javascript - JS Canvas 运动动画循环-6ren

javascript - JS Canvas 运动动画循环

转载作者：塔克拉玛干更新时间：2023-11-02 21:23:26

我有一个对象渲染到 Canvas 上。我试图让对象在一个循环中沿着设定的路径移动。这是我所拥有的:

// Canvas Element
var canvas = null;

// Canvas Draw
var ctx = null;

// Static Globals
var tileSize = 16,
    mapW = 10,
    mapH = 10;

// Instances of entities
var entities = [
  // A single entity that starts at tile 28, and uses the setPath() function
  {
    id: 0,
    tile: 28,
    xy: tileToCoords(28),
    width: 16,
    height: 24,
    speedX: 0,
    speedY: 0,
    logic: {
      func: 'setPath',
      // These are the parameters that go into the setPath() function
      data: [0, ['down', 'up', 'left', 'right'], tileToCoords(28), 0]
    },
    dir: {up:false, down:false, left:false, right:false}
  }
];

// Array for tile data
var map = [];

window.onload = function(){

  // Populate the map array with a blank map and 4 walls
  testMap();
  
  canvas = document.getElementById('save');
  ctx = canvas.getContext("2d");

  // Add all the entities to the map array and start their behavior
  for(var i = 0; i < entities.length; ++i){

    map[entities[i].tile].render.object = entities[i].id;

    if(entities[i].logic){        
      window[entities[i].logic.func].apply(null, entities[i].logic.data);
    }
  }

  drawGame(map);
  window.requestAnimationFrame(function(){
    mainLoop();
  });
};

function drawGame(map){
  ctx.clearRect(0, 0, canvas.width, canvas.height);

  // We save all the entity data for later so the background colors don't get rendered on top
  var tileObjData = [];

  for(var y = 0; y < mapH; ++y){
    for(var x = 0; x < mapW; ++x){

      var currentPos = ((y*mapW)+x);

      ctx.fillStyle = map[currentPos].render.base;
      ctx.fillRect(x*tileSize, y*tileSize, tileSize, tileSize);

      var thisObj = map[currentPos].render.object;

      if(thisObj !== false){

        thisObj = entities[thisObj];
        var originX = thisObj.xy.x;
        var originY = thisObj.xy.y;
        tileObjData.push(
          {
            id: thisObj.id,
            originX: originX, 
            originY: originY, 
            width: thisObj.width, 
            height: thisObj.height,
          }
        );
      }
    }
  }
  
  // Draw all the entities after the background tiles are drawn
  for(var i = 0; i < tileObjData.length; ++i){
    drawEntity(tileObjData[i].id, tileObjData[i].originX, tileObjData[i].originY, tileObjData[i].width, tileObjData[i].height);
  }
}

// Draws the entity data
function drawEntity(id, posX, posY, sizeX, sizeY){

  var offX = posX + entities[id].speedX;
  var offY = posY + entities[id].speedY;
  
  ctx.fillStyle = '#00F';
  ctx.fillRect(offX, offY + sizeX - sizeY, sizeX, sizeY);

  entities[id].xy.x = offX;
  entities[id].xy.y = offY;
}

// Redraws the canvas with the browser framerate
function mainLoop(){
  drawGame(map);

  for(var i = 0; i < entities.length; ++i){
    animateMove(i, entities[i].dir.up, entities[i].dir.down, entities[i].dir.left, entities[i].dir.right);
  }

  window.requestAnimationFrame(function(){
    mainLoop();
  });
}

// Sets the speed, direction, and collision detection of an entity
function animateMove(id, up, down, left, right){

  var prevTile = entities[id].tile;

  if(up){

    var topLeft = {x: entities[id].xy.x, y: entities[id].xy.y};
    var topRight = {x: entities[id].xy.x + entities[id].width - 1, y: entities[id].xy.y};

    if(!map[coordsToTile(topLeft.x, topLeft.y - 1)].state.passable || !map[coordsToTile(topRight.x, topRight.y - 1)].state.passable){
      entities[id].speedY = 0;
    }
    else{
      entities[id].speedY = -1;
    }
  }
  else if(down){

    var bottomLeft = {x: entities[id].xy.x, y: entities[id].xy.y + entities[id].width - 1};
    var bottomRight = {x: entities[id].xy.x + entities[id].width - 1, y: entities[id].xy.y + entities[id].width - 1};

