vue 图片转base 64

// 将图片转换为Base64
imageUrlToBase64(img) {
  // 一定要设置为let，不然图片不显示
  let image = new Image();
  // 解决跨域问题
  image.setAttribute('crossOrigin', 'anonymous');
  let imageUrl = img;
  image.src = imageUrl;
  // image.onload为异步加载
  image.onload = () => {
    this.getImage(image);
  };
},
getImage(image) {
  let canvas = document.createElement('canvas');
  canvas.width = image.width;
  canvas.height = image.height;
  let context = canvas.getContext('2d');
  context.drawImage(image, 0, 0, image.width, image.height);
  let quality = 0.8;
  // 这里的dataurl就是base64类型
  let dataURL = canvas.toDataURL('image/jpeg', quality);
  
},