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This article mainly introduces the relevant knowledge of "how to redefine variables in JavaScript". The editor shows you the operation process through an actual case. The method of operation is simple and fast, and it is practical. I hope this article "how to redefine variables in JavaScript" can help you solve the problem.

Redefine variables

Redeclaring variables using the var keyword can be problematic.

Redeclaring variables in a block also redeclares variables outside the block:

Case study

Var x = 10

/ / the output x here is 10

{

Var x = 2

/ / the output x here is 2.

}

/ / the output x here is 2.

The let keyword solves this problem because it is only valid within the code block {} where the let command is located.

Case study

Var x = 10

/ / the output x here is 10

{

Let x = 2

/ / the output x here is 2.

}

/ / the output x here is 10

That's all for "how to redefine variables in JavaScript". Thank you for reading. If you want to know more about the industry, you can follow the industry information channel. The editor will update different knowledge points for you every day.

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