null
The JavaScript keyword
null
is a special value that indicates no value.
null
is usually considered to be a special value
of object type -- a value that represents no object.
null
is a unique value, distinct from all other
values. When a variable holds the value
null
, you know that it does not contain a valid
object, array, number, string, or boolean value.[9]
[9]
C and C++ programmers should
note that null
in JavaScript is not the same as
0
, as it is in those languages. In certain
circumstances null
is converted to
0
, but the two are not equivalent.
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