Difference between revisions of "ISSET()"

From Lianjapedia
Jump to: navigation, search
Line 24: Line 24:
 
[[Category:Memory Variables]]
 
[[Category:Memory Variables]]
 
[[Category:Memory Variables Functions]]
 
[[Category:Memory Variables Functions]]
 +
[[Category:Lianja VFP Extensions]]
 +
[[Category:VFP Function Extensions]]

Revision as of 07:24, 10 December 2012

Purpose

Function to check whether a variable exists

Syntax

ISSET(<variable name>)

See Also

DECLARE, DIMENSION, LOCAL, PARAMETERS, PRIVATE, PUBLIC, RELEASE, STORE, TYPE(), UNSET(), VARTYPE()

Description

The ISSET() function can be used to check whether a variable exists. ISSET() will return .T. (true) if the variable named <variable name> exists and .F. (false) if it does not exist. Variables can be formally declared (PUBLIC, PRIVATE etc.) or automatically created when they are assigned a value.

Example

if isset(m_var)
  // m_var exists
endif