The IsNull Function

The IsNull function returns a Boolean value that indicates whether a specified expression contains no valid data (Null). It returns True if expression is Null; otherwise, it returns False.

Syntax

IsNull(expression)

Example 1

dim x
document.write(IsNull(x) & "<br />")
x=10
document.write(IsNull(x) & "<br />")
x=Empty
document.write(IsNull(x) & "<br />")
x=Null
document.write(IsNull(x))

Output:

False
False
False
True

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