uni-app WeChat applet to view pdf in base64 file stream format

environment:

uni-app WeChat applet

Description of Requirement:

The front-end requests the back-end interface, the back-end returns the pdf file stream in base64 format , and the front-end obtains the data to open and view the pdf

Code:

1. Add interface response header configuration

responseType: 'arraybuffer' 

2. Use the WeChat file management system to write the base64 format file stream returned by the backend interface to the mobile phone, and then open the preview

// 调用获取 pdf 文件流接口
await getReportDoc({ ...params }).then((data) => {
  const fs = uni.getFileSystemManager()
  const filePath = wx.env.USER_DATA_PATH + '/' + Date.now() + '.pdf'   // wx.env.USER_DATA_PATH 为微信提供的保存文件路径
  fs.writeFile({
    filePath,
    data: wx.base64ToArrayBuffer(data.data.replace(/[\r\n]/g, '')),  // 将 base64 转为 arrayuffer
    success (res) {
      uni.openDocument({
        showMenu: true,
        fileType: 'pdf',
        filePath,
        success: function (res) {
          console.log('打开文档成功')
        }
      })
    },
    fail (err) {
      console.log('错误', err)
    }
  })
})

Here, the applet does not support Blob, so the response type responseType cannot be set to Blob. I checked a lot, and the above code is effective. If there are other ways, welcome to add