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Alaric Wimer
7,940 PointsWhy is the html variable even used at all?
I produced the same results as Dave with the following code:
for (var i = 1; i <= 10; i += 1) { document.write("<div>" + i + "</div>"); }
I'm curious as to the logic/reasoning behind using the html variable as Dave does in the video. Any help will be greatly appreciated!
2 Answers
Jennifer Nordell
Treehouse TeacherI believe what you're referring to is a case where you start with a variable html and then are constantly building up the string and then using the document.write to write the whole thing at once. This means that only one write will happen to the document.
In your code, that write happens ten times. This might not be much of a performance hit now, but could potentially be a significant performance hit if you needed to have say 1000 divs (for some odd reason). Imagine that you're retrieving entries from a database and each result is a list item in a list. Then you loop over that list and write the item as a list item. That would be mean that you are reaching out and touching the DOM 1000 times instead of just once (assuming there were 1000 results to your query).
Hope this makes sense!
Jonathan Grieve
Treehouse Moderator 91,252 PointsI'd have to see the video and the project for wider context but maybe it's a case of just showing us what HTML elements can be looped over when generating HTML code in a document. The HTML element only occurs once in a document so you don't need to loop that, so you'd only need to store it once in a document.
But I'm merely guessing about what it is your code needs to do. :-)
Alaric Wimer
7,940 PointsAlaric Wimer
7,940 PointsThank you Jennifer! That helps a lot.