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

Posted by Freddie Tantoco
Freddie Tantoco
13,117 Points

How come listHtml only returns the initial <ol> tag once if its in the for loop?

In the function printList();

The variable listHtml is first given the <ol> tag, then in the for loop within that function...

    for ( var i = 0; i < list.length; i++) {
        listHtml += "<li>" + list[i] + "</li>";
    }

So for each time this loop runs list.Html gets added an additional list item. I would think it would return a value like this.

<ol><li>....</li>
<ol><li>....</li>
<ol><li>....</li>
</ol>

Can anyone explain this to me? Please?

1 Answer

Don Hamilton III
Don Hamilton III
31,828 Points
Don Hamilton III
Don Hamilton III
31,828 Points

Hey Freddie,

Your confusion is understandable.

The reason your output code isn't including a new ordered list tag to every list item is because you are adding content to your listHtml variable every time your loop iterates. Your += operator tells javaScript to add whatever code follows to the end of what is already stored in your variable.

So your variable being included in the for loop only references the variable in order to build on to it instead of repeating the code again.

Hope this helps!

Freddie Tantoco
Freddie Tantoco
13,117 Points

Thanks for the explanation Don!

I think I get it now.