March 2000
Intermediate to advanced
576 pages
18h 13m
English
Content preview from Delphi in a Nutshell
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Name
Unassigned Variable
Syntax
var Unassigned: Variant;
Description
The Unassigned variable is a
Variant value that represents an uninitialized
variable. Delphi automatically initializes every
Variant variable to Unassigned.
If you attempt to use an Unassigned value in an
expression, Delphi reports runtime error 16
(EVariantError).
Tips and Tricks
Calling
VarClearis the same as assigningUnassignedto aVariantvariable.VarIsEmptyreturns True forUnassigned.
See Also
| Null Variable, VarClear Procedure, Variant Type, VarIsEmpty Function |
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