Working with Dates
If the source document contains nodes that take date values, using the xs:date or xs:dateTime datatypes in the underlying XML Schema makes available the powerful date and time manipulation features of XPath 2.0/3.0 (see examples below). StyleVision supports the xs:date or xs:dateTime datatypes by providing a wide range of date formatting possibilities via the Input Formatting feature.
| Note: | Date and time data cannot be manipulated with XPath 1.0. However, with XPath 1.0 you can still use Input Formatting to provide date formatting. |
Date calculations with XPath 2.0
Data involving dates can be manipulated with XPath 2.0 expressions in Auto-Calculations. Given below are a few examples of what can be achieved with XPath 2.0 expressions.
•The XPath 2.0 functions current-date() and current-dateTime() can be used to obtain the current date and date-time, respectively.
•Dates can be subtracted. For example: current-date() - DueDate would return an xdt:dayTimeDuration value; for example, something like P24D, which indicates a positive difference of 24 days.
•Time units can be extracted from durations using XPath 2.0 functions. For example: days-from-duration(xdt:dayTimeDuration('P24D')) would return the integer 24.
Here is an XPath 2.0 expression in an Auto-Calculation. It calculates a 4% annual interest on an overdue amount on a per-day basis and returns the sum of the principal amount and the accumulated interest:
if (current-date() gt DueDate)
then (round-half-to-even(InvoiceAmount +
(InvoiceAmount*0.04 div 360 *
days-from-duration((current-date() - DueDate))), 2))
else InvoiceAmount
Such a calculation would be possible with XPath 2.0 only if the DueDate element were defined to be of a date type such as xs:date and the content of the element is entered in its lexically correct form, that is, YYYY-MM-DD[±HH:MM], where the timezone component (prefixed by ±) is optional.