javascript - When you use a string variable to set a properties name why would it ever use the name of the variable itself instead? -

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• using variable key in javascript object literal 6 answers

we using new ecmascript stuff don't know if that's what's going on. do:

var key = "foo"; var obj = { key: "abc" }; 

and created , obj.key property instead of obj.foo property.

that's property name, not expression can variable.

in es6, can make expression:

var obj = { [key]: "abc" };