post上传文件, content-length 与实际获取的大小不相符

Question

form表单上传文件,

Accept:text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Accept-Encoding:gzip, deflate, br
Accept-Language:zh-CN,zh;q=0.8
Cache-Control:max-age=0
Connection:keep-alive
Content-Length:1495
Content-Type:multipart/form-data; boundary=----WebKitFormBoundaryA0iAa0dqm6ZugY1G
Host:127.0.0.1:8899
Origin:http://127.0.0.1:8899
Referer:http://127.0.0.1:8899/file/file.html
Upgrade-Insecure-Requests:1
User-Agent:Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.81 Safari/537.36

可是body中是经过编码的数据

------WebKitFormBoundaryA0iAa0dqm6ZugY1G
Content-Disposition: form-data; name="file"; filename="2.jpg"
Content-Type: image/jpeg


------WebKitFormBoundaryA0iAa0dqm6ZugY1G
Content-Disposition: form-data; name="submit"

Submit
------WebKitFormBoundaryA0iAa0dqm6ZugY1G--

Content-Length与实际body长度不符合, 那么假如我上传了一个大文件, 比如5M, 我在服务器端想要循环读取1M, 该怎么做呢 ?

Answer 1

Content-Length是http传递参数的计算，不止你的文件。你要循环，应该要按照你实际接收到的文件大小来处理。