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yo so uh what's up today I'm going to be
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talking about the sort method in
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JavaScript the sort method is used to
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sort elements of an array in place
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however with the sort method we sort
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elements as strings in lexicographic
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order not alphabetical if I could
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summarize what lexicographic means it
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means alphabet Plus numbers plus symbols
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as strings let me give you an example
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with just alphabetical characters I have
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an array of fruits to sort this array I
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can take the array name fruits use the
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built-in sort method then
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console.log my array of fruits let me
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expand this and here's my array all
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sorted when sorting we treat any
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elements as strings what if my array
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were numbers I'll add the numbers 1
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through 10 in a somewhat random
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order let's change our array to be
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numbers numbers. sort console.log
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numbers here's the result we have one
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then 10 then the rest seem to be in
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order we're not sorting this array
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numerically we're sorting this array
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lexor graphically we're treating each of
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these numbers as strings that's why we
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have one then 10 10 isn't at the end
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where we expect it would be there's a
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couple extra steps we need to do
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involving sorting
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numbers inside of the sort method we
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have to write a custom comparison
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function this is normally a callback but
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you can write a function expression or
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even better yet an arrow function we'll
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write an arrow function in this case let
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me zoom in with an arrow function we
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first need
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parameters we'll have parameters A and B
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we'll examine two contiguous elements 1
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then 10 10 then 2 two then nine N9 and
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three so on and so forth then we need an
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arrow
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then we'll write a minus B our function
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a minus B will return either a0 or
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positive value depending on what values
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we're examining the sort method will
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sort those values into place depending
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on what the value returned is our array
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should be sorted you can see that 10 is
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at the end instead of right after one
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for reverse order you could say B minus
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a now we're starting with 10 and ending
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with
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one you can even sort objects by a given
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property let's go over that
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example we will create an array of
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people const people equals this will be
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an array will include four objects all
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comma
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separated the first will have a name
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property of
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SpongeBob age
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30 and a GPA
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GPA
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3.0 I'm going to zoom out for the next
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object just going to put that on a new
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line let's copy all these properties
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change name to be Patrick age will be
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37 GPA
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1.5 again for the next
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object we will have
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Squidward
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age
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51 GPA
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2.5 then lastly we'll have Sandy name
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Sandy let's make Sandy
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27 GPA of course it's going to be a
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4.0 I would like to sort this array of
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objects by each person's age we'll take
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our array of objects that's stored
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within
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people use the built-in sort
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method use our Arrow
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function a comma B
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Arrow we'll take parameter a that's
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person one do access their age property
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minus parameter B access their age
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property and that's all you got to do
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now let's
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console.log R
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people
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there we are we have Sandy who's the
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youngest then SpongeBob Patrick
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Squidward for reverse order you'll just
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change a to be B and B to be
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a Squidward Patrick SpongeBob Sandy or
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we can sort by a different property
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let's do GPA this
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time a. GPA b. GPA
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we have Patrick with the lowest GPA
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followed by Squidward SpongeBob Sandy
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then reverse order would be b. GPA minus
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a.
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GPA Sandy SpongeBob Squidward Patrick
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let's try sorting by the name property
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and see what happens
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a.name minus b.n
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name we have SpongeBob Patrick's
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Squidward Sandy but that doesn't seem to
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make sense these aren't in alphabetical
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order if you need to sort by a property
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that contains a string within an object
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there's a different
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formula we will take
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a.name do use the built-in
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local compare
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method compare to b.
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name this method will examine two
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strings for lexicographic
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order now these are all arranged
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lexicographically starting with Patrick
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then Sandy SpongeBob Squidward for
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reverse lexicographic order we would
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take b.n name. local compare then
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examine
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a.name I've just now realized that
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there's a lot of SpongeBob characters
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whose first name starts with an S like
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we have three right here Squidward
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SpongeBob Sandy Patrick all right
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everybody so that is the sort method
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it's used to sort elements of an array
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in place it sorts elements as strings in
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lexicographic order not alphabetical and
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well everybody that is the sort method
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in
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JavaScript