The difference between === and == in js

In JavaScript, the == operator performs a loose equality comparison (converting types and comparing values), while the === operator performs a strict equality comparison (directly comparing types and values). It is recommended to use the === operator to avoid unexpected results.

The difference between === and == in JavaScript

== and === operators are JavaScript Operator used to compare two values ​​for equality. Although they look similar, there are some key differences between them.

== (Loose Equality) The

== operator performs a loose equality comparison, which means it attempts to convert two values ​​to the same type, and then Check if they are equal. This can lead to unexpected results:

<code class="js">console.log(1 == "1"); // true
console.log([] == 0); // true
console.log(false == null); // false</code>

=== (Strict Equality) The

=== operator performs strict equality comparisons, which means it does not An attempt will be made to convert the value to the same type. Instead, it directly compares the type and value of the value itself:

<code class="js">console.log(1 === "1"); // false
console.log([] === 0); // false
console.log(false === null); // false</code>

Choose which operator to use

Which operator to use depends on what kind of comparison you wish to make:

• Loose Equality (==): Used when you want to check that two values ​​are equal in value, regardless of their data types.
• Strict Equality (===): Used when you want to check that two values ​​are equal in both type and value.

In general, it is recommended to use the === operator for equality comparisons because it avoids unexpected results from loose equality.

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