Darken Color - JS

by tylerbrownhenry

HTML

<span style="color:#333"></span>

JavaScript

function convertNum(color,change){

   if(color.indexOf('rgb') !== -1){
    var tempColor = color.substring((color.indexOf('(')+1),color.indexOf(')')).split(',');
    color = '';
    for(i=0;i !== 3; i ++){
       tempColor[i] = (parseInt(tempColor[i])).toString(16);
       color += ''+tempColor[i];
    };
   };                    
    color = color.split("");
    var len = color.length,
    darkenColor = new Array();

    
    if(len == 3){
    //hex is 3 digits
        for(i=0; i !== 2; i++){
        color[i+3] = color[i]+''+color[i];
        color[i] = color[i]+''+color[i];
        };
    } else if(len !== 6){
    return "Need a value RGB or HEX Value Please";
    };
    
    for(i=5; color.length > 1;i--){
        num = (parseInt(color.shift(),16)*16)+(parseInt(color.shift(),16));
        darkenColor.push((num - change).toString(16));
    };
    
    return darkenColor.join('');
    
};
color = $('span').css('color');
console.log(convertNum(color,1));