\u6709\u65f6\u5019\u8111\u888b\u77ed\u8def\uff0c\u52a0\u4e0a\u8bb0\u5fc6\u529b\u9000\u5316\uff0c\u5f88\u591a\u5df2\u77e5\u7684\u6982\u5ff5\u53c8\u6a21\u7cca\u6df7\u6dc6\u4e86\u3002\u5509\uff0c\u676f\u5177\u3002
\n\u4eca\u5929\u5c31\u5728\u60f3\u4e00\u4e2a\u62e5\u6709\u865a\u51fd\u6570\u7684\u57fa\u7c7b\uff0c\u5b83\u7684\u5bf9\u8c61\u662f\u4e0d\u662f\u6ca1\u6709vptr\u548cvtable\uff1f\u56e0\u4e3a\u5b83\u672c\u8eab\u5f88\u786e\u5b9a\u4e86\uff0c\u5982\u4e0b\uff1a
\nclass CA
\n{
\npublic:
\n\u00a0virtual void Func1()
\n\u00a0{
\n\u00a0\u00a0printf(“CA::Func1\\n”);
\n\u00a0}
\n};
\nCA a;
\nprintf(“sizeof(a)=%d, sizeof(CA)=%d\\n”, sizeof(a), sizeof(CA));
\na.Func1();
\n\u4e8b\u5b9e\u662fsizeof\u5747\u4e3a4\uff0c\u4e5f\u5c31\u662f\u8bf4\u6709vptr\u548cvtable!\u800ca.Func1\u7684\u8c03\u7528\u4e5f\u786e\u5b9e\u662f\u5f88\u786e\u5b9a\u7684\uff1a
\n00424591\u00a0 lea\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 ecx,[a]
\n00424594\u00a0 call\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 CA::Func1 (41564Ah)
\n\u4f46\u82e5\u4f7f\u7528\u6307\u9488\u8c03\u7528\u5219\uff1a
\nCA *pa = &a;
\n0042D241\u00a0 lea\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 eax,[a]
\n0042D244\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 dword ptr [pa],eax
\npa->Func1();
\n0042D247\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 eax,dword ptr [pa]
\n0042D24A\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 edx,dword ptr [eax]
\n0042D24C\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 esi,esp
\n0042D24E\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 ecx,dword ptr [pa]
\n0042D251\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 eax,dword ptr [edx]
\n0042D253\u00a0 call\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 eax
\n\u5f88\u660e\u663e\u662f\u901a\u8fc7vptr\u548cvtable\u5b9e\u73b0\u7684\u3002\u60f3\u60f3\u591a\u6001\u7684\u6982\u5ff5\u4e5f\u786e\u5b9e\u662f\u865a\u51fd\u6570+\u6307\u9488\/\u5f15\u7528\u7684\u7ed3\u5408\u5b9e\u73b0\u7684\u3002
\n\u56e0\u6b64\u4e00\u4e2a\u7c7b\u53ea\u8981\u62e5\u6709\u865a\u51fd\u6570\u5219\u4e00\u5b9a\u662f\u62e5\u6709vptr\u548cvtable\u7684\uff0c\u7f16\u8bd1\u5668\u53ef\u4ee5\u4e0d\u7528\u533a\u5206\u8fd9\u662f\u4e0d\u662f\u591a\u6001\uff08\u6307\u9488\/\u5f15\u7528\u7684\u5bf9\u8c61\u662f\u57fa\u7c7bCA\u7684\u8fd8\u662f\u5b50\u7c7bCB\u7684\uff09\u6765\u5206\u522b\u751f\u6210\u4ee3\u7801\uff0c\u5982\u4e0b\uff1a
\nCA *pa = &b;
\n0042D264\u00a0 lea\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 eax,[b]
\n0042D267\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 dword ptr [pa],eax
\npa->Func1();
\n0042D26A\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 eax,dword ptr [pa]
\n0042D26D\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 edx,dword ptr [eax]
\n0042D26F\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 esi,esp
\n0042D271\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 ecx,dword ptr [pa]
\n0042D274\u00a0 mov\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 eax,dword ptr [edx]
\n0042D276\u00a0 call\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 eax\u00a0
\n\u53c8\u5728\u60f3\u53e6\u4e00\u4e2a\u95ee\u9898\uff1a\u82e5\u4e00\u4e2a\u62e5\u6709\u865a\u51fd\u6570\u7684\u5b50\u7c7b\u7ee7\u627f\u81ea\u4e00\u4e2a\u62e5\u6709\u865a\u51fd\u6570\u7684\u57fa\u7c7b\uff0c\u5b83\u7684\u5bf9\u8c61\u662f\u4e0d\u662f\u6709\u4e24\u5957vptr\u548cvtable\uff1f\u5982\u4e0b
\nclass CB : public CA
\n{
\npublic:
\n\u00a0virtual void Func2()
\n\u00a0{
\n\u00a0\u00a0printf(“CB::Func2\\n”);
\n\u00a0}
\n};
\n\u7b54\u6848\u662f\u4e0d\u9700\u8981\uff0c\u56e0\u4e3a\u53ef\u4ee5\u901a\u8fc7\u4e00\u5957vptr\u548cvtable\u8c03\u7528\u5230\u5404\u81ea\u7684\u6210\u5458\u51fd\u6570\uff0c\u53ea\u6709\u591a\u91cd\u7ee7\u627f\u65f6\u624d\u4f1a\u6709\u591a\u5957vptr\u548cvtable\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
\u6709\u65f6\u5019\u8111\u888b\u77ed\u8def\uff0c\u52a0\u4e0a\u8bb0\u5fc6\u529b\u9000\u5316\uff0c\u5f88\u591a\u5df2\u77e5\u7684\u6982\u5ff5\u53c8\u6a21\u7cca\u6df7\u6dc6\u4e86\u3002\u5509\uff0c\u676f\u5177\u3002 \u4eca\u5929\u5c31\u5728\u60f3\u4e00\u4e2a\u62e5\u6709\u865a\u51fd\u6570\u7684\u57fa\u7c7b\uff0c\u5b83\u7684\u5bf9 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20],"tags":[],"class_list":["post-1245","post","type-post","status-publish","format-standard","hentry","category-cplusplus"],"_links":{"self":[{"href":"http:\/\/115.29.108.60\/index.php?rest_route=\/wp\/v2\/posts\/1245","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/115.29.108.60\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/115.29.108.60\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/115.29.108.60\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/115.29.108.60\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1245"}],"version-history":[{"count":1,"href":"http:\/\/115.29.108.60\/index.php?rest_route=\/wp\/v2\/posts\/1245\/revisions"}],"predecessor-version":[{"id":1246,"href":"http:\/\/115.29.108.60\/index.php?rest_route=\/wp\/v2\/posts\/1245\/revisions\/1246"}],"wp:attachment":[{"href":"http:\/\/115.29.108.60\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1245"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/115.29.108.60\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1245"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/115.29.108.60\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1245"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}