XML

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]copy

Internally, WebDNA 'saves' this parsed instance as an internal variable named 'xml_var1'. This saved instance can then be referenced in the other WebDNA XML contexts on the same page.

In the example, the [include] tag is used to place the xml file contents within the [xmlparse] context. The complete XML data can be used in place of an included file.

If the source url in the [xmlparse] context contains an ampersand then it must be url'd [url]...[/url] so that any '&' in the query portion of the URL is not interpreted as a WebDNA parameter delimiter.

Example WebDNA code:

[xmlparse var=xml_var1&source=[url]http://www.domain.com?parameter1=a&parameter2=b[/url]][/xmlparse]copy

The first step to obtaining the XML nodes is to first parse the XML content using the WebDNA [xmlparse] context.

Obtaining the path parameter from the parsed XML can use three different methods: named, indexed, or xpath.

The named method expresses a literal path to the parent node, i.e. path=named:CATALOG/CD(n). If there are more than one similarly named 'sibling' nodes, then the '(n)' part specifies which node to select as part of the path.

The indexed method expresses a numerical "stepped" value path to the parent node, i.e. path=indexed:1/2/3. This example could be expressed as: 'The third child node of the second child node of the first child node of the xml root'.

The xpath method is an XPath 'expression' that evaluates to a collection of nodes in the XML tree. In this case, the iterated nodes are those of the resulting 'collection' of nodes. This is a bit different from the 'named' and 'indexed' method in that the collection of node are not the 'child' nodes of a given 'parent' node. This is the most powerful method for selecting XML nodes. There are several online 'xpath' tutorials that you can visit that will help you develop your XPath skills.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
[xmlnodes ref=xml_var1]
   [name] = [value]<br>
[/xmlnodes]copy

Results: This example finds the first node or the root of the XML document.
CATALOG =
The node named 'CATALOG' is the only child node from the root of the XML file. Notice that the 'value' is empty. This is because the 'CATALOG' node has no value, and is actually a 'container' node for other XML nodes. A 'value' will only be displayed for a 'leaf' XML node.

Expanding on the method of a named path to delve deeper into the file.
Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
[xmlnodes ref=xml_var1&path=named:Catalog]
  [name] =  [value]<br>
[/xmlnodes]copy

Results: All the names of the child nodes of the parent 'CATALOG' are displayed. Again, none of the resulting child nodes contain a value as they are all 'container' nodes.
CD=
CD=
CD=
CD=
CD=

[xmlnodes] contexts can be embedded within [xmlnodes] contexts. This method will iterate the child nodes of all the 'CD' nodes of the example file.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
[xmlnodes ref=xml_var1&path=named:Catalog]
  <b>[name] - [index]</b><br>
  [xmlnodes]
    [name] = [value]<br>
  [/xmlnodes]<br>
[/xmlnodes]copy

Results: (only the first 4 are displayed here, there are may more in the file) Note that the 'inner' xmlnodes context did not need a 'ref' parameter. This is because the inner xmlnodes context inherited the outer xmlnodes' current iterated node. Also notice that the inner xmlnodes context did not use a 'path' parameter. So it uses the 'root' path of the outer xmlnodes' current iterated node. As with most 'iterative' WebDNA contexts, the [index] tag resolves to the current iteration 'count'.
CD - 1
  TITLE = Empire Burlesque
  ARTIST = Bob Dylan
  COUNTRY = USA
  COMPANY = Columbia
  PRICE = 10.90
  YEAR = 1985
CD - 2
  TITLE = Hide your heart
  ARTIST = Bonnie Tylor
  COUNTRY = UK
  COMPANY = CBS Records
  PRICE = 9.90
  YEAR = 1988
CD - 3
  TITLE = Greatest Hits
  ARTIST = Dolly Parton
  COUNTRY = USA
  COMPANY = RCA
  PRICE = 9.90
  YEAR = 1982
CD - 4
  TITLE = Still got the blues
  ARTIST = Gary More
  COUNTRY = UK
  COMPANY = Virgin records
  PRICE = 10.20
  YEAR = 1990

