The object-oriented (iv) Inheritance supplement of PHP's learning notes

Before saying that each time you create a new object, the __construct method is executed first, then when inheriting, do you first execute the _construct method of the parent class and then execute the subclass __construct method?
Let's do an experiment:

classFather{publicfunction__construct(){echo"father has constructed";    }}classChild{publicfunction__construct(){echo"child has constructed";    }}$cnew Child();

The output results are as follows:
Child have constructed
Explains that the __construct method of the parent class was not called when the subclass was created, which is why this is a mechanism for rewriting (overwrite) in PHP, where the constructor of a subclass actually overrides the constructor of the parent class. The constructor for the subclass is executed.
So what happens if the subclass doesn't write the __construct method? Let's experiment:

classFather{publicfunction__construct(){echo"father has constructed";    }}classChild{publicfunctionshow(){echo"dd";    }}$cnew Child();$c->show();输出结果为：dd

;

The output is: DD
Indicates that the __construct () of the parent class is not inherited.

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The above describes the PHP learning notes Object-oriented (iv) Inheritance supplement, including aspects of the content, I hope to be interested in PHP tutorial friends helpful.

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