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Adding Items to Arrays
3:26Now that we know how to create a Ruby array, let's learn a few ways to add items to it.
Now that we know how to create an array,
let's look at how to add things to it.
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Once we have an array,
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there are a few different ways
of adding items to that array.
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Let's see how that works
now using workspaces.
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So here's another workspace, and I've
created a file called arr_addition.rb.
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If you want to check out what
we did in IRB in the last video,
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it'll be there in array_creation.rb.
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So now let's go ahead and
check out this file.
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Here we have our grocery_list array.
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It contains three items,
"milk", "eggs" and "bread".
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We can see the contents of an array if we
run it using a Ruby program file by typing
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puts, and we can do grocery_list.inspect.
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And that will print out the contents
of the array onto the screen.
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Let's go ahead and run this file
by typing ruby array_addition.rb.
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Now we can see we have our array.
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Let's go ahead and
add something on to this.
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So I've just clicked up onto line two and
if I want to add on to the grocery list,
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I could say grocery_list and then two
less than signs and add another item.
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And that will append the item
onto the end of the array.
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Now if I run this,
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we can see that there is another item
at the end of the array called "carrots".
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Another method of adding
something to the end of an array
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is to use a method called push.
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So we could say grocery_list and
then a dot and then push and
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then open parenthesis
and the word "potatoes".
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This is getting to be
a pretty big grocery list.
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Now if we print this out,
we can see we have "carrots" and
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"potatoes" at the end of our original array.
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But what happens if we wanted to add
something to the beginning of the array?
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In that case,
we could use the method called unshift.
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Which, instead of adding
something to the end of the array,
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we'll add it to the beginning.
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And we'll put "celery" at
the beginning of the grocery list
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because we're eating healthy.
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Now if we run this, we can see that
"celery" is here at the beginning
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as opposed to "carrots" and "potatoes"
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which were at the end.
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If we wanted to we could also use
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the plus equals operator and
add more items onto the array that way.
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Let's go ahead and
get some desserts in here.
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So we'll add "ice cream" and "pie".
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And you'll notice that I'm
adding another array here.
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Let's run that and see what happens.
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and it looks like "ice cream" and
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"pie" were successfully added
to the end of our array.
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Now, we're not limited to just Strings.
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We could also add numbers
if we wanted as well.
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Or actually,
almost any Ruby type can go in there.
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Try adding on to your arrays
now using WorkSpaces.
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