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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops The Refactor Challenge, Part 2

Gavin Broekema
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Gavin Broekema
Full Stack JavaScript Techdegree Student 22,443 Points
Posted by Gavin Broekema
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Gavin Broekema
Full Stack JavaScript Techdegree Student 22,443 Points

Adding an alpha value.

var html = '';
var rgbaColor;

function randomRGB () { 
    return Math.floor(Math.random() * 256 );
}

function randomA () {
    return Math.random();
}

function randomColor () {
    var color = 'rgba(';
    color += randomRGB() + ',';
    color += randomRGB() + ',';
    color += randomRGB() + ',';
    color += randomA() + ')';
    return color;
}

function print(message) {
    document.write(message);
}

for ( var i = 0; i < 50; i++) {
    rgbaColor = randomColor();
    html += '<div style="background-color:' + rgbaColor + '"></div>';
}

print(html);

I decided to experiment within my limits by adding an alpha value. Just curious if this was executed correctly.

Is the function randomA() necessary or no?

Gavin Broekema
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.a{fill-rule:evenodd;}techdegree
Gavin Broekema
Full Stack JavaScript Techdegree Student 22,443 Points
Gavin Broekema
.a{fill-rule:evenodd;}techdegree
Gavin Broekema
Full Stack JavaScript Techdegree Student 22,443 Points

I'm also curious on how I could go about adding a random background color to the body of my html (to make the alpha value more noticeable). Perhaps document.getElementById() would do the trick? But then how do I change the styles?

1 Answer

Mike Ulvila
Mike Ulvila
16,268 Points
Mike Ulvila
Mike Ulvila
16,268 Points

You can set the background color of the body like this.

document.body.style.backgroundColor = "color";