Why Am I Getting \'Declaration of childClass::customMethod() should be compatible with that of parentClass::customMethod()\'?

In PHP, Method Declarations Need Compatibility with Parent Methods

PHP programmers might encounter the following error message:

Strict Standards: Declaration of childClass::customMethod() should be compatible with that of parentClass::customMethod()

This error signifies a mismatch between the declaration of a method in a child class and its parent class method declaration.

Possible Causes:

• Different Arguments: The child class's method customMethod() must have the same number, type, and order of arguments as the parent class's customMethod().
• Access Level Difference: The child class's method must have the same or higher access level (public/private/protected) as the parent class's method.

Determining Compatibility:

To understand compatibility, consider the following PHP Manual section:

• [Method Signature Comparison](https://www.php.net/manual/en/language.oop5.basic.php#language.oop5.basic.method-signature)
• [Method Overloading](https://www.php.net/manual/en/language.oop5.overloading.php)

These resources explain the criteria for method compatibility, which includes having the same:

• Method name
• Number and type of arguments
• Return type
• Access level

By addressing these compatibility issues, programmers can eliminate the error and ensure proper inheritance and method overriding.

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