{"id":3304,"date":"2025-03-29T15:17:41","date_gmt":"2025-03-29T07:17:41","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=3304"},"modified":"2025-03-29T15:17:41","modified_gmt":"2025-03-29T07:17:41","slug":"c-%e5%a4%9a%e6%80%81%ef%bc%88polymorphism%ef%bc%89","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/03\/29\/c-%e5%a4%9a%e6%80%81%ef%bc%88polymorphism%ef%bc%89\/","title":{"rendered":"C++ \u591a\u6001\uff08Polymorphism\uff09"},"content":{"rendered":"\n<p>\u591a\u6001\u662f\u9762\u5411\u5bf9\u8c61\u7f16\u7a0b\u7684\u6838\u5fc3\u7279\u6027\u4e4b\u4e00\uff0c\u5b83\u4f7f\u5f97\u5bf9\u8c61\u53ef\u4ee5\u901a\u8fc7\u540c\u4e00\u63a5\u53e3\u4ee5\u4e0d\u540c\u7684\u65b9\u5f0f\u8868\u73b0\u3002\u591a\u6001\u5141\u8bb8\u6211\u4eec\u901a\u8fc7\u7236\u7c7b\u7684\u6307\u9488\u6216\u5f15\u7528\u6765\u8c03\u7528\u5b50\u7c7b\u7684\u51fd\u6570\u3002C++ \u4e2d\u7684\u591a\u6001\u4e3b\u8981\u5206\u4e3a\u4e24\u79cd\u7c7b\u578b\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u7f16\u8bd1\u65f6\u591a\u6001\uff08\u9759\u6001\u591a\u6001\uff09<\/strong>\uff1a\u901a\u8fc7\u51fd\u6570\u91cd\u8f7d\u548c\u8fd0\u7b97\u7b26\u91cd\u8f7d\u5b9e\u73b0\u3002<\/li>\n\n\n\n<li><strong>\u8fd0\u884c\u65f6\u591a\u6001\uff08\u52a8\u6001\u591a\u6001\uff09<\/strong>\uff1a\u901a\u8fc7\u7ee7\u627f\u548c\u865a\u51fd\u6570\u5b9e\u73b0\u3002<\/li>\n<\/ol>\n\n\n\n<p>\u4e0b\u9762\u6211\u4eec\u5206\u522b\u6765\u8be6\u7ec6\u4e86\u89e3\u8fd9\u4e24\u79cd\u591a\u6001\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>1. \u7f16\u8bd1\u65f6\u591a\u6001\uff08\u9759\u6001\u591a\u6001\uff09<\/strong><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>1.1 \u51fd\u6570\u91cd\u8f7d\uff08Function Overloading\uff09<\/strong><\/h3>\n\n\n\n<p>\u51fd\u6570\u91cd\u8f7d\u5141\u8bb8\u5728\u540c\u4e00\u4f5c\u7528\u57df\u5185\u5b9a\u4e49\u591a\u4e2a\u540c\u540d\u51fd\u6570\uff0c\u4f46\u5b83\u4eec\u7684\u53c2\u6570\u4e2a\u6570\u6216\u7c7b\u578b\u4e0d\u540c\u3002\u7f16\u8bd1\u5668\u6839\u636e\u8c03\u7528\u65f6\u7684\u53c2\u6570\u6765\u9009\u62e9\u5bf9\u5e94\u7684\u51fd\u6570\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#include &lt;iostream&gt;\nusing namespace std;\n\nclass Print {\npublic:\n    void display(int x) {\n        cout &lt;&lt; \"Display integer: \" &lt;&lt; x &lt;&lt; endl;\n    }\n\n    void display(double x) {\n        cout &lt;&lt; \"Display double: \" &lt;&lt; x &lt;&lt; endl;\n    }\n};\n\nint main() {\n    Print p;\n    p.display(10);     \/\/ \u8c03\u7528 display(int)\n    p.display(10.5);   \/\/ \u8c03\u7528 display(double)\n    return 0;\n}<\/code><\/pre>\n\n\n\n<p><strong>\u8f93\u51fa\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Display integer: 10\nDisplay double: 