Warning. This post about arrays has no filter()!
I love to manipulate arrays into doing my bidding, break 'em down, twist them to my will. It gives me a dirty thrill to take an array back to my homepage and push() in to it, Pop() a couple datum off its ass, then bring my neighbor Cat over and concat() into inserting herself into the situation.
Then after a <br>
...when the array starts to relax, thinks I've finished, I unshift("gears"), shove my data in its face, and when the array has taken all the data I have to give, I grab my [] cutter and splice(n, 2, "it my initials", "ever so gently"). When the array winces, I offer it something to numb the pain then I join() it and we both lay on the floor, panting, strung out.
...If that passage didn't get arrays out of you, then maybe you need some hard facts about dealing with arrays to get your blood pumping.
Push:
Pushing is like doin' it doggy style with an array. i.e. Push shoves a new item (or items) into the back of an array.
syntax: array.push(newItem1 [, newItem2, etc]);
* anything inside of [within my examples indicates optional arguments... you shouldn't actually put square brackets in a functions arguments ]
NOTE, when you push to an array, you are changing the original array, so once you push to an array, you will only be able to reference the new, manipulated array.
syntax: array.push(newItem1 [, newItem2, etc]);
* anything inside of [within my examples indicates optional arguments... you shouldn't actually put square brackets in a functions arguments ]
NOTE, when you push to an array, you are changing the original array, so once you push to an array, you will only be able to reference the new, manipulated array.
Also note, pushing an entire array (or arrays) into an existing array will not insert the contents of the inserted array, but will rather, create a multidimensional array… and if you are viewing multidimensional arrays in Google dev Tools, the data is truncated, but details of the contents of the internal arrays can be viewed by clicking on the arrow beside them.
Pop:
Popin’ a cap off in someone’s ass works exactly like poppin’ an item off of an array (where the array is the chamber of yo’ “gun” and the data is the “bullet” you just fired) well kinda… pop removes the last item from an array.
syntax: array.pop();
note —like push, you are manipulating the original array. However, unlike push, the parenthesis are left empty because you can only pop off one item from an array at a time.
Popin’ a cap off in someone’s ass works exactly like poppin’ an item off of an array (where the array is the chamber of yo’ “gun” and the data is the “bullet” you just fired) well kinda… pop removes the last item from an array.
syntax: array.pop();
note —like push, you are manipulating the original array. However, unlike push, the parenthesis are left empty because you can only pop off one item from an array at a time.
Unshift:
If you want to shove data into an arrays face, use unshift. Unshift does to the 0th end of an array everything that push does to the array.length end of an array.
syntax: array.unshift(newItem1 [, newItem2, etc]);
note: an array can contain any combination of any type of data (strings, numbers, objects, etc)
syntax: array.unshift(item1 [item2, etc])
If you want to shove data into an arrays face, use unshift. Unshift does to the 0th end of an array everything that push does to the array.length end of an array.
syntax: array.unshift(newItem1 [, newItem2, etc]);
note: an array can contain any combination of any type of data (strings, numbers, objects, etc)
syntax: array.unshift(item1 [item2, etc])
Shift:
Shifting data out of an array is like when you have a line of lovers before you and you don’t like the look of the one in front, so you ask that one to shift to one side and let the next one move to the front… except with an array rather than just shifting aside, you remove the item entirely. i.e. shift is like pop, but the item from the front of the array is remove rather than the item from the back.
syntax: array.shift();
Slice:
Going back to the line of lovers. If there are one or two particularly enticing prospects in the middle of your line and you want to yank them out and deal with them privately before putting them back in line, you’d want to slice them out. Slice is a method that takes 2 arguments, the first of which is the index of the first item you wish to remove and the second argument is the position that follows the last item you want to remove. Slicing from an array removes items, but does not mutate the original array. So if you wish to reference the removed items in the future you should set them equal to a variable. NOTE if you only give one argument, slice will begin from the 0 index and slice items up to (but not including) the index you have given .
Going back to the line of lovers. If there are one or two particularly enticing prospects in the middle of your line and you want to yank them out and deal with them privately before putting them back in line, you’d want to slice them out. Slice is a method that takes 2 arguments, the first of which is the index of the first item you wish to remove and the second argument is the position that follows the last item you want to remove. Slicing from an array removes items, but does not mutate the original array. So if you wish to reference the removed items in the future you should set them equal to a variable. NOTE if you only give one argument, slice will begin from the 0 index and slice items up to (but not including) the index you have given .
syntax: var sliced = array.slice([indexOfItem1,] indexAfterLastItem);
Splice:
If you’ve got some fuglies in your line and you just want them gone and put somewhere else, you can splice them out — and if you wish, you can splice in one or more replacements into the line. The splice method takes at least 2 arguments. The first is the index of the first item you wish to remove and the second argument is the total number of items you want to remove. If you are splicing IN to the array, you can add an additional argument for each item you would like to splice into the array. If you wish TO ADD ONLY (but not remove from the array), your second argument should be 0. Splicing mutates the original array, and you can also set a variable equal to the splice method you are calling to create a separate array containing any items you spliced out. NOTE If you put only one argument, all items after the first given index will be removed.
If you’ve got some fuglies in your line and you just want them gone and put somewhere else, you can splice them out — and if you wish, you can splice in one or more replacements into the line. The splice method takes at least 2 arguments. The first is the index of the first item you wish to remove and the second argument is the total number of items you want to remove. If you are splicing IN to the array, you can add an additional argument for each item you would like to splice into the array. If you wish TO ADD ONLY (but not remove from the array), your second argument should be 0. Splicing mutates the original array, and you can also set a variable equal to the splice method you are calling to create a separate array containing any items you spliced out. NOTE If you put only one argument, all items after the first given index will be removed.
syntax: [var spliced =] array.splice(indexToBeginSplicing, numberOfItemsToSpliceOut [AdditionalitemsToSpliceIn]);
Concat:
Like the story at the beginning of this blog post if you want to get inside two arrays at once, you have to concat. Because when you concat two arrays, the contents of the second array are inserted into the back of the first array.
note concat does not mutate the original array, so if you wish to reference the concatenated array in the future you must set a variable equal to the concatenated array.
syntax: var concatedArray = array1.concat(array2)
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