The difference between == and === in js

== and === in JavaScript are equality comparison operators. == (loose equality) performs type conversion and allows comparison of data of different types, while === (strict equality) does not perform type conversion and only compares whether types and values ​​are equal, allowing only comparison of data of the same type.

The difference between == and === in JavaScript

Question: In JavaScript What is the difference between == and ===?

Detailed answer:

== and === are equality comparison operators in JavaScript, but they differ in the different factors that are considered when comparing data. .

== (Loose Equality)

• Convert the left and right operands to the same type before comparing them.
• Allows type conversion, such as converting a string to a number.
• Can compare different types of data, such as strings and numbers.

=== (strict equality)

• No type conversion is performed.
• Compare whether the types and values ​​of the operands are equal.
• Only data of the same type is allowed to be compared.

Example:

• 1 == "1" // true (loose equality converts the string "1" to the number 1)
• 1 === "1" // false (strict equality considers type differences)

The specific comparison behavior is as follows:

##Numbers and numbersEqualEqualStrings and stringsEqualEqualBoolean values ​​and Boolean valuesEqualEqualNaN and NaNEqualEqualnull and nullEqualEqualundefined and undefinedEqualEqualNumbers and stringsNot equalEqualBoolean values ​​and numbersNot equalEqualBoolean values ​​and stringsNot equalEqualnull and undefinedEqualEqualObject and objectPoints to the same objectPoints to the same object

Comparison types	==	===

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