ISREF

Tests if the argument is a reference to a cell or range of cells.

Syntax:

ISREF(value)

Returns TRUE if value is a reference to a cell or range of cells and FALSE otherwise.

Example:

ISREF(C5)

returns TRUE, because C5 refers to a cell.

ISREF(A1:B3)

returns TRUE, because A1:B3 refers to a range of cells.

ISREF("A5")

returns FALSE, because "A5" is text, not a cell reference.

ISREF(NA())

returns FALSE, because NA() is an error, not a cell reference.

ISREF(A9999999)

returns FALSE, because cell A9999999 does not exist.

ISREF(range1)

where range1 is the named range A1:B3, returns TRUE.

ISREF(range2)

where range2 is not defined, returns the #NAME? error

ISREF(INDIRECT(C1))

where cell C1 contains the text "D1", returns TRUE, because INDIRECT returns a reference.

Application:

A good application of ISREF is in a validation or error-checking formula. Imagine you have a spreadsheet for a simple inventory system where a user needs to enter either the quantity of an item or a reference to a cell containing the quantity. You want to make sure the input is correct and provide a helpful message if it's not.

Here's a table-based example:

Inventory Tracking Sheet

	Item	Quantity	Valid Input?	Notes
	A	B	C	D
1	Apples	100	TRUE	User entered a number
2	Oranges	50	TRUE	User entered a number
3	Grapes	N/A	FALSE	User entered a text string
4	Bananas	#REF!	FALSE	User entered a reference to a deleted cell

The result will be:

C1: TRUE (because B1 is a number)
C2: TRUE (because B2 is a number)
C3: FALSE (because B3 is text)
C4: TRUE (because B4 is an error reference, which ISREF correctly identifies as a reference)

This example demonstrates how ISREF can be used to validate if an input is a reference, even if that reference is broken. In this case, ISREF is not needed for the first two rows but is essential for correctly validating the input in row 4.