Additional: [urlencoder.encode (string to be encoded, "encoding method");] (what is it?; why do we use this to encode when we set values in cookies?) (to be improved...)

explain ：

（1） Why did you write this blog ？： stay 【51： The fifth chapter ： Development admin management service ：4： Development 【 newly added admin account number , Interface 】;】 when , Find out ：

          ●  When the administrator logs in , We put the administrator's atoken、aid、aname Set in cookie; then , In the setting, enter cookie When , Will use 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 Transcoding ;

          ●  however , We're setting up aname When , If aname If there is Chinese in it , It will turn Chinese into " The statement "（PS： In fact, it's garbled here , It's not reasonable to ）;

          ●  then , Facing the above situation , My first thought is ： We ask cookie When setting the value in , If you encounter " String containing Chinese ", We don't use 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 Set the encoding method ;;; however , And worry about doing so , It may lead to other unpredictable consequences ;

（2） therefore , This blog mainly solves the following problems ：

          ● problem 1：【URLEncoder.encode( String to be encoded , " Encoding mode ");】 What is it , What does it do ;

          ●  problem 2： be nice with yourself , We set up cookie When , Why do I have to use 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 Set the encoding method ？

（3） The articles referenced in this blog are ：

          ●【 Why urlencode()】, The author of this article is 【yanlei】;

          ●【 Do you really understand URLEncode Do you ？】, The author of this article is 【xiaxveliang】;

Catalog

One ： problem 1：【URLEncoder.encode( String to be encoded , " Encoding mode ");】 What is it , What does it do ; 

1. Reference article 1： Why URLEncoder？

2. Reference article 2： Do you really understand URLEncode Do you ？

Two ： problem 2： be nice with yourself , We set up cookie When , Why do I have to use 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 Set the encoding method ？

1. problem ;

2. analysis ;

3. Solutions ;

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（1） I have encountered many places that need to set the coding method before ： For example, the garbled code in the request , Garbled code in response ,HTML And the garbled code in the front-end static file , When the front and back end interact JSON The mess of ,Tomcat The mess of , The coding method of the compiler, and so on ; These problems , Want to solve , There are clear solutions , There's nothing to repeat ;

（2） then , What we meet here is URLEncoder.encode();

One ： problem 1：【URLEncoder.encode( String to be encoded , " Encoding mode ");】 What is it , What does it do ; 

1. Reference article 1： Why URLEncoder？

Reference from 【 Why urlencode()】, The author of this article is 【yanlei】;

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Through the measured ,【URLEncoder.encode( String to be encoded , " Encoding mode ");】 It has this effect ;

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namely , Through the description here , There seems to be such a feeling ：

          ●  sometimes , We will hope to pass url, To pass some data ;

          ●  and ,url There are restrictions on the data format , For example, there should be no spaces 、 Cannot share @ character , No Chinese characters ;

          ●  therefore ,【 If we have some characters , Want to attach to url in , To pass on 】+【 Among these characters , The space 、@  character 、 Or Chinese 】 When , You need to check this character first , utilize 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 De coding , To conform to url The format of ;

          ●  then , When coding , It doesn't matter what encoding method is used ; As long as both parties agree ;

2. Reference article 2： Do you really understand URLEncode Do you ？

Reference from 【 Do you really understand URLEncode Do you ？】, The author of this article is 【xiaxveliang】;

……………………………………………………

          ●  The above case , It's easy to understand ;

          ●  of Content-Type The content of , You can refer to 【Servlet And JSP Advanced three ： In the response header Content-Type】、【Content-Type Detailed explanation 】 And so on ;

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thus , I feel that the above is for 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 Introduction to , For the moment , Just " Enough " 了 ; temporary , There is no need to delve too deeply ;

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Two ： problem 2： be nice with yourself , We set up cookie When , Why do I have to use 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 Set the encoding method ？

1. problem ;

As in 【51： The fifth chapter ： Development admin management service ：4： Development 【 newly added admin account number , Interface 】;】 in , As mentioned ; be nice with yourself , We set up cookie When , Why do I have to use 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 Set the encoding method ？

2. analysis ;

（1） In limine , We set it into cookie Yes. uid and utoken; You can refer to 【27： The third chapter ： Developing a pass service ：10：【 register / Sign in 】 Interface ： register / Sign in OK after , Send the user session information （uid,utoken） Save to redis and cookie in ;（ A major point ： Set up cookie）】;

（2） at that time ,uid（ Generated by snowflake Algorithm ） and utoken（ utilize UUID Generated ） There are no special characters 、 Space 、@ 、 Chinese, etc ; therefore , Its course 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 After transcoding , It is constant ;

（3） then , We put uid and utoken Set to cookie In the after , Later, judge whether the user logs in 、 publish || Delete articles 、 When querying the article list and other interfaces , The front end will start from cookie In order to get uid and utoken, Set it into header Request header ; meanwhile , You see uid Set in url in ;

（4） therefore , Blind guess here is the consideration ： Since it is set into cookie Value , The front end may be brought over and put url in ; that , We ask cookie When setting the value in , Simply use it all 【URLEncoder.encode( String to be encoded , " Encoding mode ");】 Code it ;

（5） however , The one size fits all approach above , It came into being. 【51： The fifth chapter ： Development admin management service ：4： Development 【 newly added admin account number , Interface 】;】 Meet in , problem ;

3. Solutions ;

There is already a solution in my heart ; however , Because I'm not sure which solution test is more appropriate , Which solution is more adopted by everyone in actual development ; therefore , Put it on hold for a while ……

For the moment , Keep the status quo first .