Excel VBA IsNull Function

VBA IsNull Function: The IsNull function in VBA returns a Boolean, indicating whether a supplied expression is Null.

Syntax

IsNull (Expression)

Parameter

Expression (required)- This parameter represents the name of the argument that you want to check.

Return

This function returns a Boolean value True if the specified expression is null else it returns False if the argument has been supplied.

Example 1

Sub IsNull_Example1()
 Dim var
 Dim is_Null As Boolean
 var = 15
 is_Null = isNull(var)
 ' The isNull1 variable returns a boolean value False.
 Cells(1, 1).Value = ("The isNull function returns ")
 Cells(1, 2).Value = is_Null
 End Sub 

Output

The isNull function returns

FALSE

Example 2

Sub IsNull_Example2()
 Dim var
 Dim is_Null As Boolean
 'passing var as Null
 var = Null
 is_Null = isNull(var)
 ' The isNull1 variable returns a boolean value TRUE.
 Cells(1, 1).Value = ("The isNull function returns ")
 Cells(1, 2).Value = is_Null
 End Sub 

Output

The isNull function returns

TRUE

Example 3

Sub IsNull_Example3()
 Dim var
 Dim is_Null As Boolean
 'var will be initialized with default value
 is_Null = isNull(var)
 ' The isNull1 variable returns a boolean value False.
 Cells(1, 1).Value = ("The isNull function returns ")
 Cells(1, 2).Value = is_Null
 End Sub 

Output

The isNull function returns

FALSE