ISNULL function  

Purpose

Determine if a string is null (zero-length).

Syntax

ResultVar& = ISNULL(StrgExpr)

Remarks

The StrgExpr is examined to determine whether it is null (has zero characters).  The value true (-1) is returned if the StrgExpr is null, or false (0) if it contains characters.

The complementary function is ISNOTNULL.

See also

ISNOTNULL