10.5<\/code><\/pre>\n\n\n\n<p>\u5728\u7f16\u8bd1\u65f6\uff0c\u7f16\u8bd1\u5668\u6839\u636e\u53c2\u6570\u7684\u7c7b\u578b\u81ea\u52a8\u9009\u62e9\u91cd\u8f7d\u7684 <code>display<\/code> \u51fd\u6570\uff0c\u8fd9\u5c31\u662f\u7f16\u8bd1\u65f6\u591a\u6001\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>1.2 \u8fd0\u7b97\u7b26\u91cd\u8f7d\uff08Operator Overloading\uff09<\/strong><\/h3>\n\n\n\n<p>C++ \u5141\u8bb8\u91cd\u8f7d\u8fd0\u7b97\u7b26\uff0c\u91cd\u8f7d\u7684\u8fd0\u7b97\u7b26\u53ef\u4ee5\u7528\u6765\u81ea\u5b9a\u4e49\u7c7b\u578b\u7684\u5bf9\u8c61\u8fdb\u884c\u5e38\u89c1\u64cd\u4f5c\uff0c\u4f8b\u5982 <code>+<\/code>\u3001<code>-<\/code> \u7b49\u8fd0\u7b97\u7b26\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#include &lt;iostream&gt;\nusing namespace std;\n\nclass Complex {\nprivate:\n    int real, imag;\n\npublic:\n    Complex(int r, int i) : real(r), imag(i) {}\n\n    \/\/ \u91cd\u8f7d + \u8fd0\u7b97\u7b26\n    Complex operator + (const Complex&amp; c) {\n        return Complex(real + c.real, imag + c.imag);\n    }\n\n    void display() const {\n        cout &lt;&lt; \"Real: \" &lt;&lt; real &lt;&lt; \", Imag: \" &lt;&lt; imag &lt;&lt; endl;\n    }\n};\n\nint main() {\n    Complex c1(3, 4), c2(1, 2);\n    Complex c3 = c1 + c2;  \/\/ \u4f7f\u7528\u91cd\u8f7d\u7684 + \u8fd0\u7b97\u7b26\n    c3.display();\n    return 0;\n}<\/code><\/pre>\n\n\n\n<p><strong>\u8f93\u51fa\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Real: 4, Imag: 6<\/code><\/pre>\n\n\n\n<p>\u5728\u6b64\u4f8b\u4e2d\uff0c\u91cd\u8f7d\u7684 <code>+<\/code> \u8fd0\u7b97\u7b26\u5141\u8bb8\u4e24\u4e2a <code>Complex<\/code> \u7c7b\u578b\u7684\u5bf9\u8c61\u8fdb\u884c\u76f8\u52a0\u64cd\u4f5c\uff0c\u8fd9\u79cd\u65b9\u5f0f\u79f0\u4e3a\u7f16\u8bd1\u65f6\u591a\u6001\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>2. \u8fd0\u884c\u65f6\u591a\u6001\uff08\u52a8\u6001\u591a\u6001\uff09<\/strong><\/h2>\n\n\n\n<p>\u8fd0\u884c\u65f6\u591a\u6001\u662f\u6307\u5728\u7a0b\u5e8f\u8fd0\u884c\u65f6\u901a\u8fc7\u57fa\u7c7b\u6307\u9488\u6216\u5f15\u7528\u6765\u8c03\u7528\u6d3e\u751f\u7c7b\u7684\u65b9\u6cd5\u3002C++ \u4e2d\u7684\u8fd0\u884c\u65f6\u591a\u6001\u901a\u8fc7<strong>\u865a\u51fd\u6570<\/strong>\uff08virtual functions\uff09\u5b9e\u73b0\u3002\u865a\u51fd\u6570\u4f7f\u5f97\u7f16\u8bd1\u5668\u80fd\u5728\u8fd0\u884c\u65f6\u6839\u636e\u5bf9\u8c61\u7684\u7c7b\u578b\u51b3\u5b9a\u8c03\u7528\u54ea\u4e2a\u7248\u672c\u7684\u51fd\u6570\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>2.1 \u865a\u51fd\u6570\uff08Virtual