Returns true if the value is null, and returns false otherwise, except as noted.

Syntax

isnull( value )

value: (Any Type) Value to check for null.

Returns

Boolean

Notes

Empty arrays return false when passed to the isnull() function.

The function will not work without a parameter. It is typically used to test whether a Process Variable contains a null value.

Examples

isnull(!userPV) returns true where userPV is a process variable of type User, which is null.

See Also

length(): Use the length() function instead when testing Multiple value variables.