DevGuru XSLT element xsl:number

ELEMENT: xsl:number

<xsl:number
  count="pattern"
  format="{ string }"
  from="pattern"
  grouping-separator="{ character }"
  grouping-size="{ number }"
  lang="{ languagecode }"
  letter-value={ "alphabetic" | "traditional" }
  level="any" | "multiple" | "single"
  value="expression"
>
</xsl:number>

The xsl:number element has two possible uses. It can determine the sequence number for the current node and it can format a number for display in the output.

The sequence number is the integer position of the current node in a source document (source tree). There are actually three ways that the sequence number can be determined and you can use the level attribute to choose which way.

The formatting process converts either the sequence number or the number provided by the value attribute to a string. By using various attributes of the xsl:number element, you can exert great control over the appearance of the formatted number in the output.

In comparison, the xsl:decimal-format element defines the symbols and characters used by the format-number function to convert numbers to strings.

This is a self-closing element and it cannot contain any child elements or any content.

count="pattern"

The optional count attribute dictates what nodes are to be counted. Only nodes that match the pattern are counted. The default is to count any node that matches the pattern of the current node.

format="{ string }"

The optional format attribute is set to an Attribute Value Template that dictates the output format for the number. You can use any the following choices:

Format	Output Sequence
1	1 2 3 4 ... 10 11 12 ...
01	01 02 03 04 ... 10 11 12 ...
a	a b c ... z aa ab ac ...
A	A B C ... Z AA AB AC ...
i	i ii iii iv v vi vii viii ix x ...
I	I II II IV V VI VII VIII IX X ...

For example, format="1.A.a. " would allow the appropriate paragraph to be numbered 6.C.b.

from="pattern"

The optional from attribute specifies a starting point from which the sequential counting will start. The nodes are matched to the pattern to find the starting point.

grouping-separator="{ character }"

The optional grouping-separator attribute is set to an Attribute Value Template or a character that dictates what character is to be used to separate groups of digits in the number being displayed in the output. White-space is permitted. The grouping-separator attribute is ignored if you do not also set the grouping-size attribute to the digit group size. The classic example is to use a comma to separate groups of three digits.

grouping-size="{ number }"

The optional grouping-size attribute is set to an Attribute Value Template or a number that dictates how many digits are in the groups that are being separated by the character specified in the grouping-separator attribute. The grouping-size attribute is ignored if you do not also use the grouping-separator attribute to specify a separator. The classic example are groups of three digits separated by a comma.

lang="{ languagecode }"

The optional lang attribute is set to an Attribute Value Template or a string that dictates the language code which in turn specifies the language alphabet to be used for the numbering. The default language is set by the operating system environment.

letter-value="{ alphabetic | traditional }"

The optional letter-value attribute is set to an Attribute Value Template that dictates whether the numbering sequence in the selected language is either alphabetic or traditional. Or it can be set directly to either one of the two permitted values. The primary example is Traditional Hebrew versus Alphabetic Hebrew. The default is alphabetic.

level="any" | "multiple" | "single"

The optional level attribute is set to an Attribute Value Template that controls how the sequence number is assigned. Or it can be set directly to one of the three permitted values. There are only three permitted procedures for determining a sequence number:

Level	Effect
single	The default value. All preceding nodes that match the target node pattern are counted. Limitations imposed by the from and count attributes are obeyed. The sequence starts at one. If the current target node has four preceding nodes, then the current target node will be given the sequence number of five.
multiple	First, a list is constructed of all ancestors of the current node. The list goes back to, but does not include, the ancestor that matches the optional from attribute pattern. Next, for each node in the list that matches the count pattern, the XSL processor maps how many preceding siblings of that node match the count pattern. This hierarchic position information is provided in a composite sequence number list.
any	Starting from the current node, the XSL processor counts how many nodes match the count attribute pattern. If a node specified in the optional from attribute is encountered, the counting process stops. The sequence number is the number of nodes counted. This can be zero, if the current node does not match the count pattern.

value="expression"

The optional value attribute is a user-provided number that is used in place of a sequence generated number. If the expression generates a real number, it will be rounded and converted to an integer. The default is to use a sequence number which is based upon the current node's position in the source document (source tree).

We use the DevGuru Staff List XML file for our example with the following header:
<?xml-stylesheet type="text/xsl" href="xslt_example_number.xsl"?>
and we name it: xslt_example_number.xml

Code for xslt_example_numbert.xsl:

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:template match="/">
<html>
<body>
<xsl:for-each select="devguru_staff/programmer">
<xsl:number value="position()" format="1. " />
<xsl:value-of select="name" />
<br />
</xsl:for-each>
</body>
</html>
</xsl:template>
</xsl:stylesheet>

Output:

Click to view output in separate window - requires Internet Explorer