javascript - JavaScript中是否有常量？(Are there constants in JavaScript?)

Question

Is there a way to use constants in JavaScript?(有没有办法在JavaScript中使用常量？)

If not, what's the common practice for specifying variables that are used as constants?(如果没有，指定用作常量的变量的常见做法是什么？)

  ask by fuentesjr translate from so

Answer 1

Since ES2015 , JavaScript has a notion of const :(从ES2015开始 ，JavaScript有一个const的概念：)

const MY_CONSTANT = "some-value";

This will work in pretty much all browsers except IE 8, 9 and 10 .(除了IE 8,9和10之外，这几乎适用于所有浏览器 。)

Some may also need strict mode enabled.(有些可能还需要启用严格模式 。)

You can use var with conventions like ALL_CAPS to show that certain values should not be modified if you need to support older browsers or are working with legacy code:(您可以将var与ALL_CAPS等约定一起使用，以显示如果您需要支持旧版浏览器或使用旧代码，则不应修改某些值：)

var MY_CONSTANT = "some-value";