# <es:isNull> Tag

The <es:isNull> tag is used to check if a value is null. In the case of a String, the <es:isNull> tag is used to check if the String is null or is empty (zero length). An empty string is null.

## Syntax

<tagName attribute="value" />

## Attributes

item

Required (Object) - The variable to evaluate.

## Example

The following example prints a message if the value is null.

    <es:isNull item="<%=value%>">
    Error: the value is null.
    </es:isNull>

Related Topics

<es:notNull> Tag