图片显示（后端返回接口在预览中展示图片，响应无返回）后端返回二进制图片前端乱码解决方案

https://blog.csdn.net/weixin_46801282/article/details/123386264

// base64数据

this.imgSrc = 'data:image/jpg;base64,' + res.payload.imageStr;

解决方案一:<br>后端把图片转码成base64再发送过来router.get('/test', (req, res) => {
  fs.readFile('./test.png', 'binary', function (err, file) {
    if (err) {
      console.log(err)
      return
    } else {
      res.send({
        status: 0,
        message: '调取成功',
        data: Buffer.from(file, 'binary').toString('base64'),
      })
    }
  })
})

解决方案二
 
添加 {responseType: ‘arraybuffer’} 请求头,获取ArrayBuffer类型数据,再转码成base64
 
      axios.get('http://localhost:801/my/test', {
         responseType: 'arraybuffer'
      }).then(res => {
        console.log(res)
         // buffer转译
         console.log(btoa(new Uint8Array(res.data).reduce((data, byte) => data + String.fromCharCode(byte), '')), 'base64');
      })

解决方案三
跟前面方法二一样
添加 {responseType: ‘blob’} 请求头,获取blob类型数据
 
      axios.get('http://localhost:801/my/test', {
         responseType: 'blob'
      }).then(res => {
         console.log(
            res
         )
         const blob = new Blob([res.data])
         var reader = new window.FileReader();
         reader.readAsDataURL(blob);
         reader.onloadend = function () {
            document.querySelector('#img').src = reader.result
         }
      })
　　