Examples Using forEach()5:08 with Joel Kraft
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
You need to sign up for Treehouse in order to download course files.Sign up