Function\uff09<\/strong><\/h3>\n\n\n\n<p>\u865a\u51fd\u6570\u662f\u5728\u57fa\u7c7b\u4e2d\u58f0\u660e\uff0c\u5e76\u4e14\u5728\u6d3e\u751f\u7c7b\u4e2d\u53ef\u4ee5\u88ab\u91cd\u5199\u7684\u51fd\u6570\u3002\u4f7f\u7528\u865a\u51fd\u6570\u65f6\uff0c\u901a\u8fc7\u57fa\u7c7b\u6307\u9488\u6216\u5f15\u7528\u8c03\u7528\u51fd\u6570\u65f6\uff0c\u4f1a\u8c03\u7528\u5b9e\u9645\u5bf9\u8c61\u7684\u51fd\u6570\uff0c\u800c\u4e0d\u662f\u57fa\u7c7b\u4e2d\u7684\u51fd\u6570\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\"><strong>2.1.1 \u793a\u4f8b\uff1a\u865a\u51fd\u6570\u548c\u591a\u6001<\/strong><\/h4>\n\n\n\n<pre class=\"wp-block-code\"><code>#include &lt;iostream&gt;\nusing namespace std;\n\nclass Animal {\npublic:\n    \/\/ \u57fa\u7c7b\u4e2d\u7684\u865a\u51fd\u6570\n    virtual void sound() {\n        cout &lt;&lt; \"Animal makes a sound\" &lt;&lt; endl;\n    }\n};\n\nclass Dog : public Animal {\npublic:\n    \/\/ \u91cd\u5199\u57fa\u7c7b\u7684\u865a\u51fd\u6570\n    void sound() override {\n        cout &lt;&lt; \"Dog barks\" &lt;&lt; endl;\n    }\n};\n\nclass Cat : public Animal {\npublic:\n    \/\/ \u91cd\u5199\u57fa\u7c7b\u7684\u865a\u51fd\u6570\n    void sound() override {\n        cout &lt;&lt; \"Cat meows\" &lt;&lt; endl;\n    }\n};\n\nint main() {\n    Animal* animal1 = new Dog();  \/\/ \u57fa\u7c7b\u6307\u9488\u6307\u5411\u6d3e\u751f\u7c7b\u5bf9\u8c61\n    Animal* animal2 = new Cat();  \/\/ \u57fa\u7c7b\u6307\u9488\u6307\u5411\u6d3e\u751f\u7c7b\u5bf9\u8c61\n\n    animal1-&gt;sound();  \/\/ \u8c03\u7528 Dog \u7c7b\u7684 sound\n    animal2-&gt;sound();  \/\/ \u8c03\u7528 Cat \u7c7b\u7684 sound\n\n    delete animal1;\n    delete animal2;\n    return 0;\n}<\/code><\/pre>\n\n\n\n<p><strong>\u8f93\u51fa\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Dog barks\nCat meows<\/code><\/pre>\n\n\n\n<p>\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c<code>sound()<\/code> \u662f\u4e00\u4e2a\u865a\u51fd\u6570\uff0c\u5728\u57fa\u7c7b <code>Animal<\/code> \u4e2d\u58f0\u660e\uff0c\u5e76\u5728\u6d3e\u751f\u7c7b <code>Dog<\/code> \u548c <code>Cat<\/code> \u4e2d\u91cd\u5199\u3002\u5f53\u6211\u4eec\u901a\u8fc7\u57fa\u7c7b\u6307\u9488\u8c03\u7528 <code>sound()<\/code> \u65f6\uff0c\u7a0b\u5e8f\u4f1a\u5728\u8fd0\u884c\u65f6\u51b3\u5b9a\u8c03\u7528\u54ea\u4e2a\u7248\u672c\u7684\u51fd\u6570\uff0c\u5206\u522b\u8f93\u51fa <code>\"Dog barks\"<\/code> \u548c <code>\"Cat meows\"<\/code>\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>2.2 \u865a\u51fd\u6570\u7684\u5de5\u4f5c\u539f\u7406<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u865a\u51fd\u6570\u8868\uff08vtable\uff09<\/strong>\uff1aC++ \u7f16\u8bd1\u5668\u4e3a\u6bcf\u4e2a\u5305\u542b\u865a\u51fd\u6570\u7684\u7c7b\u751f\u6210\u4e00\u4e2a\u865a\u51fd\u6570\u8868\u3002\u5728\u8fd0\u884c\u65f6\uff0c\u6839\u636e\u5bf9\u8c61\u7684\u5b9e\u9645\u7c7b\u578b\u9009\u62e9\u6b63\u786e\u7684\u51fd\u6570\u7248\u672c\u3002<\/li>\n\n\n\n<li><strong>\u52a8\u6001\u7ed1\u5b9a<\/strong>\uff1a\u901a\u8fc7\u865a\u51fd\u6570\u5b9e\u73b0\u8fd0\u884c\u65f6\u591a\u6001\uff0c\u4e5f\u53eb\u52a8\u6001\u7ed1\u5b9a\uff08Dynamic