creating composite XML documents

[David L]

Apologise for a question from someone new to XML.

I would like to create through program (e.g. VB6), a valid and well
formed XML document which consists of embedded XML documents of
various types (e.g. SVG, schema, etc).

Reason I want to do this is that I want a clean method of storing all
related XML documents in a single record, and later extract embedded
XML documents from a container document using XML parser functions.

I suppose if such things are possible, the characters used by the
dependent XML documents have to be remapped so as not to confuse the
parser for the main document.

Another way is for me to pack the dependent XML document into a zip
file, but then I end up with binary, whereas XML is text based. Are
there functions to convert a binary file of around 500K bytes into an
XML compatible text format?

Am I asking too much of commonly available XML tools, based on the
state of implementation of this rapidly changing technology?

Thanks in advance for help provided.

QRDavid
24 Dec 2003

 

[Patrick TJ McPhee]

% I would like to create through program (e.g. VB6), a valid and well
% formed XML document which consists of embedded XML documents of
% various types (e.g. SVG, schema, etc).

If you have a DTD for every document you'll want to store, you
could store them without any escaping at all. Your DTD would be
something like

<!ELEMENT records (record+)>
<!ELEMENT record (rdoc*)>
<!ATTLIST record whatever CDATA #IMPLIED
information CDATA #IMPLIED
you CDATA #IMPLIED
need CDATA #IMPLIED>

<!ELEMENT rdoc (html|spec|book)>
<!ATTLIST rdoc name CDATA #IMPLIED
etc CDATA #IMPLIED>

<!ENTITY % htmldtd PUBLIC "-//W3C/DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
%htmldtd;
<!ENTITY % specdtd PUBLIC "-//W3C//DTD Specifciation V2.1//EN"
"http://www.w3.org/XML/1998/06/xmlspec-v21.dtd">
%specdtd;
<!ENTITY % dbookdtd PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
"http://www.oasis-open.org/docbook/xml/4.0/docbookx.dtd">
%dbookdtd;


It's much easier if you don't need to validate, of course -- since your
embedded documents will be well-formed, you can stick them in without
worrying about the DTD at all. If you really need to validate, then
you might have to change your embedded documents to ensure that, say,
every SVG file has the same namespace prefix. In that case, You might find
it easier (but surely less useful) to follow your first instinct and embed
the documents as a big chunk of text. You might also find it easier to
store them in a database rather than an XML file, or to leave them as
OS files and put links in a master index..

[...]

% I suppose if such things are possible, the characters used by the
% dependent XML documents have to be remapped so as not to confuse the
% parser for the main document.

You can get away with replacing every `<' with `&lt;' and every `&' with
`&amp;'. You could also put each document in a CDATA section. These start
with `<![CDATA[' and end with `]]>'. You'll need to scan the document for
instances of `]]>' and deal with them appropriately.

<whatever><![CDATA[< and &]]></whatever>

could be stored as

<![CDATA[<whatever><![CDATA[< and &]]>]]><![CDATA[</whatever>]]>


% Another way is for me to pack the dependent XML document into a zip
% file, but then I end up with binary, whereas XML is text based. Are
% there functions to convert a binary file of around 500K bytes into an
% XML compatible text format?

The common thing is to use mime base-64 encoding. There's probably code
for this that you can use, but the idea is to break the binary data
down into groups of 6 bits (sextets), and use each sextet as an index
into an array of 64 printable characters.

% Am I asking too much of commonly available XML tools, based on the
% state of implementation of this rapidly changing technology?

You're not asking for much, but this may not be the best way to achieve
any useful objectives.

 

[GIMME]

This code steps through an spreadsheet using Excel Visual Basic.



Sub RHUS()

Open "C:\code\rh2004us.xml" For Output As #1
' change ' into '' for sqlplus after creating xml file

Sheets("RHUS").Select
Range("A1").Select


Dim i As Integer
Dim s As String


Print #1, "<Data>"
For i = 0 To 172
s = ActiveCell.Offset(i, 0)
If "" <> s Then
t = BuildXML(i + 1, 1, "US")
'MsgBox (t)
Print #1, t
End If
Next i
Print #1, "</Data>" + Chr(10)

Close #1

End Sub

Function BuildXML(irow As Integer, ilob As Integer, c As String) As
String

Dim phdr As String
Dim ptt As String
Dim lcnt As Integer
Dim j As Integer


jct = "<CategoryName>" + Format(ActiveCell.Offset(irow - 1, 2)) +
"</CategoryName>" + Chr(10)
jcn = "<CategoryDisplayNumber>" + Format(ActiveCell.Offset(irow - 1,
3)) + "</CategoryDisplayNumber>" + Chr(10)
jhdr = "<CategoryCreate>" + Format(ActiveCell.Offset(irow - 1, 4)) +
"</CategoryCreate>" + Chr(10)

pdn = "<BundleDisplayNumber>" + Format(ActiveCell.Offset(irow - 1, 0))
+ "</BundleDisplayNumber>" + Chr(10)
ptt = "<BundleName><![CDATA[" + Format(ActiveCell.Offset(irow - 1, 1))
+ "]]></BundleName>" + Chr(10)


lob = "<LOB>" + Format(ilob) + "</LOB>" + Chr(10)
ctr = "<Country>" + c + "</Country>" + Chr(10)

lcnt = ActiveCell.Offset(irow, 1)
slabels = "<Labels>" + Chr(10)
smins = "<Min2004s>" + Chr(10)
smaxs = "<Max2004s>" + Chr(10)
seds = "<GuiEdits>" + Chr(10)

bJ = "<Bundle>" + Chr(10)
Ej = "</Bundle>" + Chr(10)

bL = "<Label>"
eL = "</Label>" + Chr(10)
bM = "<Min2004>"
eM = "</Min2004>" + Chr(10)
bN = "<Max2004>"
eN = "</Max2004>" + Chr(10)
bG = "<GuiEdit>"
eG = "</GuiEdit>" + Chr(10)

m = 0

For j = 0 To lcnt - 1
slabels = slabels + bL + ActiveCell.Offset(irow + j, 2) + eL
smins = smins + bM + Format(ActiveCell.Offset(irow + j, 3)) + eM
smaxs = smaxs + bN + Format(ActiveCell.Offset(irow + j, 4)) + eN
seds = seds + bG + ActiveCell.Offset(irow + j, 5) + eG
Next j

slabels = slabels + "</Labels>" + Chr(10)
smins = smins + "</Min2004s>" + Chr(10)
smaxs = smaxs + "</Max2004s>" + Chr(10)
seds = seds + "</GuiEdits>" + Chr(10)

BuildXML = bJ + jhdr + jct + jcn + pdn + phr + ptt + slabels + smins +
smaxs + seds + lob + ctr + Ej

End Function