Fabric.js保存自定义属性方法示例

<canvas id="c" width="500" height="400" style="border: 1px solid #ccc;"></canvas>
<button onclick="handleToJSON()">toJSON</button>
<script>
  let canvas = new fabric.Canvas('c')
  let rect = new fabric.Rect({
    width: 30,
    height: 30,
    top: 10,
    left: 10,
    my_id: 'rect01'
  })
  canvas.add(rect)
  function handleToJSON() {
    console.log(canvas.toJSON()) // 序列化，输出JSON
  }
</script>

// 省略部分代码
let canvas = new fabric.Canvas('c')
let rect = new fabric.Rect({
  width: 30,
  height: 30,
  top: 10,
  left: 10,
  my_id: 'rect01'
})
canvas.add(rect)
function handleToJSON() {
  console.log(canvas.toJSON(['my_id'])) // 序列化，输出JSON
}