JS下载网络图片到本地

/**
 * 下载网络图片，支持自定义文件名
 * @param {*} link 图片地址，支持跨域
 * @param {*} name 图片名称，自定义
 */
function downloadImg(link, name = 'photo') {
  const image = new Image();

  // 解决跨域问题
  image.setAttribute('crossOrigin', 'anonymous');

  image.onload = () => {
    const canvas = document.createElement('canvas');
    canvas.width = image.width;
    canvas.height = image.height;

    const context = canvas.getContext('2d');
    context.drawImage(image, 0, 0, image.width, image.height);

    const url = canvas.toDataURL('image/png'); // 图片 base64
    const a = document.createElement('a');
    //  + '.png' 定义文件拓展名、防止因为name中有.号导致.png文件拓展名丢失
    a.download = name + '.png';
    a.href = url;

    const event = new MouseEvent('click');
    a.dispatchEvent(event);
  };

  //加时间戳防止图片缓存报跨域问题
  image.src = link + (link.indexOf('?') > -1 ? '&time=' : '?time=') + new Date().valueOf();
};


//调用 
downloadImg('https://pub.jutuike.com/static/img/logo.c1f008ef.jpg','自定义图片名字')