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Chun Wang
1,740 Pointshtml += `<div>${i}</div> logic behind +=?
I was able to complete the for loop without problem, however I'm quite thick in the head and couldn't grasp the logic behind the "+=" in
html += <div>${i}</div>
I know that "+=" produces ${i} from zero to ten, and a "=" only prints out a number ten, but I just can't wrap my head around it.
It'll be awesome if someone could tell me how this logic translates to easy words
2 Answers
Bramyn Payne
Full Stack JavaScript Techdegree Student 19,560 Pointshtml is initialized as an empty string. Each time through the for loop, the += operator adds the new string element. The += operator is just a shorthand way to write it.
html += <div>${i}</div>;
Would be the same as:
html = html + <div>${i}</div>;
So each time through the for loop, the html variable is updated by concatenating the old html string with a new string.
Hopefully this makes a little more sense!
Sara Masek
Front End Web Development Techdegree Student 11,513 Pointshey Chun, it was kind of confusing to me too but I think what the html variable represents is just an initialized placeholder to hold the div elements; in other words, it's like an empty shell that has to be filled with a value (in this case the divs containing the value of "i").
Also, I think using "html" as a variable might have led to confusion. When I see html I immediately look at it as an object to manipulate the DOM rather than an empty variable, which is what this video set it to.
Hope that helps.
rashid sabag
4,647 Pointsvery helpful thanks
Chun Wang
1,740 PointsChun Wang
1,740 PointsI think the part where I don't understand is that: which part of the code allows the "html" before addition to be logged, and not disappear after the addition is complete, like the result with "html = html....".
hope this makes sense.