With a minor change to the 'path' parameter, we can retrieve all the child nodes of the fifth 'CD' node of example-file.xml, still using the named method.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
[xmlnodes ref=xml_var1&path=named:Catalog/CD(5)]
  [name] = [value]
[/xmlnodes]
copy

Results:
TITLE = Eros
ARTIST = Eros Ramazzotti
COUNTRY = EU
COMPANY = BMG
PRICE = 9.90
YEAR = 1997

Once again using the named method the results can be filtered to display only the 'TITLE' node of the fifth 'CD' node of example-file.xml using the name parameter.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
[xmlnodes ref=xml_var1&path=named:Catalog/CD(5)&name=TITLE]
  [name] = [value]
[/xmlnodes]copy

Results:
TITLE = Eros

Further filtering is possible using the name and exact parameters, we can filter the results to display only those nodes, of the fifth 'CD' node, where the node name matches a given sub-string, 'CO' of example-file.xml

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
[xmlnodes ref=xml_var1&path=named:Catalog/CD(5)&name=CO&exact=F]
  [name] = [value]
[/xmlnodes]copy

Results: Both node names start with CO, so that satisfies the exact=F
COUNTRY = EU
COMPANY = BMG

The 'path' parameter is used to locate the node. As with the [xmlnodes] context, the 'path' parameter has three modes; named, indexed, and xpath.

[xmlnode] can also be used to persist a 'pointer' to a specific node. This reference can then be used in subsequent calls to other XML contexts.

From example-file.xml the [xmlnode] context can be used to retrieve the TITLE information of the third CD node.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
[xmlnode ref=xml_var1&path=indexed:1/3/1]
  [name] = [value]
[/xmlnode]copy

Results: Note that that the indexed path method is used. This assumes that the desired XML node is already known.
TITLE=Greatest Hits

If the XML has been parsed previously on the page then there is no need to parse it again if performing subsequent operations on the same XML data. In the example below the var 'xml_var1' is referenced as previously parsed XML data. Using [xmlnode] to get all of the XML data within the node, the XML data within that node can be accessed using [xmlnodes].

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlnode ref=xml_var1&path=indexed:1/3&var=xml_CD3][/xmlnode]
[xmlnodes ref=xml_CD3]
  [name] = [value]
[/xmlnodes]copy

Results: The content of the 3rd node is stored in memory by WebDNA with the reference 'xml_CD3', this reference is then used to get the content of the referenced node.
TITLE = Greatest Hits
ARTIST = Dolly Parton
COUNTRY = USA
COMPANY = RCA
PRICE = 9.90
YEAR = 1982

The path parameter is used to locate the node. As with the [xmlnodes] context and the [xmlnode] context, the path parameter has three modes; named, indexed and xpath.

The [xmlnodesattributes] context is used to retrieve the attributes of an XML node, the attributes are the parameters of the XML node container.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

<b>Parse the xml file:</b><br>
[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
<b>Get the contents of the indexed node:</b><br>
[xmlnode ref=xml_var1&path=indexed:1/1]
  [content]
[/xmlnode]<br>
<b>Display the attributes of the node:</b><br>
[xmlnodeattributes ref=xml_var1&path=indexed:1/1]
  [name] = [value]<br>
[/xmlnodeattributes]copy

Results:
Parse the xml file:
Get the contents of the indexed node:
<CD status="instock" id="123">
<TITLE>Empire Burlesque</TITLE>
<ARTIST>Bob Dylan</ARTIST>
<COUNTRY>USA</COUNTRY>
<COMPANY>Columbia</COMPANY>
<PRICE>10.90</PRICE>
<YEAR>1985</YEAR>
</CD>
Display the attributes of the node:
id = 123
status = instock

To simplify the code, place the [xmlnodesattributes] context 'inside' of the [xmlnode] context. In this case, the 'path' or 'ref' parameters are not required [xmlnodesattributes], as the 'implied' XML node in the outer [xmlnode] context is used.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xmlparse var=xml_var1][include file=example-file.xml][/xmlparse]
[xmlnode ref=xml_var1&path=indexed:1/1]
  [xmlnodeattributes]
    [name] = [value]<br>
  [/xmlnodeattributes]
[/xmlnode]copy

Results:
id = 123
status = instock

These new contexts enable the WebDNA programmer to compile and apply XSL style sheets to XML data, allowing the programmer to query and render XML data as they see fit.

