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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Using For Loops with Arrays

Volodymyr Boretskyi
Volodymyr Boretskyi
9,094 Points
Posted by Volodymyr Boretskyi
Volodymyr Boretskyi
9,094 Points

clarify + list[i] +

can someone clarify please this + list[i] + when we build listHTML += '<li>' + list[i] + '</li>'; ?

Thanks

2 Answers

liktid
liktid
6,387 Points
liktid
liktid
6,387 Points

This means that "list[i]" is an array within a loop. The + is a concatenation operator, which "connects" - in this case - the html <li>-tags with the array. While "i" is the variable with the value of the current loop (e.g. 1 or 2 or 3 depending on the condition) is "list" referring to the array.

Example:

var arrayExample = [arrayItem1, arrayItem2, arrayItem3];

list[i] is now looping through the array with i changing its value in every round.

list[0] = arrayItem1;
list[1] = arrayItem2;
list[2] = arrayItem3;

With the concatenation operator it would look like:

<li>arrayItem1</li>
<li>arrayItem2</li>
<li>arrayItem3</li>

I hope this helps.