error_reporting() 设置 php 的报错级别并返回当前级别。
语法 error_reporting(report_level)
如果参数 level 未指定，当前报错级别将被返回。下面几项是 level 可能的值：
值 常量 描述
1 e_error fatal run-time errors. errors that can not be recovered from. execution of the script is halted
2 e_warning non-fatal run-time errors. execution of the script is not halted
4 e_parse compile-time parse errors. parse errors should only be generated by the parser
8 e_notice run-time notices. the script found something that might be an error, but could also happen when running a script normally
16 e_core_error fatal errors at php startup. this is like an e_error in the php core
32 e_core_warning non-fatal errors at php startup. this is like an e_warning in the php core
64 e_compile_error fatal compile-time errors. this is like an e_error generated by the zend scripting engine
128 e_compile_warning non-fatal compile-time errors. this is like an e_warning generated by the zend scripting engine
256 e_user_error fatal user-generated error. this is like an e_error set by the programmer using the php function trigger_error()
512 e_user_warning non-fatal user-generated warning. this is like an e_warning set by the programmer using the php function trigger_error()
1024 e_user_notice user-generated notice. this is like an e_notice set by the programmer using the php function trigger_error()
2048 e_strict run-time notices. php suggest changes to your code to help interoperability and compatibility of the code
4096 e_recoverable_error catchable fatal error. this is like an e_error but can be caught by a user defined handle (see also set_error_handler())
8191 e_all all errors and warnings, except level e_strict (e_strict will be part of e_all as of php 6.0)
例子 任意数目的以上选项都可以用“或”来连接（用 or 或 |），这样可以报告所有需要的各级别错误。例如，下面的代码关闭了用户自定义的错误和警告，执行了某些操作，然后恢复到原始的报错级别：