How to compare null values in vba

Free Excel Course. Login details for this Free course will be emailed to you. Article by Jeevan A Y. Please select the batch. Cookies help us provide, protect and improve our products and services. Returns a Boolean value that indicates whether an expression contains no valid data Null. The required expression argument is a Variant containing a numeric expression or a string expression. If expression consists of more than one variable , Null in any constituent variable causes True to be returned for the entire expression.

The Null value indicates that the Variant contains no valid data. Null is not the same as Empty , which indicates that a variable has not yet been initialized.

It is also not the same as a zero-length string "" , which is sometimes referred to as a null string. Use the IsNull function to determine whether an expression contains a Null value. The opposite is possible with not obj is nothing not with obj is not nothing :. Also, the function typeName obj returns the string "Nothing" if obj is nothing. Thus, empty signals that the variable is not initialized. Such a variable evaluates to 0 zero in numeric and to "" empty string in string context.

Therefore, a variable that is not a variant such as a long cannot be empty but empty can be assigned to such a variable. In order to test whether a variant is empty, the special function isEmpty … can be used.