fetch & form-data & upload & image file

fetch & form-data & upload & image file

no need multipart/form-data

https://blog.xinshangshangxin.com/2018/12/01/fetch-form-data/

https://zhuanlan.zhihu.com/p/34291688

https://stackoverflow.com/questions/46640024/how-do-i-post-form-data-with-fetch-api

https://stackoverflow.com/questions/17415084/multipart-data-post-using-python-requests-no-multipart-boundary-was-found/17438575

---