[PREFIX-change][condition] ... [/condition] TEXT [/PREFIX-change]
Sets up a breaking sequence that occurs when the contents of [condition] [/condition] change. The most common one is a category break to nest or place headers.
The region is only output when a field or other repeating value between [condition] and [/condition] changes its value. This allows indented lists similar to database reports to be easily formatted. The repeating value must be a tag interpolated in the search process, such as [PREFIX-field] or [PREFIX-field database field]. If you need access to ITL tags, you can use [PREFIX-calc] with a $Tag-foo()> call.
Of course, this will only work as you expect when the search results are properly sorted.
The value to be tested is contained within a [condition]value[/condition] tag pair. The [PREFIX-change] tag also processes an [else] [/else] pair for output when the value does not change.
Here is a simple example for a search list that has a field category and subcategory associated with each item:
<TABLE> <TR><TH>Category</TH><TH>Subcategory</TH><TH>Product</TH></TR> [search-list] <TR> <TD> [item-change cat] [condition][item-field category][/condition] [item-field category] [else] [/else] [/item-change cat] </TD> <TD> [item-change sub] [condition][item-field subcategory][/condition] [item-field subcategory] [else] [/else] [/item-change sub] </TD> <TD> [item-field name] </TD> [/search-list] </TABLE>
The above should put out a table that only shows the category and subcategory once, while showing the name for every product. (The will prevent blanked table cells if you use a border.)