Many times, we come across a function we want our Crystal Reports software to provide--but it doesn't. This doesn't mean there's something wrong with Crystal Reports.

It simply means you need the program to do something the program was designed to do. Crystal Reports programmers anticipated this, early in the development of the program and provided a way to get over that barrier. They could have chosen to bloat the program with every conceivable function (so few could afford it or even manage to load it into their system), but instead they chose to provide Crystal Reports with the ability to accept User Function Libraries.

What is a User Function Library (UFL)? Essentially, it's a piece of code that plugs into Crystal Reports to expand its functionality. Most people do not need every UFL available. But, nearly everyone needs at least one or two UFLs.

What does it take to write a good UFL? Here are some of the requirements:

• A solid knowledge of a programming language such as Visual Basic.

• A solid understanding of how to write DLLs.

• A solid understanding of how to write DLLs that "play nice" with other programs.

• An understanding of the Crystal Reports Equations Editor and Function Tree.

• Knowledge of the file-naming conventions that allow UFLs to work properly and to cohabitate with other coding.

• Knowledge of how to declare and create items inside the class  modules.

• Understanding of, and adherence to, Crystal Reports' UFL deployment requirements.

• The ability to test UFLs on various machines and across various test situations--both simulated and real.

• The ability to update the UFL when updating Crystal Reports.

• The time and patience to develop the UFL methodically, streamline its code, and test it properly.

Now, don't worry if you don't have all of requisite skills and resources. We have all of these and more, and thus they can fill the void for you (see below).

But where does a UFL go?

User Function Libraries are used inside a formula to add calculations that are not otherwise available. They show up as Functions in your Formula Editor and extra functions are usually displayed under Additional Functions.

We have developed some interesting functions, and there are some others available from Business Objects and other 3^rd party developers.

User Function Libraries first appeared in Crystal Reports 5, and were a DLL that was installed in the Windows\Crystal folder. This folder continues to work for all subsequent versions of Crystal Reports.

You can also install them in the Crystal Program folder. This varies from version to version since version 9.0. Crystal Reports 2008 installs into

C:\Program Files\Business Objects\BusinessObjects Enterprise 12.0\win32_x86

Some great UFLs

Below is a listing of available UFLs. Click the link or associated image for pricing and information on each one.

XML UFL for Crystal Reports
cViewIMAGE
cViewPICK
Registry Function Library for Crystal Reports
International Function Library for Crystal Reports
Disk File Output Function Library
Text Lookup Function Library for Crystal Reports
cViewMAIL
Mail Function Library for Crystal Reports
Mail Function (SMTP) for Crystal Reports