PHP header solves garbled code problems and other garbled code problems

Reprinted from http://www.jb51.net/article/22501.htm

php header to define a php page as UTF encoding or GBK encoding

The php page is encoded in utf
header("Content-type: text/html; charset=utf-8");
The page in php is encoded in gbk
header("Content-type: text/html; charset=gb2312"); The php page is encoded in big5 Home page of the page
The difference between using header or meta to implement PHP page encoding 1. Page encoding

1. Use Tag setting page encoding
The function of this tag is to declare what character set encoding the client's browser uses to display the page. xxx can be GB2312, GBK, UTF-8 (different from MySQL, MySQL is UTF8), etc. . Therefore, most pages can use this method to tell the browser what encoding to use when displaying this page, so as to avoid encoding errors and causing garbled characters. But sometimes we will find that this sentence still does not work, no matter what. Which one is xxx? The browser always uses the same encoding. I will talk about this later.
Please note that is html information and is just a statement. It works to indicate the server. The HTML information has been transmitted to the browser. 2. header("content-type:text/html; charset=xxx");

The function of this function header() is to send the information in the brackets. Go to the http header.
If the content in the brackets is as mentioned in the article, the function is basically the same as the tag. If you compare it with the first one, you will find that the characters are similar. But the difference is if there is this paragraph. function, the browser will always use the xxx encoding you requested and will never be disobedient, so this function is very useful. Then we have to talk about the difference between HTTPS headers and HTML information:
The https header is a string sent by the server before transmitting HTML information to the browser using the HTTP protocol. Because the meta tag belongs to html information, the content sent by header() reaches the browser first. In simple terms, that is. The priority of header() is higher than meta (I don’t know if I can say this). Adding a php page has both header("content-type:text/html; charset=xxx") and , the browser only recognizes the former http header and not the meta. Of course, this function can only be used in PHP pages.
There is also a question, why does the former It definitely works, but the latter sometimes doesn't work? This is the reason why we want to talk about Apache next.
3. AddDefaultCharset

The conf folder in the Apache root directory contains the entire Apache configuration document. httpd.conf.
Open httpd.conf with a text editor. Line 708 (different versions may be different) has AddDefaultCharset xxx, xxx is the encoding name. The meaning of this line of code: Set the https header of the web page file within the entire server. The character set in is your default xxx character set. With this line, it is equivalent to adding a header("content-type:text/html;" to each file. charset=xxx"). Now you can understand why the browser always uses gb2312 even though the meta setting is utf-8.
If there is header("content-type:text/html; charset=xxx "), change the default character set to the character set you set, so this function will always be useful. If you add a "#" in front of AddDefaultCharset xxx, comment out this sentence, and the page does not contain header("content-type …"), then it’s the meta tag’s turn to come into play. Summary:

Let’s sort
header("content-type:text/html; charset=xxx")
AddDefaultCharset xxx
If you are a web programmer, add a header(" content-type:text/html; charset=xxx"), ensuring that it can be displayed correctly on any server and has strong portability.
As for the sentence AddDefaultCharset xxx, whether it should be commented or not is a matter of opinion. Anyway, I commented it out, but I also need to write header() when writing a page, so that it can be displayed normally on the server.
2. Database encoding
Before querying the database, the PHP program first executes mysql_query("SET NAMES xxxx"); where xxxx is the encoding of your web page (charset=xxxx). If charset=utf8 in the web page, then xxxx =utf8, if charset=gb2312 in the web page, then xxxx=gb2312. Almost all WEB programs have a common code to connect to the database, which is placed in a file. In this file, add mysql_query("set names") will do the trick.
SET NAMES Shows what character set is used in the SQL statement sent by the client. Therefore, the SET NAMES 'utf-8' statement tells the server that "future information from this client will use the character set utf-8." It also specifies the character set for the results that the server sends back to the client. (For example, if you use a SELECT statement, it indicates what character set is used for the column value.)
PHP page encoding is unified
MySQL database encoding, html page encoding, PHP or html file itself encoding must be all consistent .
　1. MySQL database encoding: Specify the encoding (such as gbk_chinese_ci) when creating the database. Do not specify the encoding when creating data tables, creating fields, and inserting data. The encoding of the database will be automatically inherited.
There is also encoding when connecting to the database. After connecting to the database, you can execute
mysql_query('SET NAMES gbk');//Replace gbk with your encoding, such as utf8.
　2. The encoding of the html page refers to the setting of this line:

　3. PHP Or the encoding of the html file itself: Use editplus to open the php file or html file. When saving, select the encoding. If the database and page encoding is gbk, then the encoding here selects ansi; if the database and page encoding is utf-8, then here Also choose utf-8.
　　4. Also note that the data passed in Javascript or Flash is utf-8 encoded. If the database and page encoding is gbk, it must be transcoded and then written to the database.
iconv('utf-8', 'gbk', $content);
5. In the PHP program, you can add a line to specify the encoding of the PHP source program:
header('Content-type: text/html; charset=gbk');

The above introduces the PHP header to solve garbled code problems and other garbled code problems, including the content. I hope it will be helpful to friends who are interested in PHP tutorials.