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Siebel VB Language Reference > VB Language Reference > IsNull FunctionThis standard VB function is used to determine whether a variant variable has the Null value. SyntaxReturns-1 (TRUE) if a variant expression contains the Null value, 0 (FALSE) otherwise. UsageNull variants have no associated data and serve only to represent invalid or ambiguous results. Null is not the same as Empty, which indicates that a variant has not yet been initialized. ExampleThis example asks for ten test score values and calculates the average. If any score is negative, the value is set to Null. Then IsNull is used to reduce the total count of scores (originally 10) to just those with positive values before calculating the average. Sub Button_Click See AlsoIsDate Function |
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