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IsEmpty Function


This standard VB function is used to determine whether a variable of data type variant has been initialized.

Syntax

IsEmpty(expression)

Argument
Description
expression
Any expression containing a variable of data type variant

Returns

-1 (TRUE) if a variant has been initialized; 0 (FALSE) otherwise.

Usage

IsEmpty returns -1 (TRUE) if the variant is of vartype 0 (empty). Any newly defined variant defaults to being of Empty type, to signify that it contains no initialized data. An Empty variant converts to zero when used in a numeric expression, or an empty string ("") in a string expression.

Example

This example prompts for a series of test scores and uses IsEmpty to determine whether the maximum allowable limit has been hit. (IsEmpty determines when to exit the Do...Loop.)

Sub Button_Click
   Dim arrayvar(10)
   Dim x as Integer
   Dim tscore as Single
   Dim total as Integer
   x = 1
   Do
      tscore = 88
      arrayvar(x) = tscore
      x = x + 1
   Loop Until IsEmpty(arrayvar(10)) <> -1
   total = x-1
   msgtext = "You entered: " & Chr(10)
   For x = 1 to total
       msgtext = msgtext & Chr(10) & arrayvar(x)
      Next x
End Sub

See Also

IsDate Function
IsNull Function
IsNumeric Function
VarType Function


 Siebel VB Language Reference
 Published: 18 June 2003