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Complete VBScript Reference
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)
| Parameter | Description |
|---|---|
| expression | Required. An expression |
Example
Example
<script type="text/vbscript">
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))
</script>
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))
</script>
The output of the code above will be:
False
False
False
True
False
False
True
Try it yourself »
Complete VBScript Reference
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