educative.io

What is the use and when to use valueOf()

Courses
,
#1

I want to know what is exactly the use of valueOf() and when valueOf() is used?

In the course, JavaScript in Detail, the explanation is: " The .valueOf() will extract the value of the target type from the object." and on MDN the explanation is: " JavaScript calls the valueOf method to convert an object to a primitive value. You rarely need to invoke the valueOf method yourself; JavaScript automatically invokes it when encountering an object where a primitive value is expected."

I’m still not sure what they mean. Do we use it or not use it as MDN says “You rarely need to invoke the valueOf method yourself; JavaScript automatically invokes it when encountering an object where a primitive value is expected.”

Kindly explain.

#2

Hey @Souvik_Kundu

Yes, what you explained is correct, but we can use valueOf within our code to convert a built-in object into a primitive value. When we create a custom object, we can override Object.prototype.valueOf() to call a custom method instead of the default Object method, which will return us the primitive data type(primitive value).

Shaheryaar Kamal | Technical Content Engineer

1 Like
#3

Thank you @Shaheryaar_Kamal