Difference between revisions of "ISSET()"

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[[Category:Documentation]]
 
[[Category:Documentation]]
 
[[Category:Functions]]
 
[[Category:Functions]]
[[Category:Memory Variables]]
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[[Category:Declaring Variables and Arrays]]
[[Category:Memory Variables Functions]]
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[[Category:Lianja VFP Extensions]]
 
[[Category:Lianja VFP Extensions]]
 
[[Category:VFP Function Extensions]]
 
[[Category:VFP Function Extensions]]

Revision as of 07:32, 4 February 2013

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