{"id":2401,"date":"2024-07-19T07:29:08","date_gmt":"2024-07-18T23:29:08","guid":{"rendered":"https:\/\/courtship.top\/?p=2401"},"modified":"2024-07-19T07:29:08","modified_gmt":"2024-07-18T23:29:08","slug":"%e8%99%9a%e5%87%bd%e6%95%b0%e8%a1%a8-%e5%85%a8%e8%a7%a3","status":"publish","type":"post","link":"https:\/\/courtship.top\/index.php\/2024\/07\/19\/%e8%99%9a%e5%87%bd%e6%95%b0%e8%a1%a8-%e5%85%a8%e8%a7%a3\/","title":{"rendered":"\u865a\u51fd\u6570\u8868 \u5168\u89e3"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">\u6982\u8ff0<\/h2>\n\n\n\n<p>\u4e3a\u4e86\u5b9e\u73b0C++\u7684\u591a\u6001\uff0cC++\u4f7f\u7528\u4e86\u4e00\u79cd\u52a8\u6001\u7ed1\u5b9a\u7684\u6280\u672f\u3002\u8fd9\u4e2a\u6280\u672f\u7684\u6838\u5fc3\u662f<strong>\u865a\u51fd\u6570\u8868<\/strong>\uff08\u4e0b\u6587\u7b80\u79f0\u865a\u8868\uff09\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u7c7b\u7684\u865a\u8868<\/h2>\n\n\n\n<p>\u6bcf\u4e2a\u5305\u542b\u4e86\u865a\u51fd\u6570\u7684\u7c7b\u90fd\u5305\u542b\u4e00\u4e2a\u865a\u8868\u3002&nbsp;<br>\u6211\u4eec\u77e5\u9053\uff0c\u5f53\u4e00\u4e2a\u7c7b\uff08A\uff09\u7ee7\u627f\u53e6\u4e00\u4e2a\u7c7b\uff08B\uff09\u65f6\uff0c\u7c7bA\u4f1a\u7ee7\u627f\u7c7bB\u7684\u51fd\u6570\u7684\u8c03\u7528\u6743\u3002\u6240\u4ee5\u5982\u679c\u4e00\u4e2a\u57fa\u7c7b\u5305\u542b\u4e86\u865a\u51fd\u6570\uff0c\u90a3\u4e48\u5176\u7ee7\u627f\u7c7b\u4e5f\u53ef\u8c03\u7528\u8fd9\u4e9b\u865a\u51fd\u6570\uff0c\u6362\u53e5\u8bdd\u8bf4\uff0c\u4e00\u4e2a\u7c7b\u7ee7\u627f\u4e86\u5305\u542b\u865a\u51fd\u6570\u7684\u57fa\u7c7b\uff0c\u90a3\u4e48\u8fd9\u4e2a\u7c7b\u4e5f\u62e5\u6709\u81ea\u5df1\u7684\u865a\u8868\u3002<\/p>\n\n\n\n<p>\u6211\u4eec\u6765\u770b\u4ee5\u4e0b\u7684\u4ee3\u7801\u3002\u7c7bA\u5305\u542b\u865a\u51fd\u6570vfunc1\uff0cvfunc2\uff0c\u7531\u4e8e\u7c7bA\u5305\u542b\u865a\u51fd\u6570\uff0c\u6545\u7c7bA\u62e5\u6709\u4e00\u4e2a\u865a\u8868\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>class A \n{\n    public:\n        virtual void vfunc1();\n        virtual void vfunc2();\n        void func1();\n        void func2();\n    private:\n        int m_data1, m_data2;\n};<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"684\" height=\"468\" src=\"https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344094-330f722ee035ed475389a152c069f1e6.png\" alt=\"\" class=\"wp-image-2406\" srcset=\"https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344094-330f722ee035ed475389a152c069f1e6.png 684w, https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344094-330f722ee035ed475389a152c069f1e6-300x205.png 300w\" sizes=\"auto, (max-width: 684px) 100vw, 684px\" \/><\/figure>\n\n\n\n<figure