PHP has been widely used in the field of web development. PHP can not only generate HTML pages, but also create and operate data in binary form, such as images, files, etc. The use of PHP to operate graphics can be achieved through the GD2 function library. You can use the GD2 function library to draw various images and statistical charts on the page. If combined with Ajax technology, you can also create a variety of powerful dynamic charts. The GD2 library is an open, open-source function library for dynamically creating images. Currently, the GD2 library supports multiple image formats such as GIF, PNG, JPEG, WBMP and XBM.
The GD2 function library in PHP5 has been installed by default as an extension. However, in some current versions, you need to set the php.ini file to activate the GD2 function library. Open the php.ini file with a text editor and remove the semicolon in front of the ";extension=php_gd2.dll" statement in the file, then save the modified file and restart the Apache server.
After successfully loading the GD2 library, you can obtain the installation information of the GD2 function library through the phpinfo() statement to verify whether the GD library is successfully installed.
<?php phpinfo(); //输出php配置信息
The above has introduced the understanding of the GD2 function library, including the content of d2 and gd. I hope it will be helpful to friends who are interested in PHP tutorials.
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