Several PHP Chinese garbled problems are worth noting

PHP Chinese garbled characters are one of the common problems in PHP development.

PHP Chinese garbled characters sometimes occur in the web page itself, some occur in the process of MySQL interaction, and sometimes are related to the operating system. Here is a summary.

1. The first is the encoding of the PHP web page

The best and fastest solution is that the encoding declared by the page is consistent with the internal encoding of the database. If the page number applied for the page is inconsistent with the internal encoding of the database, set the connection encoding, mysql_query("SET NAMES KKK "); KKK is the connection encoding. It can definitely solve the problem of garbled characters.

1. The encoding of the php file itself and the encoding of the web page should match a. If you want to use gb2312 encoding, then php should output the header: header("Content- Type: text/html; charset=gb2312"), add to the static page, the encoding format of all files is ANSI, available Open Notepad, save as, select encoding as ANSI, and overwrite the source file. b. If you want to use utf-8 encoding, then php should output the header: header("Content-Type: text/html; charset=utf-8"), and add , the encoding format of all files is utf-8. Saving as utf-8 may be a bit troublesome. Generally, utf-8 files will have BOM at the beginning. If you use session, there will be problems. You can use editplus to save. In editplus, go to Tools->Parameter Selection->File-> UTF-8 signature, select Always delete, then save to remove the BOM information.

2. PHP itself is not Unicode, all functions such as substr must be changed to mb_substr (mbstring extension needs to be installed); or use iconv to transcode.

2. Data interaction between PHP and Mysql

The encoding of PHP and the database should be consistent

1. Modify the mysql configuration file my.ini or my.cnf. It is best to use utf8 encoding for mysql [mysql] default-character-set=utf8 [mysqld] default-character-set=utf8 default-storage-engine=MyISAM Add under [mysqld]: default-collation=utf8_bin init_connect='SET NAMES utf8'

2. Add mysql_query(" before the PHP program that needs to perform database operations. set names 'encoding'");, the encoding is consistent with the PHP encoding. If the PHP encoding is gb2312, then the mysql encoding is gb2312. If it is utf-8, then the mysql encoding is utf8, so that there will be no garbled characters when inserting or retrieving data

Three. PHP is related to the operating system. The encoding of Windows and Linux is different. In the Windows environment, if the parameters are utf-8 encoded when calling PHP functions, errors will occur, such as move_uploaded_file(), filesize(), readfile(), etc. These functions are often used when processing uploads and downloads. The following error may occur when calling: Warning: move_uploaded_file()[function.move-uploaded-file]: failed to open stream: Invalid argument in ... Warning: move_uploaded_file()[function.move-uploaded-file]:Unable to move '' to '' in ... Warning: filesize() [function.filesize]: stat failed for ... in ... Warning: readfile( ) [function.readfile]: failed to open stream: Invalid argument in .. Although these errors will not occur when using gb2312 encoding in a Linux environment, the saved file name will be garbled and the file cannot be read. In this case, you can first The parameters are converted into the encoding recognized by the operating system. The encoding conversion can be mb_convert_encoding (string, new encoding, original encoding) or iconv (original encoding, new encoding, string), so that the file name saved after processing will not be garbled, and Files can be read normally, and files with Chinese names can be uploaded and downloaded. In fact, there is a better solution, which is to completely separate from the system, and there is no need to consider the encoding of the system. You can generate a sequence of only letters and numbers as the file name, and save the original name with Chinese characters in the database. In this way, there will be no problem when calling move_uploaded_file(). When downloading, you only need to change the file name to the original name with Chinese characters. Chinese name. The code to implement downloading is as follows header("Pragma: public"); header("Expires: 0"); header("Cache-Component: must-revalidate, post-check=0, pre-check=0"); header( "Content-type: $file_type"); header("Content-Length: $file_size"); header("Content-Disposition: attachment; filename="$file_name""); header("Content-Transfer-Encoding: binary "); readfile($file_path); $file_type is the type of file, $file_name is the original name, and $file_path is the address of the file saved on the service.