    if(!map[coordsToTile(bottomLeft.x, bottomLeft.y + 1)].state.passable || !map[coordsToTile(bottomRight.x, bottomRight.y + 1)].state.passable){
      entities[id].speedY = 0;
    }
    else{
      entities[id].speedY = 1;
    }
  }
  else{
    entities[id].speedY = 0;
  }

  if(left){

    var bottomLeft = {x: entities[id].xy.x, y: entities[id].xy.y + entities[id].width - 1};
    var topLeft = {x: entities[id].xy.x, y: entities[id].xy.y};

    if(!map[coordsToTile(bottomLeft.x - 1, bottomLeft.y)].state.passable || !map[coordsToTile(topLeft.x - 1, topLeft.y)].state.passable){
      entities[id].speedX = 0;
    }
    else{
      entities[id].speedX = -1;
    }
  }
  else if(right){

    var bottomRight = {x: entities[id].xy.x + entities[id].width - 1, y: entities[id].xy.y + entities[id].width - 1};
    var topRight = {x: entities[id].xy.x + entities[id].width - 1, y: entities[id].xy.y};

    if(!map[coordsToTile(bottomRight.x + 1, bottomRight.y)].state.passable || !map[coordsToTile(topRight.x + 1, topRight.y)].state.passable){
      entities[id].speedX = 0;
    }
    else{
      entities[id].speedX = 1;
    }
  }
  else{
    entities[id].speedX = 0;
  }

  entities[id].tile = coordsToTile(entities[id].xy.x + (entities[id].width / 2), entities[id].xy.y + (tileSize / 2));
  map[entities[id].tile].render.object = id;

  if(prevTile !== entities[id].tile){
    map[prevTile].render.object = false;
  }
}

//////////////////////////////////////
// THIS IS WHERE I'M HAVING TROUBLE //
//////////////////////////////////////
// A function that can be used by an entity to move along a set path
// id = The id of the entity using this function
// path = An array of strings that determine the direction of movement for a single tile
// originPoint = Coordinates of the previous tile this entity was at. This variable seems to be where problems happen with this logic. It should get reset for every tile length moved, but it only gets reset once currently.
// step = The current index of the path array 
function setPath(id, path, originPoint, step){

  // Determine if the entity has travelled one tile from the origin
  var destX = Math.abs(entities[id].xy.x - originPoint.x);
  var destY = Math.abs(entities[id].xy.y - originPoint.y);

  if(destX >= tileSize || destY >= tileSize){
    // Go to the next step in the path array
    step = step + 1;
    if(step >= path.length){
      step = 0;
    }
    // Reset the origin to the current tile coordinates
    originPoint = entities[id].xy;
  }
  
  // Set the direction based on the current index of the path array
  switch(path[step]) {

    case 'up':
      entities[id].dir.up = true;
      entities[id].dir.down = false;
      entities[id].dir.left = false;
      entities[id].dir.right = false;
      break;

    case 'down':
      entities[id].dir.up = false;
      entities[id].dir.down = true;
      entities[id].dir.left = false;
      entities[id].dir.right = false;
      break;

    case 'left':
      entities[id].dir.up = false;
      entities[id].dir.down = false;
      entities[id].dir.left = true;
      entities[id].dir.right = false;
      break;

    case 'right':
      entities[id].dir.up = false;
      entities[id].dir.down = false;
      entities[id].dir.left = false;
      entities[id].dir.right = true;
      break;
  };

  window.requestAnimationFrame(function(){
    setPath(id, path, originPoint, step);
  });
}

// Take a tile index and return x,y coordinates
function tileToCoords(tile){

  var yIndex = Math.floor(tile / mapW);
  var xIndex = tile - (yIndex * mapW);

  var y = yIndex * tileSize;
  var x = xIndex * tileSize;
  return {x:x, y:y};
}

// Take x,y coordinates and return a tile index
function coordsToTile(x, y){

  var tile = ((Math.floor(y / tileSize)) * mapW) + (Math.floor(x / tileSize));
  return tile;
}

// Generate a map array with a blank map and 4 walls
function testMap(){
  for(var i = 0; i < (mapH * mapW); ++i){

