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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)
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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 a null 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
Related Topics
IsDate Function IsNull Function IsNumeric Function VarType Function
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