Binding\uff09\u3002\u865a\u51fd\u6570\u4f7f\u5f97\u51fd\u6570\u8c03\u7528\u7684\u89e3\u6790\u63a8\u8fdf\u5230\u8fd0\u884c\u65f6\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>2.3 \u865a\u51fd\u6570\u7684\u6790\u6784\u51fd\u6570<\/strong><\/h3>\n\n\n\n<p>\u5982\u679c\u4e00\u4e2a\u7c7b\u6709\u865a\u51fd\u6570\uff0c\u5b83\u901a\u5e38\u4e5f\u5e94\u8be5\u6709\u4e00\u4e2a\u865a\u6790\u6784\u51fd\u6570\u3002\u5426\u5219\uff0c\u5f53\u901a\u8fc7\u57fa\u7c7b\u6307\u9488\u5220\u9664\u6d3e\u751f\u7c7b\u5bf9\u8c61\u65f6\uff0c\u53ef\u80fd\u4e0d\u4f1a\u8c03\u7528\u6d3e\u751f\u7c7b\u7684\u6790\u6784\u51fd\u6570\uff0c\u4ece\u800c\u5bfc\u81f4\u8d44\u6e90\u6cc4\u6f0f\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>class Animal {\npublic:\n    virtual ~Animal() {\n        cout &lt;&lt; \"Animal Destructor\" &lt;&lt; endl;\n    }\n};\n\nclass Dog : public Animal {\npublic:\n    ~Dog() {\n        cout &lt;&lt; \"Dog Destructor\" &lt;&lt; endl;\n    }\n};<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>2.4 \u7eaf\u865a\u51fd\u6570\uff08Abstract Function\uff09<\/strong><\/h3>\n\n\n\n<p>\u7eaf\u865a\u51fd\u6570\u662f\u6ca1\u6709\u5b9e\u73b0\u7684\u865a\u51fd\u6570\uff0c\u5b83\u5f3a\u5236\u6d3e\u751f\u7c7b\u5fc5\u987b\u5b9e\u73b0\u8be5\u51fd\u6570\u3002\u5305\u542b\u7eaf\u865a\u51fd\u6570\u7684\u7c7b\u79f0\u4e3a\u62bd\u8c61\u7c7b\uff0c\u4e0d\u80fd\u5b9e\u4f8b\u5316\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>class Shape {\npublic:\n    virtual void draw() = 0;  \/\/ \u7eaf\u865a\u51fd\u6570\n};\n\nclass Circle : public Shape {\npublic:\n    void draw() override {\n        cout &lt;&lt; \"Drawing Circle\" &lt;&lt; endl;\n    }\n};\n\nint main() {\n    \/\/ Shape shape;  \/\/ \u9519\u8bef\uff0c\u4e0d\u80fd\u5b9e\u4f8b\u5316\u62bd\u8c61\u7c7b\n    Circle c;\n    c.draw();  \/\/ \u8f93\u51fa \"Drawing Circle\"\n    return 0;\n}<\/code><\/pre>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>3. \u591a\u6001\u7684\u5e94\u7528<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u63a5\u53e3\u548c\u62bd\u8c61\u7c7b<\/strong>\uff1a\u591a\u6001\u4f7f\u5f97\u901a\u8fc7\u57fa\u7c7b\u6307\u9488\u6216\u5f15\u7528\u6765\u64cd\u4f5c\u6d3e\u751f\u7c7b\u5bf9\u8c61\u6210\u4e3a\u53ef\u80fd\uff0c\u4ece\u800c\u652f\u6301\u4e0d\u540c\u7c7b\u7684\u7edf\u4e00\u64cd\u4f5c\u3002<\/li>\n\n\n\n<li><strong>\u6269\u5c55\u6027<\/strong>\uff1a\u901a\u8fc7\u7ee7\u627f\u548c\u91cd\u5199\u865a\u51fd\u6570\uff0c\u53ef\u4ee5\u8f7b\u677e\u6269\u5c55\u7a0b\u5e8f\u800c\u4e0d\u9700\u8981\u4fee\u6539\u73b0\u6709\u4ee3\u7801\u3002<\/li