35 lines
653 B
Markdown
35 lines
653 B
Markdown
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# 类 Const 成员
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类 const 成员为只读变量类型，其初始化需要通过初始化变量列表来完成：
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```cpp
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class ClassA
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{
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public:
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ClassA():Va(-1), Vb(true) { }
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ClassA(int a=-1, bool b=true):Va(a), Vb(b) { }
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cont int Va;
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const bool Vb;
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}
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```
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如果某子类想要在构造时初始化父类的 const 成员，则需要在子类的初始化列表中调用父类的构造函数：
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```cpp
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class ClassA
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{
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public:
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ClassA(int a=-1, bool b=true):Va(a), Vb(b) { }
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cont int Va;
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const bool Vb;
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}
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class ClassB : public ClassA
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{
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ClassB():ClassA(1, false) {}
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ClassB(int a, bool b):ClassA(a, b) {}
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}
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```
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