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newwebcoder
13,061 PointsConst in DOM
Hello everyone!
I have a little question. So, my code is working properly however I don’t understand one thing. Why is it possible to modify / change content which we store in ‘const’?
Example: const deleteButton = document.createElement('button'); deleteButton.textContent = 'Delete';
Was it mentioned somewhere in the DOM tutorials? I understand that we can also use ‘let / var’ instead of ‘const’ but shouldn’t only ‘let / var’ work in this case?
1 Answer
Zimri Leijen
11,835 PointsWell, that's a little thing about javacript.
When you make a const, the constant itself is constant, but the properties of the constant aren't.
So while javascript will throw an error if you change deleteButton, since that's a const, it will be completely fine with you changing the property deleteButton.textContent
terry okey
3,187 PointsOh wow thanks. I've been wondering that for weeks.
Gary A
3,753 PointsGary A
3,753 PointsEssentially, the constant means a memory address. Think of it like your phone number. Your phone number is an address of your phone's location... when you call that phone... the person answering it can change... but the phone number itself is constant.
Street addresses work the same way. If you list your address somewhere you can get mail sent to that location... but the properties of that house can change. You can even make that address NULL by demolishing the house.... but the address still exists. It's constant.
When you use const, you can't change the address... so someone can't pull a fast one and point your mail somewhere else... they can't suddenly say that 123 Main Street, 90210 is in a different city and steal your amazon packages.
Using LET means you have a forwarding address or a PO Box that can be forwarded wherever you want it.