How to print error messages in PHP

PHP is a commonly used server-side scripting language. In web development, PHP can provide us with great convenience. However, due to irregular coding, grammatical errors and other reasons, we will inevitably encounter various errors during development. Finding errors correctly and quickly and fixing them is one of the compulsory skills for developers. In this article, I will introduce you to how to print error messages in PHP.

1. Use the error reporting mechanism

PHP provides us with a built-in error reporting mechanism, so use this system as much as possible when writing code, which can be effective to help us locate the error. PHP has three error reporting mechanisms: Notice, Warning and Error. When we look for errors, we can locate them based on the report level. Of course, by default, PHP will output these reports to the server's error log file and will not display them directly on the web page. In order to find the problem in time, we need to print these tips on the web page.

2. Turn on error prompts

Turning on error prompts will not cause the website to crash. On the contrary, it is very necessary for developers. During the process of running the code, if an error occurs, PHP will output an error message to the current page and the program will stop executing. In this way, we can quickly locate the line of code and file location where the error is located so that we can fix it. The following is how to turn on error prompts:

<?php
error_reporting(E_ALL);
ini_set(&#39;display_errors&#39;, &#39;1&#39;);
?>

The above code turns on all error prompts through the PHP built-in function error_reporting(), and the ini_set() function prints the error information to the page. This way you can see the errors that occurred on the page.

3. Use try/catch

try/catch is the exception handling mechanism supported by PHP 5. When an exception occurs within a code block, the program interrupts execution and executes the catch statement. We can write code blocks where exceptions may occur into try statements, and use catch statements to handle these exceptions.

<?php
try {
    //可能会引发错误的代码块
}catch(Exception $e) {
    //捕获到错误后的处理
}
?>

Using try/catch can help us avoid direct program crashes, track error messages, and better discover and solve bugs.

Summary

In development, locating errors is a very important task. The printing of error prompts and related mechanisms can effectively help us find problems. During the development process, we can combine the error reporting mechanism, turn on error prompts, and use try/catch and other methods to locate errors. Enhancing one's own error localization capabilities is crucial to quickly solving practical problems.

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