image使用技巧

图片自动释放资源

Object.defineProperty(HTMLImageElement.prototype, 'src', {
  set: function () {
    // set 只会触发一次
    const that = this as HTMLImageElement
    const handle = () => {
      if (that.src.startsWith('blob:')) {
        URL.revokeObjectURL(that.src);
      }
    }
    that.addEventListener('load', handle)
  }
})