为啥要整理下php的报错机制？
一门语言懂了报错机制，就可以处理复杂的异常或错误代码了。提高功力
设置php错误显示等级
ini_set('display_errors', 1);
#
实力调试出错误
Warning
警告
Warning: Invalid argument supplied for foreach() in /data/www/sf-plearnu-local/web/3.php on line 9
ini_set('display_errors', 1);
foreach(1 as $v); 程序编译后。执行出错，报警告错误
Parse
解析
Parse error: syntax error, unexpected end of file in /data/www/sf-plearnu-local/web/3.php on line 10
ini_set('display_errors', 1);
foreach(1 as $v)
// 少了标点符号，在解析代码的时候就错误了
Notice
通知
Notice: Undefined variable: ads in /data/www/sf-plearnu-local/web/3.php on line 9
ini_set('display_errors', 1);
echo $ads;
// 变量未定义，通知错误
Fatal
致命
它话
include 包含的文件不存在的时候，程序报警告错误。代码继续执行
require 包含的文件不存在的时候，程序报致命错误，代码不向下执行
require('321.php');
echo '---';
Warning: require(321.php): failed to open stream: No such file or directory in /data/www/sf-plearnu-local/web/1.php on line 10
Fatal error: require(): Failed opening required '321.php' (include_path='.:/usr/share/pear:/usr/share/php') in /data/www/sf-plearnu-local/web/1.php on line 10
include('321.php');
echo '---';
Warning: include(321.php): failed to open stream: No such file or directory in /data/www/sf-plearnu-local/web/1.php on line 10
Warning: include(): Failed opening '321.php' for inclusion (include_path='.:/usr/share/pear:/usr/share/php') in /data/www/sf-plearnu-local/web/1.php on line 10
---
来源：oschina
链接：https://my.oschina.net/u/2280651/blog/747465