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javascriptconstants

Are there constants in JavaScript?

Is there a way to use constants in JavaScript?

If not, what's the common practice for specifying variables that are used as constants?

Solution

  • Since ES2015, JavaScript has a notion of const:

    const MY_CONSTANT = "some-value";

    This will work in pretty much all browsers except IE 8, 9 and 10. Some may also need strict mode enabled.

    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:

    var MY_CONSTANT = "some-value";