Four. Let’s summarize why garbled characters appear. Generally speaking, there are two reasons for the appearance of garbled characters. First, it is due to an error in the encoding (charset) setting, which causes the browser to parse with the wrong encoding, resulting in a messy "Book of Heaven" that fills the screen. Secondly, The file was opened with the wrong encoding and then saved. For example, a text file was originally encoded in GB2312, but was opened and saved in UTF-8 encoding. To solve the above garbled code problem, you first need to know which aspects of development involve coding:



1. File encoding: refers to the encoding in which the page file (.html, .php, etc.) itself is saved. Notepad and Dreamweaver will automatically recognize the file encoding when opening the page, so there will be less problems. However, ZendStudio does not automatically recognize the encoding. It will only open the file in a certain encoding according to the configuration of the preferences. If you accidentally open the file with the wrong encoding while working, and save it after making the modification, garbled characters will appear ( I feel it deeply).



2. Page declaration encoding: In the HTML code HEAD, you can use to tell the browser the web page What encoding is used? Currently, XXX mainly uses GB2312 and UTF-8 in Chinese website development. 3. Database connection encoding: refers to which encoding is used to transmit data to the database when performing database operations. What needs to be paid attention to here. It should not be confused with the encoding of the database itself. For example, MySQL's internal default encoding is latin1 encoding, which means that Mysql stores data in latin1 encoding. Data transmitted to Mysql in other encodings will be converted into latin1 encoding. I know what encoding is used in WEB development. When it comes to encoding, we know the reason for the garbled characters: the above three encoding settings are inconsistent. Since most of the various encodings are ASCII compatible, English symbols will not appear, and Chinese characters will be out of luck.



5. ．Determining some common error situations and solutions:



1. The database uses UTF8 encoding, and the page declaration encoding is GB2312. This is the most common cause of garbled data. At this time, the data is directly SELECTed in the PHP script. Garbled code, you need to use: mysql_query("SET NAMES GBK"); to set the MYSQL connection encoding before querying, and ensure that the page declaration encoding is consistent with the connection encoding set here (GBK is an extension of GB2312) if the page is UTF-. 8 For encoding, you can use: mysql_query("SET NAMES UTF8"); Note that it is UTF8 instead of the commonly used UTF-8. If the encoding declared by the page is consistent with the internal encoding of the database, you do not need to set the connection encoding. Note: In fact, MYSQL. The data input and output is more complicated than what is mentioned above. There are two default encodings defined in the MYSQL configuration file my.ini, namely the default-character-set in [client] and the default-character-set in [mysqld]. Set the encoding used by the client connection and the database internally by default. The encoding we specified above is actually the command line parameter character_set_client when the MYSQL client connects to the server, to tell the MYSQL server what encoding the client data received is. Instead of using the default encoding.



2. The page declaration encoding is inconsistent with the encoding of the file itself. This rarely happens, because if the encoding is inconsistent, what you see when you create the page will be garbled characters. After the release, some minor bugs will be fixed, which is caused by opening the page in the wrong encoding and then saving it. Or you use some FTP software to directly modify files online, such as CuteFTP. Due to incorrect software encoding configuration, the wrong encoding is converted. 3. Some friends who rent virtual hosts still have garbled characters even though the above three encodings are set correctly. For example, if the web page is encoded in GB2312, it is always recognized as UTF-8 when opened by browsers such as IE. The HEAD of the web page has already stated that it is GB2312. After manually changing the browser encoding to GB2312, the page displays normally. The reason is that the server Apache sets the global default encoding of the server and adds AddDefaultCharset UTF-8 in httpd.conf. At this time, the server will first send the HTTP header to the browser, and its priority is higher than the encoding declared in the page. Naturally, the browser will recognize it incorrectly. There are two solutions. Administrators should add AddDefaultCharset GB2312 to their own virtual machine in the configuration file to override the global configuration, or configure it in .htaccess in their own directory. Summary: In a word, the best and fastest way to solve the most garbled Chinese PHP code is to make the encoding declared on the page consistent with the internal encoding of the database. If the page number applied for the page is inconsistent with the internal encoding of the database, set the connection encoding. mysql_query("SET NAMES XXX "); XXX is the connection encoding. It will definitely solve the problem of garbled characters.