Example WebDNA code:

[xsl var=xsl_var1]
  <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:template match="/">
      <html>
        <body>
          <h2>My CD Collection</h2>
          <table border="1">
            <tr bgcolor="#9acd32">
              <th>Title</th>
              <th>Artist</th>
            </tr>
            <xsl:for-each select="CATALOG/CD">
              <tr>
                <td><xsl:value-of select="TITLE"/></td>
                <td><xsl:value-of select="ARTIST"/></td>
              </tr>
            </xsl:for-each>
          </table>
        </body>
      </html>
    </xsl:template>
  </xsl:stylesheet>
[/xsl]copy

Results: WebDNA 'saves' this compiled instance as an internal variable in memory named 'xsl_var1'. This saved instance can then be referenced when using the [xslt] context on the same page.

The [xsl] styles can also be called from a file.

Example WebDNA code:
This example uses an example file that you can view/download here example-xml-styles.xsl

[xsl var=xsl_var1][include file=example-xml-styles.xsl][/xsl]copy

Select all the 'CD' nodes in example-file.xml and transform the results into an HTML table, with the 'text' data of each CD node tree displayed in the table rows.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xsl var=xsl_var1]
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:template match="/">
    <html>
      <body>
        <h2>My CD Collection</h2>
        <table border="1">
          <tr bgcolor="#9acd32">
            <th>Title</th>
            <th>Artist</th>
          </tr>
          <xsl:for-each select="CATALOG/CD">
            <tr>
              <td><xsl:value-of select="TITLE"/></td>
              <td><xsl:value-of select="ARTIST"/></td>
            </tr>
          </xsl:for-each>
        </table>
      </body>
    </html>
  </xsl:template>
</xsl:stylesheet>
[/xsl]
[xslt xslref=xsl_var1][include file=example-file.xml][/xslt]copy

Or using a link to an external XML stylesheet.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml and the external style sheet example-xml-styles.inc

[xslt xslsource=example-xml-styles.xsl&xmlsource=example-file.xml][/xslt]copy

Results: Using either method, the results are the same

My CD Collection

Title	Artist
Empire Burlesque	Bob Dylan
Hide your heart	Bonnie Tylor
Greatest Hits	Dolly Parton
Still got the blues	Gary More
Eros	Eros Ramazzotti
One night only	Bee Gees
Sylvias Mother	Dr.Hook
Maggie May	Rod Stewart
Romanza	Andrea Bocelli
When a man loves a woman	Percy Sledge
Black angel	Savage Rose
1999 Grammy Nominees	Many
For the good times	Kenny Rogers
Big Willie style	Will Smith
Tupelo Honey	Van Morrison
Soulsville	Jorn Hoel
The very best of	Cat Stevens
Stop	Sam Brown
Bridge of Spies	T`Pau
Private Dancer	Tina Turner
Midt om natten	Kim Larsen
Pavarotti Gala Concert	Luciano Pavarotti
The dock of the bay	Otis Redding
Picture book	Simply Red
Red	The Communards
Unchain my heart	Joe Cocker

Download some further XSL styling examples: more-example-xml-styles.xsl

Appending XML to a WebDNA database

This example uses XSLT to generate WebDNA [append] code to append the XML data to a WebDNA database.

