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This article introduces the relevant knowledge of "what are the false values in Javascript". In the operation of actual cases, many people will encounter such a dilemma, so let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

When a condition is involved, javascript will use the call type to force or implicitly convert a value from one data type to another to evaluate anything in the condition as true (evaluated as true) or false (evaluated as false).

So needless to say, here are six types that are considered to be fake:

Keyword false

Original value undefined

Original value null

Empty string (', ")

Global property NaN

The number 0, such as 0.0,-0, or 0n

So what is true? It's simple, too, and if it's not in the list above, it's true! In other words, as long as it is not fake, it is true. For example, although empty arrays ([]) or similar empty objects ({}) may seem wrong at first glance, they are actually true because they are not in the list above!

One way I like to check the authenticity of a value is to use the double explosion operator! (or the double negative operator also applies)

You can test this in the browser console:

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