Deprecated since JavaScript api32
This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
Determine if a given jsval is null.
Syntax
JSVAL_IS_NULL(v)
Description
JSVAL_IS_NULL(v) is true if v is JSVAL_NULL, which is the JavaScript null value.
(Note: JSVAL_IS_OBJECT(JSVAL_NULL)true.)
Example
The following code snippet illustrates how a JavaScript variable, MyItem, is conditionally tested in an if statement to see if it contains a null value.
if (JSVAL_IS_NULL(MyItem)) {
...
}