How to print errors in php server

In the PHP development process, it is very common to encounter errors. How to debug PHP code gracefully is a task that every PHP developer must face. One such means is printing errors.

PHP has a function called error_reporting, which defines how PHP handles errors and warnings. We can use this function to print errors and warnings for better debugging of PHP code.

Here are some ways to print errors and warnings.

1. Use the error_reporting function

In PHP, we can use the error_reporting function to set the error level to be reported. This function has an optional parameter $level, which represents the error level to report. We can set $level to 0 to turn off all error reporting, or to -1 to turn on all error reporting.

For example, we can add the following code at the beginning of the PHP file we want to debug:

<?php
error_reporting(-1);

This will open all error reports, allowing us to quickly find the error and diagnose it.

2. Use the ini_set function

We can also use the ini_set function to set the error level to be reported. This function takes two parameters: $name and $value. $name represents the name of the configuration item to be set, and $value represents the value to be set.

For example, we can add the following code at the beginning of the PHP file we want to debug:

<?php
ini_set('error_reporting', -1);

This will open all error reports, allowing us to quickly find the error and diagnose it.

3. Use the display_errors configuration item

In addition to setting the error reporting level in the PHP code, we can also print errors by modifying the display_errors configuration item in the configuration file.

The display_errors configuration item indicates whether to output error information to the browser. We can set this configuration item to 1 to turn on the error output function, or set it to 0 to turn off the error output function.

For example, we can find the following line in the php.ini file:

display_errors = Off

We can change this configuration item to On:

display_errors = On

This will turn on the error output function , allowing us to see the error message.

4. Set the error_log configuration item

In addition to outputting error information to the browser, we can also write the error information to a log file for later inspection.

PHP has a configuration item error_log, which defines the file path to which error information is output. We can set this configuration item to write error information to a file.

For example, we can find the following line in the php.ini file:

;error_log = php_errors.log

We can uncomment this configuration item and set the log file path:

error_log = /var/log/php_errors.log

This Error messages will be written to the /var/log/php_errors.log file.

In short, printing errors is very important during PHP development. We can use the above methods to print error messages and quickly find and solve problems in PHP code.

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