    // Edges

    if (
      // top
      i < mapW || 
      // left
      (i % mapW) == 0 || 
      // right
      ((i + 1) % mapW) == 0 || 
      // bottom
      i > ((mapW * mapH) - mapW)
    ) {

      map.push(
        {
          id: i,
          render: {
            base: '#D35',
            object: false,
            sprite: false
          },
          state: {
            passable: false
          }
        },
      );

    }
    else{

      // Grass

      map.push(
        {
          id: i,
          render: {
            base: '#0C3',
            object: false,
            sprite: false
          },
          state: {
            passable: true
          }
        },
      );

    }
  }
}

<!DOCTYPE html>
<html>
<head>

  <style>

    body{
      background-color: #000;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #FFF;
      font-size: 18px;
      padding: 0;
      margin: 0;
    }

    main{
      width: 100%;
      max-width: 800px;
      margin: 10px auto;
      display: flex;
      align-items: flex-start;
      justify-content: center;
      flex-wrap: wrap;
    }

    .game{
      width: 1000px;
      height: 1000px;
      position: relative;
    }

    canvas{
      image-rendering: -moz-crisp-edges;
      image-rendering: -webkit-crisp-edges;
      image-rendering: pixelated;
      image-rendering: crisp-edges;
    }

    .game canvas{
      position: absolute;
      top: 0;
      left: 0;
      width: 800px;
      height: 800px;
    }

  </style>
  
</head>
<body>
  
  <main>
    <div class="game">
      <canvas id="save" width="200" height="200" style="z-index: 1;"></canvas>
    </div>
  </main>

</body>
</html>

问题出在 setPath() 函数上，更具体地说，我认为它出在 originPoint 变量上。这个想法是 setPath() 将对象每个 path 字符串移动一个瓦片，而 originPoint 应该是最后访问的瓦片的坐标(所以只有当对象坐标距 originPoint 一个瓦片长度时，它才会更新)。现在它只会第一次更新然后停止。希望有人能指出我在这里做错了什么。

最佳答案

你改变路径方向的条件我把它改成每个方向都有条件，比如:

if ((entities[id].dir.left  && entities[id].xy.x <= tileSize) ||    
  (entities[id].dir.right && entities[id].xy.x >= tileSize*8) || 
  (entities[id].dir.up    && entities[id].xy.y <= tileSize) ||
  (entities[id].dir.down  && entities[id].xy.y >= tileSize*8)) {

originPoint 只是您应该做的引用:

originPoint = JSON.parse(JSON.stringify(entities[id].xy));

查看下面的工作代码

// Canvas Element
var canvas = null;

// Canvas Draw
var ctx = null;

// Static Globals
var tileSize = 16,
    mapW = 10,
    mapH = 10;

// Instances of entities
var entities = [
  // A single entity that starts at tile 28, and uses the setPath() function
  {
    id: 0,
    tile: 28,
    xy: tileToCoords(28),
    width: 16,
    height: 24,
    speedX: 0,
    speedY: 0,
    logic: {
      func: 'setPath',
      // These are the parameters that go into the setPath() function
      data: [0, ['down', 'left', 'down', 'left', 'up', 'left', 'left', 'right', 'up', 'right', 'down','right', "up"], tileToCoords(28), 0]
    },
    dir: {up:false, down:false, left:false, right:false}
  }
];

// Array for tile data
var map = [];

window.onload = function(){

  // Populate the map array with a blank map and 4 walls
  testMap();
  
  canvas = document.getElementById('save');
  ctx = canvas.getContext("2d");

  // Add all the entities to the map array and start their behavior
  for(var i = 0; i < entities.length; ++i){

    map[entities[i].tile].render.object = entities[i].id;

    if(entities[i].logic){        
      window[entities[i].logic.func].apply(null, entities[i].logic.data);
    }
  }

  drawGame(map);
  window.requestAnimationFrame(function(){
    mainLoop();
  });
};

function drawGame(map){
  ctx.clearRect(0, 0, canvas.width, canvas.height);

  // We save all the entity data for later so the background colors don't get rendered on top
  var tileObjData = [];

  for(var y = 0; y < mapH; ++y){
    for(var x = 0; x < mapW; ++x){

      var currentPos = ((y*mapW)+x);

      ctx.fillStyle = map[currentPos].render.base;
      ctx.fillRect(x*tileSize, y*tileSize, tileSize, tileSize);

      var thisObj = map[currentPos].render.object;

      if(thisObj !== false){

        thisObj = entities[thisObj];
        var originX = thisObj.xy.x;
        var originY = thisObj.xy.y;
        tileObjData.push(
          {
            id: thisObj.id,
            originX: originX, 
            originY: originY, 
            width: thisObj.width, 
            height: thisObj.height,
          }
        );
      }
    }
  }
  
