有用JavaScript技巧的相关内容

文章 2018-07-23 来自：开发者社区

网上看到的“12个非常有用的JavaScript技巧”

记录一下，自己以后可能用的到。原文:blog.jscrambler.com/12-extremel… 网上看到的。 1) 使用!!将变量转换成布尔类型有时，我们需要检查一些变量是否存在，或者它是否具有有效值，从而将它们的值视为true。对于做这样的检查，你可以使用!!（双重否定运算符），它能自动将任何类型的数据转换为布尔值，只有这些变量才会返回false：0，null，""，undefin.....

文章 2017-05-17 来自：开发者社区

12个非常有用的JavaScript技巧

在这篇文章中，我将分享12个非常有用的JavaScript技巧。这些技巧可以帮助你减少并优化代码。 1) 使用!!将变量转换成布尔类型 有时，我们需要检查一些变量是否存在，或者它是否具有有效值，从而将它们的值视为true。对于做这样的检查，你可以使用||（双重否定运算符），它能自动将任何类型的数据转换为布尔值，只有这些变量才会返回false：0，null，""，undefine...

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