class=\"wp-block-pullquote\"><blockquote><p><strong>\u865a\u8868\u662f\u4e00\u4e2a\u6307\u9488\u6570\u7ec4\uff0c\u5176\u5143\u7d20\u662f\u865a\u51fd\u6570\u7684\u6307\u9488\uff0c\u6bcf\u4e2a\u5143\u7d20\u5bf9\u5e94\u4e00\u4e2a\u865a\u51fd\u6570\u7684\u51fd\u6570\u6307\u9488<\/strong>\u3002\u9700\u8981\u6307\u51fa\u7684\u662f\uff0c\u666e\u901a\u7684\u51fd\u6570\u5373\u975e\u865a\u51fd\u6570\uff0c\u5176\u8c03\u7528\u5e76\u4e0d\u9700\u8981\u7ecf\u8fc7\u865a\u8868\uff0c\u6240\u4ee5\u865a\u8868\u7684\u5143\u7d20\u5e76\u4e0d\u5305\u62ec\u666e\u901a\u51fd\u6570\u7684\u51fd\u6570\u6307\u9488\u3002<br>\u865a\u8868\u5185\u7684\u6761\u76ee\uff0c\u5373<strong>\u865a\u51fd\u6570\u6307\u9488\u7684\u8d4b\u503c\u53d1\u751f\u5728\u7f16\u8bd1\u5668\u7684\u7f16\u8bd1\u9636\u6bb5<\/strong>\uff0c\u4e5f\u5c31\u662f\u8bf4\u5728\u4ee3\u7801\u7684\u7f16\u8bd1\u9636\u6bb5\uff0c\u865a\u8868\u5c31\u53ef\u4ee5\u6784\u9020\u51fa\u6765\u4e86\u3002<\/p><\/blockquote><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">\u865a\u8868\u6307\u9488<\/h2>\n\n\n\n<p><strong>\u865a\u8868\u662f\u5c5e\u4e8e\u7c7b\u7684\uff0c\u800c\u4e0d\u662f\u5c5e\u4e8e\u67d0\u4e2a\u5177\u4f53\u7684\u5bf9\u8c61\uff0c\u4e00\u4e2a\u7c7b\u53ea\u9700\u8981\u4e00\u4e2a\u865a\u8868\u5373\u53ef<\/strong>\u3002<\/p>\n\n\n\n<p><strong>\u540c\u4e00\u4e2a\u7c7b\u7684\u6240\u6709\u5bf9\u8c61\u90fd\u4f7f\u7528\u540c\u4e00\u4e2a\u865a\u8868\u3002<\/strong><\/p>\n\n\n\n<p><strong>\u4e3a\u4e86\u6307\u5b9a\u5bf9\u8c61\u7684\u865a\u8868\uff0c\u5bf9\u8c61\u5185\u90e8\u5305\u542b\u4e00\u4e2a\u865a\u8868\u7684\u6307\u9488\uff0c\u6765\u6307\u5411\u81ea\u5df1\u6240\u4f7f\u7528\u7684\u865a\u8868\u3002<\/strong>\u4e3a\u4e86\u8ba9\u6bcf\u4e2a\u5305\u542b\u865a\u8868\u7684\u7c7b\u7684\u5bf9\u8c61\u90fd\u62e5\u6709\u4e00\u4e2a\u865a\u8868\u6307\u9488\uff0c\u7f16\u8bd1\u5668\u5728\u7c7b\u4e2d\u6dfb\u52a0\u4e86\u4e00\u4e2a\u6307\u9488\uff0c*__vptr\uff0c\u7528\u6765\u6307\u5411\u865a\u8868\u3002\u8fd9\u6837\uff0c\u5f53\u7c7b\u7684\u5bf9\u8c61\u5728\u521b\u5efa\u65f6\u4fbf\u62e5\u6709\u4e86\u8fd9\u4e2a\u6307\u9488\uff0c\u4e14\u8fd9\u4e2a\u6307\u9488\u7684\u503c\u4f1a\u81ea\u52a8\u88ab\u8bbe\u7f6e\u4e3a\u6307\u5411\u7c7b\u7684\u865a\u8868\u3002<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"940\" height=\"612\" src=\"https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344066-1c799113f1b40b3e7712b2d751bcb0bf.png\" alt=\"\" class=\"wp-image-2404\" srcset=\"https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344066-1c799113f1b40b3e7712b2d751bcb0bf.png 940w, https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344066-1c799113f1b40b3e7712b2d751bcb0bf-300x195.png 300w, https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344066-1c799113f1b40b3e7712b2d751bcb0bf-768x500.png 768w\" sizes=\"auto, (max-width: 940px) 100vw, 