>\n\n\n\n<li><strong>\u8bbe\u8ba1\u6a21\u5f0f<\/strong>\uff1a\u8bb8\u591a\u8bbe\u8ba1\u6a21\u5f0f\uff0c\u5982\u7b56\u7565\u6a21\u5f0f\u3001\u5de5\u5382\u6a21\u5f0f\u3001\u547d\u4ee4\u6a21\u5f0f\u7b49\uff0c\u90fd\u4f9d\u8d56\u4e8e\u591a\u6001\u6765\u5b9e\u73b0\u7075\u6d3b\u548c\u53ef\u6269\u5c55\u7684\u4ee3\u7801\u3002<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>4. \u5c0f\u7ed3<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u7f16\u8bd1\u65f6\u591a\u6001<\/strong>\uff1a\u901a\u8fc7\u51fd\u6570\u91cd\u8f7d\u548c\u8fd0\u7b97\u7b26\u91cd\u8f7d\u5b9e\u73b0\u3002<\/li>\n\n\n\n<li><strong>\u8fd0\u884c\u65f6\u591a\u6001<\/strong>\uff1a\u901a\u8fc7\u865a\u51fd\u6570\u5b9e\u73b0\uff0c\u5141\u8bb8\u901a\u8fc7\u57fa\u7c7b\u6307\u9488\u6216\u5f15\u7528\u8c03\u7528\u6d3e\u751f\u7c7b\u7684\u51fd\u6570\u3002<\/li>\n\n\n\n<li><strong>\u865a\u51fd\u6570<\/strong>\uff1a\u4f7f\u5f97\u51fd\u6570\u8c03\u7528\u7684\u89e3\u6790\u63a8\u8fdf\u5230\u8fd0\u884c\u65f6\uff0c\u4ece\u800c\u5b9e\u73b0\u52a8\u6001\u7ed1\u5b9a\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u591a\u6001\u662f\u9762\u5411\u5bf9\u8c61\u7f16\u7a0b\u7684\u4e00\u4e2a\u91cd\u8981\u7279\u6027\uff0c\u5b83\u4f7f\u5f97\u4ee3\u7801\u66f4\u5177\u53ef\u6269\u5c55\u6027\u548c\u7075\u6d3b\u6027\u3002\u901a\u8fc7\u7ee7\u627f\u548c\u865a\u51fd\u6570\u673a\u5236\uff0c\u6211\u4eec\u53ef\u4ee5\u5b9e\u73b0\u4e0d\u540c\u7c7b\u578b\u5bf9\u8c61\u7684\u7edf\u4e00\u64cd\u4f5c\uff0c\u800c\u4e0d\u9700\u8981\u5173\u5fc3\u5b83\u4eec\u7684\u5177\u4f53\u7c7b\u578b\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u591a\u6001\u662f\u9762\u5411\u5bf9\u8c61\u7f16\u7a0b\u7684\u6838\u5fc3\u7279\u6027\u4e4b\u4e00\uff0c\u5b83\u4f7f\u5f97\u5bf9\u8c61\u53ef\u4ee5\u901a\u8fc7\u540c\u4e00\u63a5\u53e3\u4ee5\u4e0d\u540c\u7684\u65b9\u5f0f\u8868\u73b0\u3002\u591a\u6001\u5141\u8bb8\u6211\u4eec\u901a\u8fc7\u7236\u7c7b\u7684\u6307\u9488\u6216\u5f15\u7528 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":3305,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[81],"tags":[],"class_list":["post-3304","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-c-"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3304","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=3304"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3304\/revisions"}],"predecessor-version":[{"id":3306,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3304\/revisions\/3306"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media\/3305"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=3304"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=3304"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=3304"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}