从绿色到红色取决于百分比 [英] from green to red color depend on percentage

问题描述

我有一个民意调查系统，我希望这个民意调查的答案有色。
例如：如果它是10％它将是红色，如果40％它将是黄色而如果80％它将是绿色，所以我希望我的javascript代码使用rgb颜色根据颜色制作颜色给定百分比。

I have a poll system and I want answers for this poll to be colored. For example: If it's 10% it would be red, if 40% it would be yellow and if 80% it would be green, so I want my javascript code to use the rgb colors to make a color according to the given percentage.

function hexFromRGB(r, g, b) {
    var hex = [
        r.toString( 16 ),
        g.toString( 16 ),
        b.toString( 16 )
    ];
    $.each( hex, function( nr, val ) {
        if ( val.length === 1 ) {
            hex[ nr ] = "0" + val;
        }
    });
    return hex.join( "" ).toUpperCase();
}  

现在我想要百分之十六。

Now I want hex from percent.

推荐答案

这可能比您需要的多，但这可以让您设置任意颜色图：

This may be more than you need, but this lets you set up any arbitrary color map:

var percentColors = [
    { pct: 0.0, color: { r: 0xff, g: 0x00, b: 0 } },
    { pct: 0.5, color: { r: 0xff, g: 0xff, b: 0 } },
    { pct: 1.0, color: { r: 0x00, g: 0xff, b: 0 } } ];

var getColorForPercentage = function(pct) {
    for (var i = 1; i < percentColors.length - 1; i++) {
        if (pct < percentColors[i].pct) {
            break;
        }
    }
    var lower = percentColors[i - 1];
    var upper = percentColors[i];
    var range = upper.pct - lower.pct;
    var rangePct = (pct - lower.pct) / range;
    var pctLower = 1 - rangePct;
    var pctUpper = rangePct;
    var color = {
        r: Math.floor(lower.color.r * pctLower + upper.color.r * pctUpper),
        g: Math.floor(lower.color.g * pctLower + upper.color.g * pctUpper),
        b: Math.floor(lower.color.b * pctLower + upper.color.b * pctUpper)
    };
    return 'rgb(' + [color.r, color.g, color.b].join(',') + ')';
    // or output as hex if preferred
}  

这篇关于从绿色到红色取决于百分比的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！