  // Draw all the entities after the background tiles are drawn
  for(var i = 0; i < tileObjData.length; ++i){
    drawEntity(tileObjData[i].id, tileObjData[i].originX, tileObjData[i].originY, tileObjData[i].width, tileObjData[i].height);
  }
}

// Draws the entity data
function drawEntity(id, posX, posY, sizeX, sizeY){

  var offX = posX + entities[id].speedX;
  var offY = posY + entities[id].speedY;
  
  ctx.fillStyle = '#00F';
  ctx.fillRect(offX, offY + sizeX - sizeY, sizeX, sizeY);

  entities[id].xy.x = offX;
  entities[id].xy.y = offY;
}

// Redraws the canvas with the browser framerate
function mainLoop(){
  drawGame(map);

  for(var i = 0; i < entities.length; ++i){
    animateMove(i, entities[i].dir.up, entities[i].dir.down, entities[i].dir.left, entities[i].dir.right);
  }

  window.requestAnimationFrame(function(){
    mainLoop();
  });
}

// Sets the speed, direction, and collision detection of an entity
function animateMove(id, up, down, left, right){

  var prevTile = entities[id].tile;

  if(up){

    var topLeft = {x: entities[id].xy.x, y: entities[id].xy.y};
    var topRight = {x: entities[id].xy.x + entities[id].width - 1, y: entities[id].xy.y};

    if(!map[coordsToTile(topLeft.x, topLeft.y - 1)].state.passable || !map[coordsToTile(topRight.x, topRight.y - 1)].state.passable){
      entities[id].speedY = 0;
    }
    else{
      entities[id].speedY = -1;
    }
  }
  else if(down){

    var bottomLeft = {x: entities[id].xy.x, y: entities[id].xy.y + entities[id].width - 1};
    var bottomRight = {x: entities[id].xy.x + entities[id].width - 1, y: entities[id].xy.y + entities[id].width - 1};

    if(!map[coordsToTile(bottomLeft.x, bottomLeft.y + 1)].state.passable || !map[coordsToTile(bottomRight.x, bottomRight.y + 1)].state.passable){
      entities[id].speedY = 0;
    }
    else{
      entities[id].speedY = 1;
    }
  }
  else{
    entities[id].speedY = 0;
  }

  if(left){

    var bottomLeft = {x: entities[id].xy.x, y: entities[id].xy.y + entities[id].width - 1};
    var topLeft = {x: entities[id].xy.x, y: entities[id].xy.y};

    if(!map[coordsToTile(bottomLeft.x - 1, bottomLeft.y)].state.passable || !map[coordsToTile(topLeft.x - 1, topLeft.y)].state.passable){
      entities[id].speedX = 0;
    }
    else{
      entities[id].speedX = -1;
    }
  }
  else if(right){

    var bottomRight = {x: entities[id].xy.x + entities[id].width - 1, y: entities[id].xy.y + entities[id].width - 1};
    var topRight = {x: entities[id].xy.x + entities[id].width - 1, y: entities[id].xy.y};

    if(!map[coordsToTile(bottomRight.x + 1, bottomRight.y)].state.passable || !map[coordsToTile(topRight.x + 1, topRight.y)].state.passable){
      entities[id].speedX = 0;
    }
    else{
      entities[id].speedX = 1;
    }
  }
  else{
    entities[id].speedX = 0;
  }

  entities[id].tile = coordsToTile(entities[id].xy.x + (entities[id].width / 2), entities[id].xy.y + (tileSize / 2));
  map[entities[id].tile].render.object = id;

  if(prevTile !== entities[id].tile){
    map[prevTile].render.object = false;
  }
}

