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dungtv Explainer
Asked At: 1628499743000 In: Programming
dungtv Explainer Asked At: 1628499743000 In: Programming
Khi nào thì lớp cha cast được thành lớp con?
Khi nào thì lớp cha cast được thành lớp con?
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tvd12 Enlightened
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tvd12 Enlightened
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Ví dụ mình có 2 lớp thế này: 

class A {
    // do something
}

class B extends A {
    // do something
}

Thì khi và chỉ khi mình khai báo là A a = new B(); thì mình mới cast được là B b = (B)a; thôi em ạ

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