It is not safe to rely on the system's timezone settings

在写php文件上传程序时有时会出现这样的警告：

Upload: 屏幕截图2014-09-28_160214.png
Type: image/png
Size: 66.84765625 Kb
Temp file: D:\Users\Aven\AppData\Local\Temp\php742F.tmp

Warning: move_uploaded_file() [function.move-uploaded-file]: It is not safe to rely on the system‘s timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected ‘UTC‘ for ‘8.0/no DST‘ instead in F:\PHP\upload_file.php on line 26

Warning: move_uploaded_file(upload/屏幕截图2014-09-28_160214.png) [function.move-uploaded-file]: failed to open stream: No such file or directory in F:\PHP\upload_file.php on line 26

Warning: move_uploaded_file() [function.move-uploaded-file]: It is not safe to rely on the system‘s timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected ‘UTC‘ for ‘8.0/no DST‘ instead in F:\PHP\upload_file.php on line 26

Warning: move_uploaded_file() [function.move-uploaded-file]: Unable to move ‘D:\Users\Aven\AppData\Local\Temp\php742F.tmp‘ to ‘upload/屏幕截图2014-09-28_160214.png‘ in F:\PHP\upload_file.php on line 26
Stored in: upload/屏幕截图2014-09-28_160214.png

这是因为PHP所取的时间是格林威治标准时间，所以和你当地的时间会有出入格林威治标准时间和北京时间大概差8个小时左右，我们可以按照下面的方法解决： 
1、在页头使用date_default_timezone_set()设置我的默认时区为北京时间，即 <?php date_default_timezone_set("PRC"); ?>就可以了。 
2、在php.ini中设置date.timezone的值为PRC，设置好以后的为：date.timezone=PRC，同时取消这一行代码的注释，即去掉前面的分号就可以了。

这里选用修改配置文件的方式解决问题：

用Notepad++打开php.ini,

查找“date.timezone”，把语句前的分号去掉，值设置为“PRC”，重启FastCGI服务，问题解决。

It is not safe to rely on the system's timezone settings