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How To Detect Errors In PHP

How To Detect Errors In PHP

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Nkiru Nwanolue
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6 min read

Programming languages have their strong and weak points. PHP has a bunch of errors, so it's important to know how to solve them.

Errors in programming languages like PHP can cause your programs to malfunction and often go undetected. In this blog post, learn how you can detect any errors in PHP using exception handling - so that you know exactly what to fix!

To begin, you should be aware that some PHP problems block the script from being performed. In contrast, some problems just display error messages with a warning. In order to effectively address a PHP issue in a script, you must first determine the nature of the problem.

There are four types of error messages you should know when dealing with PHP

  • Warning Error

  • Parse Error

  • Notice Error

  • Fatal Error

Warning Error

In PHP, a warning error does not prevent the script from executing. It only alerts you to the presence of a problem. The most typical causes of warning errors are:

  • Failing to include a file or

  • Calling a function with incorrect arguments.

    It's similar to detecting a typo, but it doesn't prevent the PHP code from running, however. It's only a reminder that there are holes in your script.

Parse Error

A parse error happens when a syntax error occurs in the script. Misused or missing symbols in a syntax generate parse problems. The mistake is immediately detected by the compiler, which terminates the script.

Parse errors are triggered by the following:

  • Misspellings
  • Incomplete or extra semicolons or parentheses
  • Unclosed brackets or quotation marks

Notice Error

Notice errors are little mistakes. Similar to warning errors, notice errors also do not prevent the code from running. It just informs you of the fact that there is a problem. Often, the system is unsure if it is an error or a routine code. These errors usually occur when the script requires access to an unknown variable.

Fatal Error

A fatal error occurs when undefined functions and classes are used in PHP code. When a fatal error occurs, the PHP code is terminated and an error message is shown.

Fatal errors occur as a result of the following problems: Startup fatal error (occurs when the system is unable to perform the code during installation) Fatal errors occurred during compilation ( happens when a programmer tries to use nonexistent data) Fatal runtime error (happens while the program is running, causing the code to stop working completely)

Fastest Way to Show All PHP Errors

Add the following lines to your PHP code file to quickly display all PHP errors and warnings:

ini_set ('display_errors', 1);
ini_set ('display_startup_errors', 1);
error_reporting (E_ALL);

The ini_set function overrides the configuration found in the PHP .ini file

The display_errors controls whether errors are shown to the user or hidden. This directive should normally be deactivated after development.

display_startup_errors are differentiated from display errors since display errors do not handle failures that occur during PHP's startup process. The display startup errors directive is also used to detect problems that occur during the PHP startup phase.

error_reporting() This function may be used to report all forms of PHP script errors. Use the option "E ALL & E NOTICE" to report all errors except notices, where E ALL refers to all of the error reporting function's available arguments.

Unfortunately, the display errors and display startup error directives do not handle parsing issues such as missing semicolons and curly brackets. In this case, the PHP ini settings must be altered.

Make the following modifications to the php.ini example file and restart the apache server to display all problems, including parsing errors, in xampp.

display_errors = on

In the PHP.ini file, the display errors directive can be set to "on." This will reveal any problems, including syntax and parsing issues, that would otherwise be hidden by just executing the ini set method in PHP code.

If the application is in production, the display errors directive must be set to "off." The PHP.ini file may be discovered in the phpinfo() function output.

.htaccess Configuration to display PHP Errors

Developers typically have access to directory files. The.htaccess file, which may be found in the project's root or public directory, can also be used to activate or disable the directive for displaying PHP errors.

php_flag display_startup_errors on
php_flag display_errors on

.htaccess contains directives for display_startup_error and display_error messages, similar to what would be added to the PHP code to display PHP problems. The advantage of showing or suppressing error messages in this manner is that development and production may use different .htaccess files, with production suppressing error displays.

Depending on which files you have access to and how you manage deployments and server setups, you may want to alter display errors in .htaccess or your PHP.ini file. Many hosting providers will not allow you to edit the PHP.ini file to enable display errors.

PHP error_reporting() function

Developers can use the PHP error reporting() function to specify which and how many errors should be reported in their applications. Remember that the error reporting directive in the PHP ini settings will be set during runtime by this method.

error_reporting(0);

To erase all errors, warnings, parse messages, and notifications, pass the value zero to the error reporting() method. It would be impossible to put this line of code in each of the PHP scripts. Disabling report messages in the PHP ini or.htaccess file is preferred.

error_reporting(-1);

The error reporting() method also accepts an integer value as an argument. This method may be used in PHP to display errors. There are several forms of mistakes in PHP. The -1 level represents all PHP errors. Even with new levels and constants, the value -1 will continue to operate in future PHP versions.

error_reporting(E_NOTICE);

Even if variables are not specified in PHP, they can be used. This is not advised since undeclared variables might cause problems in the program when used in loops and conditions.

This can also occur when the specified variable differs from the variable used in conditions or loops. If the error reporting() method returns E NOTICE, these undeclared variables will be shown in the web application.

error_reporting(E_ALL & ~E_NOTICE);

The error reporting method allows developers to specify which PHP faults should be shown. Because the "~" character represents "not" or "no," the option ~E NOTICE indicates that notifications should not be shown.

Pay attention to the characters "&" and "|" in the code. The "&" character represents "true for all," while the "|" character represents "true for either." These two characters have the same meaning in PHP: OR and AND.

Because it is more understandable, error reporting E ALL is the most commonly utilized.

Detecting these errors will help you maintain a clean readable code and sort out any display error messages that occur in the process.

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