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HomeBackend DevelopmentPHP TutorialIntroduction to the specific causes and solutions of garbled characters in MySQL and PHP_PHP Tutorial

The reason why MySQL and PHP produce garbled characters:

◆ The default encoding of MySQL database is utf8, if this encoding is different from your PHP web page Inconsistency may cause MySQL to be garbled;

◆ When creating a table in MySQL, you will be asked to choose an encoding. If this encoding is inconsistent with your web page encoding, it may also cause MySQL to be garbled;

◆ You can choose the encoding when adding fields when creating a table in MySQL. If this encoding is inconsistent with the encoding of your web page, it may also cause MySQL garbled code;

◆ The encoding of the page submitted by the user and the page encoding of the displayed data If they are inconsistent, the PHP page will definitely be garbled;

◆ If the page where the user inputs information is big5 code, but the page where the user input is displayed is gb2312, this will 100% cause the PHP page to be garbled;

◆ The character set of the PHP page is incorrect;

◆ The encoding specified in the PHP connection MySQL database statement is incorrect.

Note:

Many people suspect that MySQL version inconsistency will cause garbled code between MySQL and PHP. I believe you won’t think so after reading this guide.

The text you usually see on some websites may have several encodings. For example, if you see a traditional Chinese character, it may be big5 encoding, or it may be utf-8 encoding, and more likely GB code, yes, that is to say, there are traditional Chinese characters encoded in simplified Chinese, and there are also simplified Chinese characters encoded in traditional Chinese. You must understand this.

If you are making a simplified coded web page, the code is set to GB2312. If visitors from Hong Kong and Taiwan submit traditional Chinese information, it may cause garbled code. The solution:

Change The website encoding is set to utf-8, which is compatible with all characters in the world.

If the website has been running for a long time and has a lot of old data, and the Simplified Chinese settings cannot be changed, it is recommended to set the page encoding to GBK. The difference between GBK and GB2312 is that GBK is better than GB2312 To display more characters, if you want to display traditional characters in simplified code, you can only use GBK.

If you understand clearly the reasons for garbled characters when using MySQL and PHP, then the solution will not be difficult.

Solution to the garbled code generated by MySQL and PHP:

If the code for installing MySQL cannot be changed, many friends buy virtual hosts to build websites and do not have the right to change MySQL. We can skip this step of installing the encoding, because as long as the following steps are correct, the garbled code problem can still be solved.

Modify the database encoding. If the database encoding is incorrect, you can execute the following command in PHPmyadmin:

<ol class="dp-xml"><li class="alt"><span><span>ALTER DATABASE 'test'<br> DEFAULT CHARACTER SET <br>utf8 COLLATE utf8_bin </span></span></li></ol>

The above command is to set the encoding of the test database to utf8.

Modify the encoding of the table:

<ol class="dp-xml"><li class="alt"><span><span>ALTER TABLE 'category' <br>DEFAULT CHARACTER SET <br>utf8 COLLATE utf8_bin </span></span></li></ol>

The above command is to change the encoding of a table category to utf8.

Modify the field encoding:

<ol class="dp-xml"><li class="alt"><span><span>ALTER TABLE 'test'<br> CHANGE 'dd' 'dd' VARCHAR( 45 ) <br>CHARACTER SET utf8 COLLATE utf8_bin NOT NULL </span></span></li></ol>

The above command is to change the field encoding of dd in the test table to utf8.

If this situation is easy to solve, just check the page and modify the charset of the source file.

In this case, you can also modify the page charset.

in the statement connecting to the database.

<ol class="dp-xml">
<li class="alt"><span><span>mysql_connect('localhost','user','password'); </span></span></li>
<li class="alt"><span><span>mysql_select_db('my_db'); </span></span></li>
<li class="alt"><span><span>mysql_query("set names utf8;"); <br>//select 数据库之后加多这一句 </span></span></li>
</ol>

In order to avoid the occurrence of garbled characters on the PHP page, the first sentence of the PHP page

<ol class="dp-xml"><li class="alt"><span><span>header("content-type:text/html; </span><span class="attribute">charset</span><span>=</span><span class="attribute-value">utf</span><span>-8"); <br>//强行指定页面的编码,以避免乱码 </span></span></li></ol>

Note: After modifying according to the above method, you can only ensure that your newly inserted data will not cause MySQL and PHP produce garbled codes. For example: If the data submitted by your user is BIG5, but you want to use the above method to change it to be displayed correctly on the GB2312 web page, it is impossible. This kind of transformation of the text code can only be done through Write another program to solve it.


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