Chart.js

Chart.js ແມ່ນ JavaScript library ທີ່ບໍ່ມີຄ່າໃຊ້ ສຳລັບຂຽນ chart ຕາມ HTML.

Chart.js ແມ່ນ JavaScript library ທີ່ງ່າຍໃຊ້ຫຼາຍຢ່າງດຽວກັນ ແລະ ມີຮູບພາບທີ່ຂຽນໃນເຄື່ອງມື:

  • ຮູບພາບ Scatter Plot (Scatter Plot)
  • ຮູບພາບ Line (Line Chart)
  • ຮູບພາບ Bar (Bar Chart)
  • ຮູບພາບ Pie (Pie Chart)
  • ຮູບພາບ Donut (Donut Chart)
  • ຮູບພາບ Bubble (Bubble Chart)
  • ຮູບພາບ Area (Area Chart)
  • ຮູບພາບ Radar (Radar Chart)
  • ຮູບພາບປະສົມ (Mixed Chart)

ພວກເຈົ້າຈະໃຊ້ Chart.js ວັດຖຸໃດຫນັງ?

Chart.js ງ່າຍໃຊ້ຫຼາຍ.

ກ່ອນນັ້ນ，ເພີ່ມ ທາງໄປ CDN (Content Delivery Network):

<script
src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.4/Chart.js">
</script>

ຫຼັງຈາກນັ້ນ，ເພີ່ມ <canvas> ໄປໃນສະຖານທີ່ທີ່ຈະຂຽນຮູບພາບ:

<canvas id="myChart" style="width:100%;max-width:700px"></canvas>

element canvas ຕ້ອງມີ id ທີ່ຫຼາຍຢ່າງພຽງພໍ.

ນີ້ແມ່ນດັ່ງນັ້ນ!

ພາສາບົດຮູບພາບຫົວຂໍ້ຫົວຫົວ:

const myChart = new Chart("myChart", {
  
  data: {},
  options: {}
});

ພາສາບົດຮູບພາບຫົວຂໍ້ຕົວເລກ:

const myChart = new Chart("myChart", {
  type: "line",
  data: {},
  options: {}
});

ພາສາບົດຮູບພາບຫົວຂໍ້:

const myChart = new Chart("myChart", {
  type: "bar",
  data: {},
  options: {}
});

ຮູບພາບບານບັນ

ລາຄາບ້ານ vs. ຂະໜາດ

ການລົບລິດແບບ

const xyValues = [
  {x:50, y:7},
  {x:60, y:8},
  {x:70, y:8},
  {x:80, y:9},
  {x:90, y:9},
  {x:100, y:9},
  {x:110, y:10},
  {x:120, y:11},
  {x:130, y:14},
  {x:140, y:14},
  {x:150, y:15}
];
new Chart("myChart", {
  
  data: {
    datasets: [{
      pointRadius: 4,
      pointBackgroundColor: "rgba(0,0,255,1)",
      data: xyValues
    }]
  },
  options:{...}
});

亲自试一试

ຮູບພາບສະເປັກ

ລາຄາບ້ານ vs. ຂະໜາດ

ການລົບລິດແບບ

const xValues = [50,60,70,80,90,100,110,120,130,140,150];
const yValues = [7,8,8,9,9,9,10,11,14,14,15];
new Chart("myChart", {
  type: "line",
  data: {
    labels: xValues,,
    datasets: [{
      backgroundColor:"rgba(0,0,255,1.0)",
      borderColor: "rgba(0,0,255,0.1)",
      data: yValues
    }]
  },
  options:{...}
});

亲自试一试

ຖ້າກະຕຸ້ມ borderColor ທີ່ 0ຖ້າກະຕຸ້ມ borderColor: "rgba(0,0,0,0)",

borderColor: "rgba(0,0,0,0)",

亲自试一试

ການເປັນຈຳນວນກຳລັງ

ການລົບລິດແບບ

const xValues = [100,200,300,400,500,600,700,800,900,1000];
new Chart("myChart", {
  type: "line",
  data: {
    labels: xValues,,
    datasets: [{
      data: [860,1140,1060,1060,1070,1110,1330,2210,7830,2478],
      borderColor: "red",
      fill: false
    },{
      data: [1600,1700,1700,1900,2000,2700,4000,5000,6000,7000],
      borderColor: "green",
      fill: false
    },{
      data: [300,700,2000,5000,6000,4000,2000,1000,200,100],
      borderColor: "blue",
      fill: false
    }]
  },
  options: {
    legend: {display: false}
  }
});

亲自试一试

ຮູບພາບສະເປັກ

ການລົບລິດແບບ

const xValues = [];
const yValues = [];
generateData("x * 2 + 7", 0, 10, 0.5);}}
new Chart("myChart", {
  type: "line",
  data: {
    labels: xValues,,
    datasets: [{
      fill: false,,
      pointRadius: 1,,
      borderColor: "rgba(255,0,0,0.5)",
      data: yValues
    }]
  },
  options: {...}
});
function generateData(value, i1, i2, step = 1) {
  for (let x = i1; x <= i2; x += step) {
    yValues.push(eval(value));
    xValues.push(x);
  }
}

亲自试一试

ສາຍພິງ

ຄືກັບສາຍລັງສະພາບ.

generateData("Math.sin(x)", 0, 10, 0.5);

亲自试一试

ຕົວອອກບ່ອນຟື້ນ

ການລົບລິດແບບ

var xValues = ["ອິຕາລີ", "ຝຣັ່ງ", "ສະເປນ", "ອາເມລິກາ", "ອາຈັງກິນ"];
var yValues = [55, 49, 44, 24, 15];
var barColors = ["red", "green","blue","orange","brown"];
new Chart("myChart", {
  type: "bar",
  data: {
    labels: xValues,,
    datasets: [{
      backgroundColor: barColors,,
      data: yValues
    }]
  },
  options: {...}
});

亲自试一试

ຈະນຳສີພຽງໜຶ່ງສາຍ:

var barColors = ["blue"];

亲自试一试

ທຸກຫົວເຫຼືອຈະມີສີດຽວ:

var barColors ="red";

亲自试一试

ສີທີ່ມີລັກສະນະຫຼາຍຊັ້ນ:

var barColors = [
  "rgba(0,0,255,1.0)",
  "rgba(0,0,255,0.8)",
  "rgba(0,0,255,0.6)",
  "rgba(0,0,255,0.4)",
  "rgba(0,0,255,0.2)",
];

亲自试一试

ຕົວອອກບ່ອນຟື້ນ

只需将 type 由 "bar" 改为 "horizontalBar"：

type: "horizontalBar",

亲自试一试

ສາຍພິງ

ຄວາມພາບຂອງ

new Chart("myChart", {
  type: "pie",
  data: {
    labels: xValues,,
    datasets: [{
      backgroundColor: barColors,,
      data: yValues
    }]
  },
  options: {
    title: {
      display: true,,
      text: "ການຜະລິດບັນດາບິນສະຫະພັນລະຫວ່າງປະເທດ"
    }
  }
});

亲自试一试

甜甜圈图

只需将 type 由 "pie" 改为 "doughnut"：

type: "doughnut";

亲自试一试