javascript - how to keep value of variable after making it null -


i know sounds silly asking, there way of keeping value of b variable after delete a variable?

var = 'some string or number'; var b = a;  delete a;  b still = 'some string or number';

or other way keep b value?

delete not delete values or variables, deletes properties on object (mdn: https://developer.mozilla.org/en-us/docs/web/javascript/reference/operators/delete).

for instance:

var myobj = { a: 1, b: 2 }; delete myobj.a; // myobj === { b: 2 }

of course can keep reference value in variable: var copy = myobj.a (before delete property). variable hold value (for primitives basic numbers, strings, booleans) or reference (for objects etc.). either way, copy hold value still after original property has been deleted:

var obj = { a: "hello" }; var copy = obj.a; delete obj.a; console.log(copy); // "hello"

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