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JavaScript JavaScript and the DOM (Retiring) Getting a Handle on the DOM Select All Elements of a Particular Type

nick schubert
nick schubert
3,535 Points
Posted by nick schubert
nick schubert
3,535 Points

Could someone explain this for loop?

I don't fully understand this for loop, if someone could give me some clarification, that would be great!

I think it works this way: 

for (let i = 0; // You create the variable i in the for loop.
i < myList.length; // if the variable i is less than myList.length
i += 1) // add 1 to i

Is this correct? if so, my issue is that I don't think I would have figured this loop out myself.

Thank you!

3 Answers

Lola Jahn
Lola Jahn
18,718 Points
Lola Jahn
Lola Jahn
18,718 Points

Hey there Nick! You got it almost right.

for (let i = 0; // You create the variable i in the for loop and set it equal to 0
i < myList.length; // the variable i is less than the length of myList (as long as i is less than the length of myList the loop will run) 
i += 1) // add 1 to i every time it loops around

Hope it helped clarifying it a bit.

furkan
furkan
11,733 Points
furkan
furkan
11,733 Points 
for (let i = 0; i < myList.length; i += 1);

/* The for loop is one of the loops you can use in javascript to run a line or multiple codes for a repeated amount of duration. 

In this case, you have created a variable called i and stored the value 0 to it. You then said in your code: run the following loop for as long as the value of i (which is 0) is less than the length value of myList (which I'm guessing it is an array containing multiple values). 

The array index values are where the length property comes from, so however many items you got in your array, that will be the length. So the loop will keep repeating itself and will add a 1 to the value of the variable i each time until the value of i is greater than the length value of myList array.

I hope that has made sense. If not, please refer to Mozilla developer network on Google.
All the best. */
Muhammad Khan
PLUS
Muhammad Khan
Courses Plus Student 8,772 Points
Muhammad Khan
Muhammad Khan
Courses Plus Student 8,772 Points 
for(let i = 0; i < myList.length; i += 1) {
  myList[i].style.color = `red`;
}
/* This is a for loop which is executed as long as a condition is true. the variable i is initialized to 0 as our first position of li is at 0 position because in case of array or collection the position always starts with 0.  i += 1 means in every iteration 1 is added to i to get the next element till the last element (i < myList.length) */ ```