HTTP protocol [get and post] detailed

HTTP defines the different methods of interacting with the server, the most commonly used are 4, Get, Post, Put, delete,put (Increase), delete (delete), Post (change), Get (check), that is, add and remove changes for Delete and Put almost do not introduce:

1) Get, which is used to get information, note that he just gets and queries the data, that is, it does not modify the data on the server, from this point, it is data security, and later mentioned post it can modify the data, so this is one of the differences.

2) post, it is possible to send a modification request to the server, thus modifying the server, for example, we want to post on the Forum, comments on the blog, this will be used to post, of course, it can only get the data

• GET-Requests data from the specified resource.
• POST-submits the data to be processed to the specified resource get method

  Note that the query string (name/value pair) is sent in the URL of the GET request:

  /test/demo_form.asp?name1=value1&name2=value2

  Some additional comments about the GET request:

  • Get requests can be cached
  • GET requests remain in browser history
  • Get requests can be bookmark-Favorites
  • GET requests should not be used when handling sensitive data
  • Get request has a length limit
  • GET requests should only be used to retrieve data
  • POST method

    Note that the query string (name/value pair) is sent in the HTTP message body of the POST request:

    Post/test/demo_form.asp http/1.1host:w3schools.comname1=value1&name2=value2

    Some additional comments about the POST request:

    • POST requests are not cached
    • POST requests are not persisted in browser history
    • POST cannot be bookmarked
    • POST request has no requirement for data length

    • The data for a GET request is placed in the HTTP header, which is followed by a URL, usually as defined in the following format ( and post is the submitted data in the HTTP body ).

      Login.action?name=hyddd&password=idontknow&verify=%e4%bd%e5%a5%bd

      A, to? To separate URLs and data;

      B, with & to separate the parameters;

      C, if the data is English or digital, sent as is;

      D, if the data is in Chinese or other characters, it is BASE64 encoded.

      2) Get submitted less data, up to 1024B, because the get data is attached to the URL, and the URL will be subject to different circumstances, such as IE limit to 2k+35, and post can transmit more data (theoretically unlimited, but generally will be affected by different environments, such as browser, operating system, server processing power limit, IIS4 can support 80KB,IIS5 can support 100KB).

      3) post security is higher than get, because the parameter data is transmitted in clear text when get, and can also cause Cross-site request forgery attack using get. The post data can be encrypted, but get may be faster.

      So, summarize the following table:

      Operation mode	Data location	Vmcontext	Data security	Length limit	Application Scenarios
      GET	HTTP Header	Plaintext	Not safe	Small length	Querying data
      POST	HTTP body	Can be clear and dense	Safety	Supports large data transfer	modifying data

      • Summarize

        Access HTTP resources with GET and post--- · Get requests submit data placed in the HTTP request protocol header (that is, the URL), while the data submitted by the post is placed in the Entity data, security is relatively high. · The Get method submits only 1024 bytes of data, while Post does not have this limit There are two ways to transfer data in different ways. Flexible operation of Get and post based on different server-defined request access methods.

HTTP protocol [get and post] detailed