Head Information user-agent

' Header ' = ' content-type:application/x-www-form-urlencoded '. "". ' User-agent:post test '. '. ' Content-length: '. strlen ($post _string) +8,

Please explain the meaning of the above remark.
What I know is that when the form is submitted, the encrypted content is not less than 8 bytes long

Reply to discussion (solution)

1.application/x-www-form-urlencoded is a way of expressing commits, which is urlencode, that is, the data submitted is encrypted and the server needs decode to get the data correctly.
2.user-agent: The user agent refers to the browser, its information includes hardware platform, system software, application software and user's personal preference
3.content-length: Content Length, strlen ($post _string) +8, which represents the string length +8 of the post, that is, the minimum also has 8.

Content-type encoded here is the data submitted by application/x-www-form-urlencoded is encoded as a name/value pair
Content-length the size of the transmitted data is the length of the post data
If it is a POST request, you must specify Content-type and Content-length

User-agent is the user agent is the browser as my Chrome user Agent "mozilla/5.0 (Windows NT 5.1) applewebkit/537.36 (khtml, like Gecko) chrome/38.0.212 5.104 safari/537.36 "You're filling it up here.



strlen ($post _string) can not know +8 what to do

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