Should I use == or === In Javascript?

2018-06-06 05:35:46

This question already has an answer here:

Which equals operator (== vs ===) should be used in JavaScript comparisons? 50 answers

Difference between == and === in JavaScript [duplicate] 2 answers

Using == compares only the values, === compares the type of the variable also.

1 == 1 -> true
1 == "1" -> true
1 === 1 -> true
1 === "1" -> false, because 1 is an integer and "1" is a string.

You need === if you have to determine if a function returns 0 or false, as 0 == false is true but 0 === false is false.

It really depends on the situation. It's usually recommended to use === because in most cases that's the right choice.

== means Similar while
=== means Equal. Meaning it takes object type in consideration.

Example

'1' == 1 is true

1 == 1 is true

'1' === 1 is false

1 === 1 is true

When using == it doesn't matter if 1 is a Number or a String.

http://www.w3schools.com/js/js_comparisons.asp

== is equal to || x==8 equals false

=== is exactly equal to (value and type) || x==="5" false

meaning that 5==="5" false; and 5===5 true

After all, it depends on which type of comparison you want.

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