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 function drawCircle(canvasId, option) { const color_arr = option.color let data_arr = option.data const pi2 = Math.PI * 2; let canvas = document.getElementById(canvasId); let c = canvas.getContext("2d"); let startAgl = 0; let agl; let sum = 0; const cW = canvas.width; const cH = canvas.height; for (let item of data_arr) { sum += item.value * 1.0 } data_arr = data_arr.map((v, i) => { return { name: v.name, value: (v.value) * 1.0 / sum } }) for (let i = 0; i < data_arr.length; i++) { //绘制饼图 let min = (cW > cH ? cH : cW); //获取canvas宽高的最小值 agl = data_arr[i].value * pi2 + startAgl; //终点 c.strokeStyle = color_arr[i]; c.lineWidth = data_arr[i].value * min * 0.3; // 线的粗细 c.beginPath(); c.arc(cW / 2, cH / 2, min * 0.3, startAgl, agl, false); //画圆 c.stroke(); c.closePath(); startAgl = agl; //绘制图例 c.fillStyle = color_arr[i]; c.fillRect(cW * 0.8, 50 + 18 * i, 16, 16); c.fillText(data_arr[i].name, cW * 0.8 + 20, 62 + 18 * i); } } 

 let color = ['#0580F2', '#FAA732', '#E1575D', '#8B73CC', '#8CD123', '#4B53BA', '#429588']; let option = { color: color, data: [ { name: '20', value: '20' }, { name: '30', value: '30' }, { name: '40', value: '40' }, { name: '50', value: '50' }, { name: '60', value: '60' }, ] } drawCircle('myCanvas', option)