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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops The Refactor Challenge

Posted by amin mbarki
amin mbarki
2,110 Points

what's wrong with this code

var html = '';
var red;
var green;
var blue;
var rgbColor;
function randomColor() {
  return math.floor(math.random() * 256 );
}


for (i = 0 ; i < 10 ; i += 1) { 
red = randomColor();
green = randomColor();
blue = randomColor();
rgbColor = 'rgb(' + red + ',' + green + ',' + blue + ')';
html += '<div style="background-color:' + rgbColor + '"></div>';
  document.write(html);
}

my first problem is the function won't work and i didn't get the error in the console second the 'document.write' when i ran it inside the loop the loop ran more than 10 time so it gave me more than 10 circles but outside the loop it works could you guys explain to me why . thanks for helping a lot

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The misspelling of "Math" (as "math" with lower-case "m") is the reason the function isn't working.

And you see more elements than you were expecting because the concatenation assignment operator ("+=") causes the "html" variable to be added to instead of replaced. So each time through the loop, all the previous elements are reprinted along with one new one. To fix it, just change the operator to a normal assignment ("=").