/**
    * @Event 方法
    * @description: canvas 绘制网格背景
    * */
    drawGrid(element, lineColor, lineStepX, lineStepY, bgColor, bgStepX, bgStepY) {
      const canvas = document.querySelector(element)
      const context = canvas.getContext('2d')
      context.save();
      context.lineWidth = 0.5;
      context.strokeStyle = lineColor;
      context.fillStyle = bgColor;
      context.fillRect(bgStepX, bgStepY, canvas.width, canvas.height);
      context.setLineDash([]);
      context.beginPath();
      for (var i = lineStepX + 0.5; i < canvas.width; i += lineStepX) {
        context.beginPath();
        context.moveTo(i, 0 + 0.5);
        context.lineTo(i, canvas.height + 0.5)
        context.stroke();
      }
      for (var i = lineStepY + 0.5; i < canvas.height; i += lineStepY) {
        context.beginPath();
        context.moveTo(0 + 0.5, i);
        context.lineTo(canvas.width, i);
        context.stroke();
      }
      context.restore();
      context.closePath();
    }

// 使用
 <canvas width="273x"
                        height="153px"
                        style="border:grey 1px solid;"
                        id="myCanvas">
         
       </canvas>



    mounted() {
      this.drawGrid("#myCanvas", "rgba(238,238,238,0.6)", 10, 10, "#333", 0, 0)
    },















    initMyCanvas() {
      const canvas = document.getElementById('myCanvas')
      // 获取绘图上下文
      const ctx = canvas.getContext('2d')
      // 在画布中绘制圆形
      ctx.beginPath()
      ctx.arc(50, 50, 30, 0, 2 * Math.PI)
      ctx.fillStyle = 'red'
      ctx.fill()
    },