Debugging skills and best practices in PHP development

For debugging in PHP development, there are the following tips: 1. Use var_dump() to print variable values ​​and types; 2. Use print_r() to print arrays and objects; 3. Use error_log() to record error messages; 4. Use Xdebug gets rich debugging information. Best practices include: 1. Use exception handling; 2. Enable error reporting; 3. Use a live editor; 4. Use a version control system; 5. Test your code.

Debugging skills and best practices in PHP development

In PHP development, debugging is crucial, it Can help us identify and solve problems in the code. This article will introduce some common debugging techniques and best practices to help you easily locate errors.

Practical case

Suppose we have a PHP script calculate.php, which has a add() function used to calculate two numbers and:

function add($a, $b) {
  return $a + $b;
}

echo add(1, 2); // 3

If we accidentally write the operator as - (subtraction), the script will generate an error:

function add($a, $b) {
  return $a - $b;
}

echo add(1, 2); // -1

Debugging Tips

1. Use the var_dump()

var_dump() function to print the value and type of the variable. This helps us examine the contents of variables, especially when their values ​​are unexpected or difficult to predict.

var_dump(add(1, 2)); // int(3)

2. Use print_r()

print_r() The function is similar to var_dump(), but it is more suitable for printing arrays and objects.

print_r(array(1, 2, 3)); // Array ( [0] => 1 [1] => 2 [2] => 3 )

3. Use the error_log()

error_log() function to write the error message to the error log file . This is useful for logging errors that cannot be caught immediately.

error_log("Error: Invalid argument");

4. Use Xdebug

Xdebug is a popular PHP debugger that provides rich debugging information, including stack traces and real-time inspection of variable values. To use Xdebug, you enable it in PHP.ini and configure the IDE to connect to the Xdebug server.

Best Practices

1. Use exception handling

Exception handling can help you handle and log unexpected errors gracefully.

try {
  add(1, 2);
} catch (Exception $e) {
  echo "Error: " . $e->getMessage();
}

2. Enable error reporting

Make sure PHP is configured to report all errors. This can be achieved by setting error_reporting in PHP.ini.

error_reporting = E_ALL

3. Use a live editor

Many modern IDEs provide a live editor that allows you to see debugging information while editing code. This can significantly improve debugging efficiency.

4. Use a version control system

A version control system such as Git allows you to track code changes and easily roll back to a previous version. This is useful for undoing unexpected changes.

5. Test your code

Regularly testing your code can help you catch bugs early and prevent them from entering production.

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