//////////////////////////////////////
// THIS IS WHERE I'M HAVING TROUBLE //
//////////////////////////////////////
// A function that can be used by an entity to move along a set path
// id = The id of the entity using this function
// path = An array of strings that determine the direction of movement for a single tile
// originPoint = Coordinates of the previous tile this entity was at. This variable seems to be where problems happen with this logic. It should get reset for every tile length moved, but it only gets reset once currently.
// step = The current index of the path array 

function setPath(id, path, originPoint, step){
  if ((entities[id].dir.left  && entities[id].xy.x <= originPoint.x - tileSize) ||    
      (entities[id].dir.right && entities[id].xy.x >= originPoint.x + tileSize) || 
      (entities[id].dir.up    && entities[id].xy.y <= originPoint.y - tileSize) ||
      (entities[id].dir.down  && entities[id].xy.y >= originPoint.y + tileSize)) {
    // Go to the next step in the path array
    step = step + 1;
    if(step >= path.length){
      step = 0;
    }
    // Reset the origin to the current tile coordinates
    originPoint = JSON.parse(JSON.stringify(entities[id].xy));
  }
  
  // Set the direction based on the current index of the path array
  switch(path[step]) {

    case 'up':
      entities[id].dir.up = true;
      entities[id].dir.down = false;
      entities[id].dir.left = false
      entities[id].dir.right = false;
      break;

    case 'down':
      entities[id].dir.up = false;
      entities[id].dir.down = true;
      entities[id].dir.left = false;
      entities[id].dir.right = false;
      break;

    case 'left':
      entities[id].dir.up = false;
      entities[id].dir.down = false;
      entities[id].dir.left = true;
      entities[id].dir.right = false;
      break;

    case 'right':
      entities[id].dir.up = false;
      entities[id].dir.down = false;
      entities[id].dir.left = false;
      entities[id].dir.right = true;
      break;
  };

  window.requestAnimationFrame(function(){
    setPath(id, path, originPoint, step);
  });
}

// Take a tile index and return x,y coordinates
function tileToCoords(tile){

  var yIndex = Math.floor(tile / mapW);
  var xIndex = tile - (yIndex * mapW);

  var y = yIndex * tileSize;
  var x = xIndex * tileSize;
  return {x:x, y:y};
}

// Take x,y coordinates and return a tile index
function coordsToTile(x, y){

  var tile = ((Math.floor(y / tileSize)) * mapW) + (Math.floor(x / tileSize));
  return tile;
}

// Generate a map array with a blank map and 4 walls
function testMap(){
  for(var i = 0; i < (mapH * mapW); ++i){

    // Edges

    if (
      // top
      i < mapW || 
      // left
      (i % mapW) == 0 || 
      // right
      ((i + 1) % mapW) == 0 || 
      // bottom
      i > ((mapW * mapH) - mapW)
    ) {

      map.push(
        {
          id: i,
          render: {
            base: '#D35',
            object: false,
            sprite: false
          },
          state: {
            passable: false
          }
        },
      );

    }
    else{

      // Grass

      map.push(
        {
          id: i,
          render: {
            base: '#0C3',
            object: false,
            sprite: false
          },
          state: {
            passable: true
          }
        },
      );

    }
  }
}

<!DOCTYPE html>
<html>
<head>

  <style>

    body{
      background-color: #000;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #FFF;
      font-size: 18px;
      padding: 0;
      margin: 0;
    }

    main{
      width: 100%;
      max-width: 800px;
      margin: 10px auto;
      display: flex;
      align-items: flex-start;
      justify-content: center;
      flex-wrap: wrap;
    }

    .game{
      width: 1000px;
      height: 1000px;
      position: relative;
    }

    canvas{
      image-rendering: -moz-crisp-edges;
      image-rendering: -webkit-crisp-edges;
      image-rendering: pixelated;
      image-rendering: crisp-edges;
    }

    .game canvas{
      position: absolute;
      top: 0;
      left: 0;
      width: 800px;
      height: 800px;
    }

  </style>
  
</head>
<body>
  
  <main>
    <div class="game">
      <canvas id="save" width="200" height="200" style="z-index: 1;"></canvas>
    </div>
  </main>

</body>
</html>

关于javascript - JS Canvas 运动动画循环，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/57734806/

