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Comparison Operators
Description
Returns a Boolean value indicating the result of the
comparison.
Syntax
expression1 comparisonoperator
expression2
The Comparison operator syntax
has these parts:
Remarks
When comparing strings, JScript
uses the Unicode character value of the string expression.
The following describes how the
different groups of operators behave depending on the types and values of
expression1 and expression2:
Relational (<, >, <=, >=)
-
Attempt to convert both
expression1 and expression2 into numbers.
-
If both expressions are
strings, do a lexicographical string comparison.
-
If either expression is
NaN,
return false.
-
Negative zero equals Positive
zero.
-
Negative Infinity is less than
everything including itself.
-
Positive Infinity is greater
than everything including itself.
Equality (==, !=)
-
If the types of the two
expressions are different, attempt to convert them to string, number, or
Boolean.
-
NaN is not equal to
anything including itself.
-
Negative zero equals positive
zero.
-
null equals both
null
and undefined.
-
Values are considered equal if
they are identical strings, numerically equivalent numbers, the same
object, identical Boolean values, or (if different types) they can be
coerced into one of these situations.
-
Every other comparison is
considered unequal.
Identity (===. !==)
These operators behave
identically to the equality operators except no type conversion is done,
and the types must be the same to be considered equal.
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