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

Record.TESTFIELD (Field, [Value] )

If a Value is specified and the field does not contain that value, the process terminates with an error condition and the error message is issued.

If no Value is specified, the field contents are checked for values of zero or blank. If the field is zero or blank, then that an error message is issued.

The advantage of TESTFIELD is the ease of use and consistency in the code and the message displayed. The disadvantage is that the error message is not as informative as we might provide as a careful developer.

The following screenshot of TESTFIELD usage is from Table 18 – Customer...