Object.is()
Object.is() is used to check whether two values are same or not.
Two values are same when they have the following criteria.
- Either both the values are undefined or null .
- Either both are true or false.
- Both strings should be of same length, same characters and in same order.
- The polarities of both the values should be equal.
- Both the values can be NaN and should be equal.
syntax
Object.is(val1, val2);
It accepts two parameters and scrutinize whether they are equal or not. If equal gives out true as output else false as output.
There is a small difference between Object.is() and "==" that is when comparing +0 and -0, the former results false whereas the latter results true. From this we can conclude that the method Object.is() scrutinizes even polarity.
Example
<html>
<body>
<script>
// comparing strings with same characters and same order
var val = Object.is("tutorialspoint", "tutorialspoint")
document.write(val);
document.write("</br>");
// comparing polarity
var pol = Object.is(-0, +0)
document.write(pol);
document.write("</br>");
//comparing unequal strings
var uneq = Object.is("tutorialspoint!", "tutorialspoint")
document.write(uneq);
document.write("</br>");
// comparing objects
var obj = Object.is( {object : 1}, {object : 2})
document.write(obj);
</script>
</body>
</html>Output
true false false false