PHP 基础篇 - PHP 错误级别详解

122 阅读 0 评论 81 点赞

我是靠谱客的博主开放玉米，这篇文章主要介绍PHP 基础篇 - PHP 错误级别详解，现在分享给大家，希望可以做个参考。

2019独角兽企业重金招聘Python工程师标准>>>

一、前言

最近经常看到工作 2 年左右的童鞋写的代码也会出现以静态方法的形式调用非静态方法，这是个 Deprecated 级别的语法错误，代码里不应该出现的。对方很郁闷，说：为什么我的环境可以正常运行呢？

二、详解

代码会不会报错，以及你能不能看到报错信息由 PHP 配置中以下两个参数影响，目前线上主流的配置如下（php.ini 文件中）：

复制代码

1
2
3
error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT
display_errors = Off

下面详细介绍这两个参数：

1. error_reporting

首先来说说 PHP 的错误级别，代码会不会报错由 error_reporting 参数决定，PHP 的错误级别种类如下（点击查看中文版）：

复制代码

E_ALL             - All errors and warnings (includes E_STRICT as of PHP 5.4.0)
E_ERROR           - fatal run-time errors
E_RECOVERABLE_ERROR  - almost fatal run-time errors
E_WARNING         - run-time warnings (non-fatal errors)
E_PARSE           - compile-time parse errors
E_NOTICE          - run-time notices (these are warnings which often result
                    from a bug in your code, but it's possible that it was
                    intentional (e.g., using an uninitialized variable and
                    relying on the fact it is automatically initialized to an
                    empty string)
E_STRICT          - run-time notices, enable to have PHP suggest changes
                    to your code which will ensure the best interoperability
                    and forward compatibility of your code
E_CORE_ERROR      - fatal errors that occur during PHP's initial startup
E_CORE_WARNING    - warnings (non-fatal errors) that occur during PHP's
                    initial startup
E_COMPILE_ERROR   - fatal compile-time errors
E_COMPILE_WARNING - compile-time warnings (non-fatal errors)
E_USER_ERROR      - user-generated error message
E_USER_WARNING    - user-generated warning message
E_USER_NOTICE     - user-generated notice message
E_DEPRECATED      - warn about code that will not work in future versions
                    of PHP
E_USER_DEPRECATED - user-generated deprecation warnings

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
E_ALL             - All errors and warnings (includes E_STRICT as of PHP 5.4.0)
E_ERROR           - fatal run-time errors
E_RECOVERABLE_ERROR  - almost fatal run-time errors
E_WARNING         - run-time warnings (non-fatal errors)
E_PARSE           - compile-time parse errors
E_NOTICE          - run-time notices (these are warnings which often result
                    from a bug in your code, but it's possible that it was
                    intentional (e.g., using an uninitialized variable and
                    relying on the fact it is automatically initialized to an
                    empty string)
E_STRICT          - run-time notices, enable to have PHP suggest changes
                    to your code which will ensure the best interoperability
                    and forward compatibility of your code
E_CORE_ERROR      - fatal errors that occur during PHP's initial startup
E_CORE_WARNING    - warnings (non-fatal errors) that occur during PHP's
                    initial startup
E_COMPILE_ERROR   - fatal compile-time errors
E_COMPILE_WARNING - compile-time warnings (non-fatal errors)
E_USER_ERROR      - user-generated error message
E_USER_WARNING    - user-generated warning message
E_USER_NOTICE     - user-generated notice message
E_DEPRECATED      - warn about code that will not work in future versions
                    of PHP
E_USER_DEPRECATED - user-generated deprecation warnings

其中 WARNING、NOTICE、DEPRECATED 等错误级别会抛出一个错误，但不会终止程序运行。

2. display_errors

再来看一下 display_errors 参数，该参数是是否展示错误信息，只有开启才会显示错误信息（值可以为 on|off、true|false、1|0）。

开发环境最好设置为开启，尽早发现问题，但生产环境一定要关闭。（点击查看中文版官方文档）

3. 问题演示

下面使用 PHP 的运行时配置，改变 PHP 的 error_reporting 和 display_errors，演示上面的问题。代码如下：

复制代码

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
<?php

// error_reporting(E_ALL & ~E_DEPRECATED & ~E_STRICT);  // 该级别下面的代码不会抛出错误
error_reporting(E_ALL & ~E_NOTICE);
ini_set("display_errors", "on");

class Foo
{
    public function test()
    {
        echo 'test';
    }
}

Foo::test();