e.

You said I had to try the new.. Anyway, the array works, but I was wondering how to use the datarow, since the collum index changes a lot, and with datarow you can tell what the content is with the name of the collumn.

Xpath? Have you tried:

Dim dataset As New Dataset

Dataset.ReadXML("Blala.xml")
Dataset.Select("YourQuery", xx)

... (error)

What am I doing wrong with this one? The .Select() should return a datarow, but it won't accept it.

Dim objDataSet As New DataSet, objDataRow As DataRow

 objDataSet.ReadXml(HttpContext.Current.Server.MapPath("/Conf iguration/Account.config"))
objDataRow = objDataSet.Tables("Account").Select("AccountName = '" & "Test" & "' And AccountPassword = '" & "Bah" & "'")

... is half the work. Thx

private const localURL as String = " http://localhost/quickstart/howto/samples/Xml/QueryXmldocumentXPath/cs/books.xml - http://localhost/quickstart/howto/samples/Xml/QueryXmlDocume ntXPath/cs/books.xml "

Shared sub Main
    Dim myQueryXmlDocumentXPathSample as QueryXmlDocumentXPathSample
    myQueryXmlDocumentXPathSample = new QueryXmlDocumentXPathSample()
    myQueryXmlDocumentXPathSample.Run(localURL)
end sub

public sub Run(args as String)
    Console.WriteLine("XPath Test started ...")

    Dim myXPathDocument as XPathDocument = new XPathDocument(args)
    Dim myXPathNavigator as XPathNavigator = myXPathDocument.CreateNavigator()

    ' Get all the book prices
    XPathQuery(myXPathNavigator, "descendant::book/price")

    ' Get the ISBN of the last book
    XPathQuery(myXPathNavigator, "bookstore/book[3]/@ISBN")
end sub

private sub XPathQuery(myXPathNavigator as XPathNavigator, xpathexpr as String )

    try
        Console.WriteLine("XPath query: " + xpathexpr)

        ' Create a node interator to select nodes and move through them (read-only)
        Dim myXPathNodeIterator as XPathNodeIterator  =  myXPathNavigator.Select (xpathexpr)

        while (myXPathNodeIterator.MoveNext())
             Console.WriteLine("<" & myXPathNodeIterator.Current.Name + "> " & myXPathNodeIterator.Current.Value)
        end while

        Console.WriteLine()
    catch e as Exception
        Console.WriteLine ("Exception: {0}", e.ToString())
    end try
end sub