corssorigin.js

    async initImg (url) {
      const img = new Image()

      // ios 9 base64 设置会报错,去掉
      if (!url.startsWith('data:image')) {
        img.setAttribute('crossOrigin', 'Anonymous')
      }
      img.src = url
      await new Promise(resolve => {
        img.onload = () => {
          resolve(img)
        }
      })
      return img
    },