Example WebDNA code:
This example uses an example file that you can view/download here example-file.xml

[xsl var=xsl_var1][!]
[/!]%5Breplace db=music.db[url]&[/url]eqTITLEdata=[url]&[/url]append=T%5D[!]
[/!]TITLE=[url]&[/url][!]
[/!]ARTIST=
%5B/replace%5D
[/xsl]
[text]result=[unurl][xslt xslref=xsl_var1][include file=example-file.xml][/xslt][/unurl][/text]copy

Results: The [text] variable 'results' contains the following:
[replace db=music.db&eqTITLEdata=Empire Burlesque&append=T]TITLE=Empire Burlesque&ARTIST=Bob Dylan[/replace]
[replace db=music.db&eqTITLEdata=Hide your heart&append=T]TITLE=Hide your heart&ARTIST=Bonnie Tylor[/replace]
[replace db=music.db&eqTITLEdata=Greatest Hits&append=T]TITLE=Greatest Hits&ARTIST=Dolly Parton[/replace]
[replace db=music.db&eqTITLEdata=Still got the blues&append=T]TITLE=Still got the blues&ARTIST=Gary More[/replace]
[replace db=music.db&eqTITLEdata=Eros&append=T]TITLE=Eros&ARTIST=Eros Ramazzotti[/replace]
[replace db=music.db&eqTITLEdata=One night only&append=T]TITLE=One night only&ARTIST=Bee Gees[/replace]
[replace db=music.db&eqTITLEdata=Sylvias Mother&append=T]TITLE=Sylvias Mother&ARTIST=Dr.Hook[/replace]
[replace db=music.db&eqTITLEdata=Maggie May&append=T]TITLE=Maggie May&ARTIST=Rod Stewart[/replace]
[replace db=music.db&eqTITLEdata=Romanza&append=T]TITLE=Romanza&ARTIST=Andrea Bocelli[/replace]
[replace db=music.db&eqTITLEdata=When a man loves a woman&append=T]TITLE=When a man loves a woman&ARTIST=Percy Sledge[/replace]
[replace db=music.db&eqTITLEdata=Black angel&append=T]TITLE=Black angel&ARTIST=Savage Rose[/replace]
[replace db=music.db&eqTITLEdata=1999 Grammy Nominees&append=T]TITLE=1999 Grammy Nominees&ARTIST=Many[/replace]
[replace db=music.db&eqTITLEdata=For the good times&append=T]TITLE=For the good times&ARTIST=Kenny Rogers[/replace]
[replace db=music.db&eqTITLEdata=Big Willie style&append=T]TITLE=Big Willie style&ARTIST=Will Smith[/replace]
[replace db=music.db&eqTITLEdata=Tupelo Honey&append=T]TITLE=Tupelo Honey&ARTIST=Van Morrison[/replace]
[replace db=music.db&eqTITLEdata=Soulsville&append=T]TITLE=Soulsville&ARTIST=Jorn Hoel[/replace]
[replace db=music.db&eqTITLEdata=The very best of&append=T]TITLE=The very best of&ARTIST=Cat Stevens[/replace]
[replace db=music.db&eqTITLEdata=Stop&append=T]TITLE=Stop&ARTIST=Sam Brown[/replace]
[replace db=music.db&eqTITLEdata=Bridge of Spies&append=T]TITLE=Bridge of Spies&ARTIST=T`Pau[/replace]
[replace db=music.db&eqTITLEdata=Private Dancer&append=T]TITLE=Private Dancer&ARTIST=Tina Turner[/replace]
[replace db=music.db&eqTITLEdata=Midt om natten&append=T]TITLE=Midt om natten&ARTIST=Kim Larsen[/replace]
[replace db=music.db&eqTITLEdata=Pavarotti Gala Concert&append=T]TITLE=Pavarotti Gala Concert&ARTIST=Luciano Pavarotti[/replace]
[replace db=music.db&eqTITLEdata=The dock of the bay&append=T]TITLE=The dock of the bay&ARTIST=Otis Redding[/replace]
[replace db=music.db&eqTITLEdata=Picture book&append=T]TITLE=Picture book&ARTIST=Simply Red[/replace]
[replace db=music.db&eqTITLEdata=Red&append=T]TITLE=Red&ARTIST=The Communards[/replace]
[replace db=music.db&eqTITLEdata=Unchain my heart&append=T]TITLE=Unchain my heart&ARTIST=Joe Cocker[/replace]

These results are then able to be 'appended' to the music.db

Example WebDNA code:

[interpret]
  [result]
[/interpret]copy