forEach() `index` and `array` Parameters2:04 with Joel Kraft
Let's take a look at the forEach() `index` and `array` parameters.
Let me show you just one more thing about forEach before we move on. 0:00 Let's go the MDN documentation page for the forEach method. 0:04 You can see here that the callback in forEach actually accepts some other 0:09 parameters besides the array element we've been using. 0:13 The second parameter will hold the index of the current element. 0:17 So if the current value is the first element, for 0:21 example, the index value will be zero. 0:24 If it's the second element the index will be one, and so on. 0:27 If your code relies on the position of the elements in an array, 0:31 this can be helpful to know. 0:35 The third parameter will hold the whole array itself. 0:37 Neither of these parameters are useful for most applications, but I just wanted to 0:41 make sure you knew about them in case you see examples where they're used. 0:46 I'll just demonstrate the index property quickly. 0:50 Let's say we want to print all the names in this array here, and 0:54 we want to number them as well. 0:59 I'll just add a second parameter, the index, to this callback. 1:03 I'll replace this function body with a call to console.log, 1:14 passing in a template literal. 1:18 Since arrays are zero-based I'm adding 1 to the index, and 1:21 putting a parenthesis, and then the name. 1:26 I'll delete this console.log below the loop as well. 1:29 Now when I run this code, You 1:34 can see the index number has been accessed to provide these numbers. 1:40 One more thing, the index and 1:45 array parameters are available on all of the array methods we cover in this course. 1:47 If you ever have questions about what parameters methods accept, 1:52 I recommend checking out MDN for details. 1:56 I've created some additional practice for you after this video. 1:59
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