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How to generate random color with JavaScript
Today we gonna learn how to generate a random color using JavaScript with a few lines :
first we need to know how to get a random number
let randomNumber = Math.random();
//return random number between 0 and 1 (0.46578483)
but we don’t want this result, we need random number integer between 0 and 15
To have it we have use you Math.floor()
let randomNumber = Math.floor(Math.random()*15);
//return random integer between 0 and 15
Well this is the length of an array that contains all alphanumeric of HEX code, and we want to select random index 6 times and join all in one string.
( In this example we will use the HEX code, 0 to 9 and a to f
Ex: #E06910 , #02198C, #BADA55)
const hexArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 'A', 'B', 'C', 'D', 'E', 'F'];
we need to loop 6 times and concatenate the result every time to the code string
let code = "";
for(let i=0; i<6; i++){
code += hexArray[Math.floor(Math.random()*15)];
}
//don' forget the code start with "#"
code = `#${code}`;
now we need to write our code in function to use it perfectly
function generateColor(){
const hexArray = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 'A', 'B', 'C', 'D', 'E', 'F'];
let code = "";
for(let i=0; i<6; i++){
code += hexArray[Math.floor(Math.random()*15)];
}
return `#${code}`
}
In this example I use it in the body background:
document.body.style.backgroundColor = generateColor();
live demo :
I hope you find that useful, if you want to practice more you can create your own function to generate random RGB or HSL color .
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