940px\" \/><\/figure>\n\n\n\n<p>\u4e00\u4e2a\u7ee7\u627f\u7c7b\u7684\u57fa\u7c7b\u5982\u679c\u5305\u542b\u865a\u51fd\u6570\uff0c\u90a3\u4e2a\u8fd9\u4e2a\u7ee7\u627f\u7c7b\u4e5f\u6709\u62e5\u6709\u81ea\u5df1\u7684\u865a\u8868\uff0c\u6545\u8fd9\u4e2a\u7ee7\u627f\u7c7b\u7684\u5bf9\u8c61\u4e5f\u5305\u542b\u4e00\u4e2a\u865a\u8868\u6307\u9488\uff0c\u7528\u6765\u6307\u5411\u5b83\u7684\u865a\u8868\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u52a8\u6001\u7ed1\u5b9a<\/h2>\n\n\n\n<pre class=\"wp-block-code\"><code>class A {\n    public:\n        virtual void vfunc1();\n        virtual void vfunc2();\n        void func1();\n        void func2();\n    private:\n        int m_data1, m_data2;\n};\n\nclass B : public A \n{\n    public:\n        virtual void vfunc1();\n        void func1();\n    private:\n        int m_data3;\n};\n\nclass C: public B \n{\n    public:\n        virtual void vfunc2();\n        void func2();\n    private:\n        int m_data1, m_data4;\n};<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"898\" src=\"https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344294-3bd3b35ecefd13afa68fd01d4facb5b0-1024x898.png\" alt=\"\" class=\"wp-image-2409\" srcset=\"https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344294-3bd3b35ecefd13afa68fd01d4facb5b0-1024x898.png 1024w, https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344294-3bd3b35ecefd13afa68fd01d4facb5b0-300x263.png 300w, https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344294-3bd3b35ecefd13afa68fd01d4facb5b0-768x674.png 768w, https:\/\/courtship.top\/wp-content\/uploads\/2024\/07\/1721344294-3bd3b35ecefd13afa68fd01d4facb5b0.png 1436w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">\u7236\u7c7b\u7c7b\u6307\u9488\u6307\u5411\u5b50\u7c7b\u7684\u865a\u51fd\u6570\u8c03\u7528<\/h2>\n\n\n\n<p>\u5047\u8bbe\u6211\u4eec\u5b9a\u4e49\u4e00\u4e2a\u7c7bB\u7684\u5bf9\u8c61\u3002\u7531\u4e8ebObject\u662f\u7c7bB\u7684\u4e00\u4e2a\u5bf9\u8c61\uff0c\u6545bObject\u5305\u542b\u4e00\u4e2a\u865a\u8868\u6307\u9488\uff0c\u6307\u5411\u7c7bB\u7684\u865a\u8868\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>int main(){    B bObject;}<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u73b0\u5728\uff0c\u6211\u4eec\u58f0\u660e\u4e00\u4e2a\u7c7bA\u7684\u6307\u9488p\u6765\u6307\u5411\u5bf9\u8c61bObject\u3002\u867d\u7136p\u662f\u57fa\u7c7b\u7684\u6307\u9488\u53ea\u80fd\u6307\u5411\u57fa\u7c7b\u7684\u90e8\u5206\uff0c\u4f46\u662f\u865a\u8868\u6307\u9488\u4ea6\u5c5e\u4e8e\u57fa\u7c7b\u90e8\u5206\uff0c\u6240\u4ee5p\u53ef\u4ee5\u8bbf\u95ee\u5230\u5bf9\u8c61bObject\u7684\u865a\u8868\u6307\u9488\u3002bObject\u7684\u865a\u8868\u6307\u9488\u6307\u5411\u7c7bB\u7684\u865a\u8868\uff0c\u6240\u4ee5p\u53ef\u4ee5\u8bbf\u95ee\u5230B vtbl\u3002\u5982\u56fe3\u6240\u793a\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>int