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Now that you know how the forEach method works, get some more practice with it.
Let's get some practice
with the forEach method.
0:00
I've cleared out the examples
we wrote in the last video.
0:03
Now let's use the forEach method to create
a new array of the capitalized version of
0:06
these fruits.
0:11
First, I'll create a new array,
capitalizedFruits.
0:12
Now, I'll iterate over
the fruits array with forEach.
0:23
Inside the call back, fruit will
be a string from the fruits array.
0:35
We can capitalize that
string with toUpperCase.
0:40
I'll store the capitalized version of the
string in a variable, capitalizedFruit.
0:43
Now I'll push the capitalized string
into the capitalizedFruits array.
0:59
Let's log this capitalizedFruits array out
so we can see if the program works or not.
1:09
When I run the program,
you can see it works.
1:24
Cool, I wanna give you a challenge.
1:27
I'll erase this console window and
1:30
this code And paste in an array of prices.
1:34
If you want you can copy this
snippet from the teacher's notes and
1:41
paste it into your workspace or
editor, deleting everything else.
1:44
Using forEach, see if you can calculate
a total cost by adding this list of
1:48
prices up and
logging the result to the console.
1:53
I've added a comment here
next to the array, so
1:56
you can see the result your
program should display.
1:59
Pause the video and give it a try.
2:02
Now I'll show you how I
solved this challenge.
2:06
I knew I'd have to keep
track of a total price, so
2:10
I first created a variable
called total and set it to 0.
2:13
Then I wanted to iterate over the prices
array using forEach to get each price.
2:20
I wanted to add each price to the total
and store that value back to total.
2:35
Once all the prices had been added
together, I logged them to the console.
2:44
Running the iteration file.
2:53
You can see it works.
2:58
Lets try one more.
3:01
I'll clear the console and this file.
3:02
And then I'll paste in an array of names.
3:08
Again this is in the snippet section of
the teacher's notes if you'd like to copy
3:14
and paste them.
3:17
See if you can create a new array with
only the names starting with a letter s.
3:19
Here's a hint,
3:23
you'll need to find some way of checking
the first character of each name.
3:24
Check the teacher's notes for
a link to MDN's page on strings,
3:30
if you want to do a little research for
this one.
3:33
Go ahead and pause the video and
see if you can do it.
3:36
Here's how I solved this.
3:40
I first created a variable named sNames
and set it equal to an empty array.
3:43
Then I used forEach to
iterate over the names array.
3:51
I had to check the first letter of each
name to know whether I wanted to add it to
4:04
my sNames array.
4:09
You could do this a couple ways,
I used the charAt string method.
4:11
Passing in 0.
4:20
Because that's the first
position of a string.
4:22
I checked if this was
equal to a capital S.
4:27
If it was, I wanted to add
the name to my sNames array.
4:38
Finally I logged the sNames
array to the console, so
4:47
I could see if my program succeeded.
4:51
I ran the file.
4:59
And it works.
5:05
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