Difference in browser with Javascript

Question

I'm learning Javascript ECMA6, but I have a problem, I trying a example from my book and results in Chrome and Safari not equal, my question is my question is whether this will affect developments in the future.

var pizzas = ["Margherita", "Mushroom", "Spinach & Rocket", "Pineapple & Sweetcorn"];
delete pizzas[2]

**Safari**
pizzas; //["Margherita", "Mushroom", 3: "Pineapple & Sweetcorn"]

**Chrome**
pizzas; //(4) ["Margherita", "Mushroom", empty, "Pineapple & Sweetcorn"] 0 : "Margherita" 1 : "Mushroom" 3 : "Pineapple & Sweetcorn" 
length : 4

Version Javascript in Chrome : 6.3.292.46

In Chrome I see empty value in 2 position in Chrome and Safari show a '3' in the next value to detele, this is really important to develop in Javascript?

I think that in Firefox is the same result (other result).

Regards

score 2 · Accepted Answer · answered Dec 15 '17 at 19:18

2

delete should not be used on arrays. It does not change array length or re-index the array.

Instead use Array#splice()

pizzas.splice(2,1)

will remove 1 element starting at index=2 and reduce the length of the array by one also

See: Deleting array elements in JavaScript - delete vs splice

answered Dec 15 '17 at 19:18

charlietfl

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Perfect! but What is the real purpose to use delete (in my book the authors use this to Removing Values from Arrays) – Javiera Mena Dec 15 '17 at 19:23
That sounds like a scary book. Or possibly very very old. Or you have taken it out of context and they are deleting properties of objects in arrays – charlietfl Dec 15 '17 at 19:25
The book is Novice to Ninja Javascript, do you have a book most updated? – Javiera Mena Dec 15 '17 at 19:27
Not me. I've never read a programming book in my life to be honest – charlietfl Dec 15 '17 at 19:28
But do you have somewhere where I can find good documentation about Javascript and guide me about it? Thanks bro! – Javiera Mena Dec 15 '17 at 19:29
MDN Docs as per the link I used for `splice()` above – charlietfl Dec 15 '17 at 19:31

Difference in browser with Javascript

1 Answers1