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This article will explain in detail how to use JavaScript! The editor thinks it is practical to convert variables into Boolean types, so I share it with you as a reference. I hope you can get something after reading this article.

Use! Convert variables to Boolean types

Sometimes we need to check whether some variables exist or if they have valid values so that their values are treated as true. For such a check, you can use the | | (double negative operator), which automatically converts any type of data to a Boolean value. Only these variables return false:0,null, "", undefined or NaN, and everything else returns true. Let's take a look at this simple example:

Function Account (cash) {this.cash = cash; this.hasMoney =!! cash;} var account = new Account (100.50); console.log (account.cash); / / 100.50 console.log (account.hasMoney); / / true var emptyAccount = new Account (0); console.log (emptyAccount.cash); / / 0 console.log (emptyAccount.hasMoney); / / false

In this example, if the value of account.cash is greater than zero, the value of account.hasMoney is true.

This is the end of this article on "how to use JavaScript! convert variables to Boolean types". I hope the above content can be helpful to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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