Accordingly, we can push it in our temporary array and return. Because, since the beginning of JavaScript typeof null is equals to object. You can read more about it here. Here we are checking if a value is blank or not using val.
In this code, we will merge our functionality of removing null, undefined and empty values. This can be used to remove all kinds of undesired values. Tweet this to help others. Vega Supravat Paul Supravat Paul 17 4 4 bronze badges. NET which the original question did not reference at all.
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It actually modifies the array in question and subsequently all references get affected. See the test on my jsFiddle: jsfiddle. Read the docs first: developer.
We could prevent the resulting array from being returned by using the comma operator : A. This would leave a return value of 0 just as A. Browser implementation will affect this although I see no reason why splice would be faster than setting length. I have also found that just A. Show 6 more comments. The answers that have no less that upvotes by now are misleading and incorrect.
The question is: "How do you empty your existing array? Let's say your mother asks you to empty the trash can. You don't bring in a new one as if you've done what you've been asked for. Instead, you empty the trash can. You were asked to empty the existing one, completely, in one turn, not to pick up the trash until the can gets empty, as in: while A.
MultiplyByZer0 4, 3 3 gold badges 29 29 silver badges 46 46 bronze badges. Bekim Bacaj Bekim Bacaj 5, 2 2 gold badges 19 19 silver badges 25 25 bronze badges. The only problem with your suggested solution is that the trash still exists, it is just that you changed the notice board saying that there is no trash. A reference to the old array should still exist. Can you be sure the garbage collector when setting. I think it does though, but to me that is magic.
I never stated that this solution is wrong. The problem is that this entire thread is completely unncessary. Over votes shows that trying to figure out what the best way is should make it a valid enough case for the EMCA crack head developers to add such a method. Nobody should have to go through figuring it out. There are three - four different ways to do it. In some benchmarks, the length solutions is much slower than others.
Furthermore, the idea of setting. Because to accomplish what it should, all references must be removed. Therefore, I'd rather clear it myself. A clear method can be prototyped but that is just ugly. My point is that this implementation should already be present so that over 10 developers didn't have to spend hours reading just this thread, not considering all others who spent more time benchmarking.
I loved the metaphors with the real world in this answer. Show 8 more comments. Adding the percentage changes arent much use without also noting your platform. On my machine pop is only very mildly quicker in Chrome 34 but actually slower than [] in latest Firefox.
Testing in Firefox There is definitely something fishy in this test result under Chrome. How in hell can the popping loop be that much faster then the other 3 solutions? It's the slowest method. The benchmark test is flawed.
Please delete this answer as it is wrong, and links to a meaningless flawed test as fake evidence. Show 2 more comments. You can add this to your JavaScript file to allow your arrays to be "cleared": Array.
It is "frowned upon" to modify javascript primitive functions like Array and String. You could possibly be overloading an already existing function and trash the object class. There might be an obscure javascript engine that already has clear and expects it to behave a different way. Tread carefully is all I say. How about the problem where doing a foreach over the members of an array will suddenly start including a clear key?
As a reference: Why is extending native objects a bad practice? Add a comment. Connect and share knowledge within a single location that is structured and easy to search.
I have to copy the content of all these array value to the postal address textarea. How to remove this extra commas? You can use filter to filter out the null values:. Use filter method to remove all falsy values:. Underscore is a nice utility library for functional programming and list manipulation:. One could also use Array. If you would like to eliminate all the undefined, null, NaN, "", 0, a simple way to do it is to use a combination of filter call back function and boolean function.
When you pass a value to the boolean function, if the value is omitted or is 0, -0, null, false, NaN, undefined, or the empty string "" , the object has an initial value of false. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Remove null values from javascript array Ask Question.
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