main(){    B bObject;    A *p = &amp; bObject;}<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5f53\u6211\u4eec\u4f7f\u7528p\u6765\u8c03\u7528vfunc1()\u51fd\u6570\u65f6\uff0c\u4f1a\u53d1\u751f\u4ec0\u4e48\u73b0\u8c61\uff1f<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>int main(){    B bObject;    A *p = &amp; bObject;    p-&gt;vfunc1();}<\/code><\/pre>\n\n\n\n<p>\u7a0b\u5e8f\u5728\u6267\u884cp-&gt;vfunc1()\u65f6\uff0c\u4f1a\u53d1\u73b0p\u662f\u4e2a\u6307\u9488\uff0c\u4e14\u8c03\u7528\u7684\u51fd\u6570\u662f\u865a\u51fd\u6570\uff0c\u63a5\u4e0b\u6765\u4fbf\u4f1a\u8fdb\u884c\u4ee5\u4e0b\u7684\u6b65\u9aa4\u3002&nbsp;<br>\u9996\u5148\uff0c\u6839\u636e\u865a\u8868\u6307\u9488p-&gt;__vptr\u6765\u8bbf\u95ee\u5bf9\u8c61bObject\u5bf9\u5e94\u7684\u865a\u8868\u3002\u867d\u7136\u6307\u9488p\u662f\u57fa\u7c7bA*\u7c7b\u578b\uff0c\u4f46\u662f*__vptr\u4e5f\u662f\u57fa\u7c7b\u7684\u4e00\u90e8\u5206\uff0c\u6240\u4ee5\u53ef\u4ee5\u901a\u8fc7p-&gt;__vptr\u53ef\u4ee5\u8bbf\u95ee\u5230\u5bf9\u8c61\u5bf9\u5e94\u7684\u865a\u8868\u3002&nbsp;<\/p>\n\n\n\n<p>\u7136\u540e\uff0c\u5728\u865a\u8868\u4e2d\u67e5\u627e\u6240\u8c03\u7528\u7684\u51fd\u6570\u5bf9\u5e94\u7684\u6761\u76ee\u3002\u7531\u4e8e\u865a\u8868\u5728\u7f16\u8bd1\u9636\u6bb5\u5c31\u53ef\u4ee5\u6784\u9020\u51fa\u6765\u4e86\uff0c\u6240\u4ee5\u53ef\u4ee5\u6839\u636e\u6240\u8c03\u7528\u7684\u51fd\u6570\u5b9a\u4f4d\u5230\u865a\u8868\u4e2d\u7684\u5bf9\u5e94\u6761\u76ee\u3002\u5bf9\u4e8e p-&gt;vfunc1()\u7684\u8c03\u7528\uff0cB vtbl\u7684\u7b2c\u4e00\u9879\u5373\u662fvfunc1\u5bf9\u5e94\u7684\u6761\u76ee\u3002<br>\u6700\u540e\uff0c\u6839\u636e\u865a\u8868\u4e2d\u627e\u5230\u7684\u51fd\u6570\u6307\u9488\uff0c\u8c03\u7528\u51fd\u6570\u3002\u4ece\u56fe3\u53ef\u4ee5\u770b\u5230\uff0cB vtbl\u7684\u7b2c\u4e00\u9879\u6307\u5411B::vfunc1()\uff0c\u6240\u4ee5 p-&gt;vfunc1()\u5b9e\u8d28\u4f1a\u8c03\u7528B::vfunc1()\u51fd\u6570\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u52a8\u6001\u7ed1\u5b9a<\/h2>\n\n\n\n<p>\u7ecf\u8fc7\u865a\u8868\u8c03\u7528\u865a\u51fd\u6570\u7684\u8fc7\u7a0b\u79f0\u4e3a\u52a8\u6001\u7ed1\u5b9a\uff0c\u5176\u8868\u73b0\u51fa\u6765\u7684\u73b0\u8c61\u79f0\u4e3a\u8fd0\u884c\u65f6\u591a\u6001\u3002\u52a8\u6001\u7ed1\u5b9a\u533a\u522b\u4e8e\u4f20\u7edf\u7684\u51fd\u6570\u8c03\u7528\uff0c\u4f20\u7edf\u7684\u51fd\u6570\u8c03\u7528\u6211\u4eec\u79f0\u4e4b\u4e3a\u9759\u6001\u7ed1\u5b9a\uff0c\u5373\u51fd\u6570\u7684\u8c03\u7528\u5728\u7f16\u8bd1\u9636\u6bb5\u5c31\u53ef\u4ee5\u786e\u5b9a\u4e0b\u6765\u4e86\u3002<\/p>\n\n\n\n<p>\u90a3\u4e48\uff0c\u4ec0\u4e48\u65f6\u5019\u4f1a\u6267\u884c\u51fd\u6570\u7684\u52a8\u6001\u7ed1\u5b9a\uff1f\u8fd9\u9700\u8981\u7b26\u5408\u4ee5\u4e0b\u4e09\u4e2a\u6761\u4ef6\u3002<\/p>\n\n\n\n<ul 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