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java - 程序适用于 for 循环，但不适用于 while 循环？
编辑:我已经在程序的输出中进行了编辑。该程序要求估计给定值 mu。用户给出一个值 mu，同时还提供了四个不等于 1 的不同数字(称为 w、x、y、z)。然后，程序尝试使用 de Jaeger 公式找
Java For 循环 vs While 循环，奇怪的行为和时间性能
我正在编写一个算法，该算法对一个整数数组从末尾到开头执行一个大循环，其中包含一个 if 条件。第一次条件为假时，循环可以终止。因此，对于 for 循环，如果条件为假，它会继续迭代并进行简单的变量更改
java - While 循环 vs For 循环，哪个更节省内存!
现在我已经习惯了在内存非常有限的情况下进行编程，但我没有答案的一个问题是:哪个内存效率更高；- for(;;) 或 while() ？还是它们可以平等互换？如果有的话，还要对效率问题发表评论! 最佳答
java - 一个 while 循环，其中包含一个 if 语句和一个 for 循环
这个问题已经有答案了: How do I compare strings in Java? (23 个回答) 已关闭 8 年前。我正在尝试创建一个小程序，我可以在其中读取该程序的单词。如果单词有 6
python - 弹出索引超出范围 - 作业(列表，for 循环，while 循环)
这个问题在这里已经有了答案: python : list index out of range error while iteratively popping elements (12 个答案) 关
java - JOptionPane.showInputDialog 循环(使用 do while 循环)
我正在尝试向用户请求 4 到 10 之间的整数。如果他们回答超出该范围，它将进入循环。当用户第一次正确输入数字时，它不会中断并继续执行 else 语句。如果用户在 else 语句中正确输入数字，它将正
php - 嵌套的 foreach 循环，break inside 循环
我尝试创建一个带有嵌套 foreach 循环的列表。第一个循环是循环一些数字，第二个循环是循环日期。我想给一个日期写一个数字。所以还有另一个功能来检查它。但结果是数字多次写入日期。 Out 是这样的:
java - 在 while 循环(或 for 循环)内创建一个数组，然后在外部使用该数组
我想要做的事情是使用循环创建一个数组，然后在另一个类中调用该数组，这不会做，也可能永远不会做。解决这个问题最好的方法是什么？我已经寻找了所有解决方案，但它们无法编译。感谢您的帮助。 import ja
php - 嵌套的 foreach 循环，break inside 循环
我尝试创建一个带有嵌套 foreach 循环的列表。第一个循环是循环一些数字，第二个循环是循环日期。我想给一个日期写一个数字。所以还有另一个功能来检查它。但结果是数字多次写入日期。 Out 是这样的:
c - 如何将 'convert' 两个(for 循环)转为一个(while 循环)？
我正在模拟一家快餐店三个多小时。这三个小时分为 18 个间隔，每个间隔 600 秒。每个间隔都会输出有关这 600 秒内发生的情况的统计信息。我原来的结构是这样的: int i; for (i=0;
javascript - ie javascript for in 循环 vs chrome for in 循环
这个问题已经有答案了: IE8 for...in enumerator (3 个回答) How do I check if an object has a specific property in J
java - 编程语言中的 for 循环 VS while 循环，c++/java？
哪个对性能更好？这可能与其他编程语言不一致，所以如果它们不同，或者如果你能用你对特定语言的知识回答我的问题，请解释。我将使用 c++ 作为示例，但我想知道它在 java、c 或任何其他主流语言中的工
c++ - C++11 段错误中基于范围的 for 循环，但不是常规 for 循环
这个问题不太可能帮助任何 future 的访问者；它只与一个小的地理区域、一个特定的时间点或一个非常狭窄的情况有关，这些情况并不普遍适用于互联网的全局受众。为了帮助使这个问题更广泛地适用，visit
c - while 循环(和 for 循环)上的 scanf 错误，永远扫描
我是 C 编程和编写代码的新手，以确定 M 测试用例的质因数分解。如果我一次只扫描一次，该功能本身就可以工作，但是当我尝试执行 M 次时却惨遭失败。我不知道为什么 scanf() 循环有问题。 in
javascript - 进行修改时应出现 'for-of' 循环，而不是 'for' 循环
这个问题已经有答案了: JavaScript by reference vs. by value [duplicate] (4 个回答) 已关闭 3 年前。我在使用 TSlint 时遇到问题，并且理
javascript - 为 Charts.js 添加 for 循环/foreach 循环
我尝试在下面的代码中添加 foreach 或 for 循环，以便为 Charts.js 创建多个数据集。这将允许我在此折线图上创建多条线。我有一个 PHP 对象，我可以对其进行编码以稍后填充变量，但

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