Book Image

Programming Microsoft Dynamics NAV 2009

Book Image

Programming Microsoft Dynamics NAV 2009

Overview of this book

Microsoft Dynamics NAV is a well established Enterprise Resource Planning (ERP) application, part of the Microsoft Dynamics family. Dynamics NAV is installed worldwide, with well over one million users. Version 2009 contains many major new features and structures, requiring even experienced Dynamics NAV developers to refresh their NAV development knowledge. Renowned for its challenging learning curve, Dynamics NAV is a complex piece of software with a unique design structure. For developers learning to modify or enhance Dynamics NAV for vital business purposes, the task can sometimes be intimidating. This book is an in-depth step-by-step guide to programming NAV, designed to ease you through the complexities of NAV application development. You will learn the skills and develop the confidence to tackle your own critical NAV applications. This book will act as your experienced NAV programming mentor, helping you to become productive as a NAV developer much more quickly. NAV development is quite complex, with a steep learning curve. This book makes it easy for you. From basic NAV terminology and concept definitions, through the essential building blocks of NAV data structure and objects, you will gain an understanding of the fundamental underlying concepts of NAV. You will learn practical details about NAV object construction and the tools available, including table, page, and report design. You will learn how to use NAV's tools to effectively navigate through the various features of objects, including properties, triggers, and C/AL code, and receive practical guidance on ways to develop and test in the unique NAV C/SIDE development environment. Extensive guidance on software design for NAV is provided along with tips for efficient design of new NAV applications or enhancing existing applications. With its comprehensive collection of NAV information and distillation of years of NAV development experience, this book is not only designed to help you learn, but to act as a reference as well.
Table of Contents (18 chapters)
Programming Microsoft® Dynamics™ NAV 2009
Credits
About the Author
Acknowledgement
About the Reviewers
Foreword
Preface
Index

Computation and Validation utility functions


C/AL includes a number of utility functions designed to facilitate data computations and validation or initializing of field contents. The following are some of the Validation utility functions:

  • TESTFIELD

  • FIELDERROR

  • VALIDATE

  • ROUND

  • TODAY, TIME, and CURRENTDATETIME functions

  • WORKDATE functions

TESTFIELD

The TESTFIELD function is widely used in standard NAV code. With TESTFIELD, you can test a variable value and, if the test fails, issue an error message in a single statement. The syntax is as follows:

Record.TESTFIELD (Field, [Value] )

If a Value is specified and the field does not contain that value, an error condition is raised (that is, the process terminates) and the associated error message is issued. If no Value is specified, the condition evaluated is to compare the field contents to zero or blank. If no Value is specified and the field is zero or blank, then that is an error.

The advantage of TESTFIELD is ease of use and consistency...