Crystal Reports:
User Function Libraries (UFLs) That Remember State
User Function Libraries (UFL) are
supposed to be stateless. That
means a UFL starts with some values, does all the processing required,
and then finishes its work. The next run of
the formula doesn't remember the values from the previous run
However, you can write a UFL that
does remember state, and you can use a series of functions inside formulas
to build disk files, write XML documents, send email to an SMTP server,
etc. We have several of these already written and available from our Web
site.
See the menu at left, or click here:
http://www.crystalkeen.com/crystalreporttools/ufls/
An occasional problem occurs with
UFLs. It appears that the
UFL is processed more than once, but only every now and then. Discussions with CD revealed that this is because the section is
processed, formatted, and then checked to see if it will fit on the bottom
of the page.
If it doesn't
fit, the page footer and header are processed. Then, section is reprocessed for the top of the new page.
To remove this problem do the
following:
1.
Write the report that uses your UFL functions in formulas.
2. Create a section above the
section where you do all the work, Details (a). This section must have a height, and can’t be suppressed or set
to Underlay. Using Underlay,
Suppress, or Suppress Blank Section on this section all cause duplicate
records.
3. Create a set of formulas as
follows:
Reset Counter:
Place in RH and PF sections
WhilePrintingRecords;
global numbervar c:=0
New Line: Place in the Details (a)
section.
This can be formatted with “Suppress”
WhilePrintingRecords;
global numbervar c:= c + 1
4. Set a conditional “New Page
After” on Details (a)
WhilePrintingRecords;
global numbervar c;
c >= 60
Some great UFLs
Below is a listing of some very useful UFLs.
Click the link or associated image for pricing and information on each
one.
Intrigued? Here's some info on the
GRID UFL.
Export structured data to Excel or another application, the
smart way. Grid UFL provides you the proper control of your Crystal Reports
Export. The ability to export your reports to another application or format is
one of the really useful features of Crystal Reports. But when you do this, you
run into the limitations of both Crystal Reports and the other application. Grid
UFL helps you overcome those limitations.
A really useful UFL:
Grid UFL allows you to treat your saved data as a Grid. To do this, you use the
GridCellClear (rows,cols) to declare a work area of a predetermined size. This
formula should normally be in your report header section. Then use other
formulas in your group and details section to save values in the grid.
You can use GridCellLoadRawValue (row, col, value) to store a value in the
working area. You could also use GridCellLoadDelimitedValue(row, col, value,
delimiter) to automatically put quote marks or some other field delimiter around
the value.
You can save it all to the disk file with GridCellSave(Filename,Separator). Use
a comma, tab character or any other ASCII value to separate each value on each
line of your disk file.
Think of the possibilities. Grid UFL opens an enormous number of them.
This article is copyrighted by
Crystalkeen, Mindconnection, and Chelsea Technologies Ltd. It may be
freely copied and distributed as long as the original copyright is
displayed and no modifications are made to this material. Extracts are
permitted. The names Crystal Reports and Seagate Info are trademarks owned
by Business Objects.
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