今天早晨听到imagerotate()函数不能用，一查是gd库里面的东西。

phpinfo里面显示都正常，显示如下：

gd

GD Support => enabled

GD Version => 2.0 or higher

FreeType Support => enabled

FreeType Linkage => with freetype

FreeType Version => 2.2.1

GIF Read Support => enabled

GIF Create Support => enabled

JPG Support => enabled

PNG Support => enabled

WBMP Support => enabled

使用 var_dump (get_extension_funcs(“gd”)); 检查，确实没有这个函数

看看官方网站的说明吧：

http://cn2.php.net/manual/en/function.imagerotate.php

Note: This function is only available if PHP is compiled with the bundled version of the GD library.

bundled version 就是php自带的GD库，因为当时是自己装的GD库，所以出现问题

以前编译参数：… –with-gd=/www/gd2 …

重新编译 ./configure … –with-gd … (这样就会使用它自己带的GD库)

安装完成，phpinfo

gd
GD Support => enabled
GD Version => bundled (2.0.34 compatible)
FreeType Support => enabled
FreeType Linkage => with freetype
FreeType Version => 2.2.1
GIF Read Support => enabled
GIF Create Support => enabled
JPG Support => enabled
PNG Support => enabled
WBMP Support => enabled
XBM Support => enabled

明白了吧。这样就支持imagerotate函数了，还多了几个其他的函数。

imagefilter …