{"id":3803,"date":"2021-02-22T22:01:21","date_gmt":"2021-02-22T14:01:21","guid":{"rendered":"http:\/\/blog.coolcoding.cn\/?p=3803"},"modified":"2021-02-22T22:01:21","modified_gmt":"2021-02-22T14:01:21","slug":"effective-c%e7%ac%ac39%e6%9d%a1%ef%bc%9a%e4%bd%bf%e7%94%a8private%e7%bb%a7%e6%89%bf","status":"publish","type":"post","link":"https:\/\/blog.coolcoding.cn\/?p=3803","title":{"rendered":"Effective C++\u7b2c39\u6761\uff1a\u4f7f\u7528private\u7ee7\u627f"},"content":{"rendered":"\n<p><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">1\u3001private\u7ee7\u627f\u7684\u4e24\u6761\u89c4\u5219<\/h2>\n\n\n\n<ul><li>\u89c4\u5219\u4e00\uff1a\u5982\u679cclasses\u4e4b\u95f4\u662fprivate\u7ee7\u627f\u5173\u7cfb\uff0c\u90a3\u4e48\u7f16\u8bd1\u5668\u4e0d\u4f1a\u81ea\u52a8\u5c06\u4e00\u4e2a<code>derived class<\/code>\u5bf9\u8c61\u8f6c\u6362\u4e3a\u4e00\u4e2a<code>base class<\/code>\u5bf9\u8c61\u3002<\/li><li>\u89c4\u5219\u4e8c\uff1a\u7531<code>private base class<\/code>\u7ee7\u627f\u800c\u6765\u7684\u6240\u6709\u6210\u5458\uff0c\u5728<code>derived class<\/code>\u4e2d\u90fd\u4f1a\u53d8\u6210<code>private<\/code>\u5c5e\u6027\uff0c\u7eb5\u4f7f\u5b83\u4eec\u5728<code>base class<\/code>\u4e2d\u539f\u672c\u662f<code>protected<\/code>&nbsp;\u6216<code>public<\/code>\u5c5e\u6027\u3002<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">2\u3001private \u7ee7\u627f\u6240\u63cf\u8ff0\u7684\u5173\u7cfb<\/h2>\n\n\n\n<ul><li><code>private<\/code>\u7ee7\u627f \u610f\u5473\u8fd9<code>implemented-in-terms-of<\/code>&nbsp;\u3002<code>private<\/code>&nbsp;\u7ee7\u627f\u53ea\u662f\u4e00\u79cd\u5b9e\u73b0\u6280\u672f\uff0c\u5b83\u6ca1\u6709\u201c\u8bbe\u8ba1\u201d\u5c42\u9762\u4e0a\u7684\u610f\u4e49\u3002<\/li><li><code>private<\/code>\u7ee7\u627f\u53ea\u6709\u5b9e\u73b0\u90e8\u5206\u88ab\u7ee7\u627f\uff0c\u63a5\u53e3\u5e94\u8be5\u88ab\u5ffd\u7565\u3002<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">3\u3001\u590d\u5408\u4e0eprivate\u7ee7\u627f\u7684\u9009\u62e9<\/h2>\n\n\n\n<h5 class=\"wp-block-heading\">\u7591\u95ee\uff1a<\/h5>\n\n\n\n<p>\u590d\u5408\u548c<code>private<\/code>\u7ee7\u627f\u90fd\u662f\u63cf\u8ff0<code>implemented-in-terms-of<\/code>&nbsp;\u5173\u7cfb\uff0c\u90a3\u4e48\u5728\u7c7b\u8bbe\u8ba1\u65f6\u5e94\u8be5\u4f7f\u7528\u590d\u5408\u8fd8\u662fprivate\u7ee7\u627f\u8be5\u5982\u4f55\u9009\u62e9\u5462\uff1f<\/p>\n\n\n\n<h5 class=\"wp-block-heading\">(1)\u9996\u5148\u5927\u90e8\u5206\u60c5\u51b5\u4e0b\u5e94\u8be5\u5c3d\u53ef\u80fd\u7684\u4f7f\u7528\u590d\u5408\u3002<\/h5>\n\n\n\n<h5 class=\"wp-block-heading\">(2)\u5728\u4e0b\u8ff0\u51e0\u79cd\u60c5\u51b5\u4f7f\u7528private\u7ee7\u627f\uff1a<\/h5>\n\n\n\n<ul><li>\u5f53protected\u6210\u5458\u6216virtual\u51fd\u6570\u7275\u626f\u8fdb\u6765\u7684\u65f6\u5019\u3002(\u7531\u4e8e\u9700\u6c42\u7684\u539f\u56e0\uff0c\u8fd9\u65f6\u6b63\u7edf\u7684\u8bbe\u8ba1)<\/li><li>\u53e6\u4e00\u79cd\u66f4\u6fc0\u8fdb\u7684\u60c5\u51b5\uff1a\u5f53\u57fa\u7c7b\u4e3a\u7a7a\u7c7b\u65f6\uff0c\u53ef\u4ee5\u8d77\u5230\u8282\u7ea6\u5185\u5b58\u7a7a\u95f4\u7684\u4f5c\u7528\u3002(\u5982\u679c\u5ba2\u6237\u5bf9\u4e8e\u5185\u5b58\u7a7a\u95f4\u7684\u8981\u6c42\u6781\u9ad8\u7684\u8bdd\uff0c\u53ef\u4ee5\u91c7\u7528private\u7ee7\u627f\u3002)<\/li><\/ul>\n\n\n\n<p>\u6ce8\u610f\uff1a\u201c<code>empty class<\/code>\u201d\uff1a\u8fd9\u91cc\u7684\u7a7a\u7c7b\u662f\u6307\u53ea\u5305\u542b\uff1a<code>typedefs<\/code>,<code>enums<\/code>,<code>static<\/code>\u6210\u5458\u53d8\u91cf\u6216\u8005<code>non-virtual<\/code>\u51fd\u6570\uff0c\u4e0d\u5305\u542b<code>non-static<\/code>\u6210\u5458\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">4\u3001\u590d\u5408\u4e0eprivate\u7ee7\u627f\u7684\u4f18\u7f3a\u70b9\u6bd4\u8f83<\/h2>\n\n\n\n<ul><li>\u590d\u5408\u8981\u6bd4private\u7ee7\u627f\u590d\u6742\u4e00\u4e9b\u3002<\/li><li>\u590d\u5408\u6bd4private\u7ee7\u627f\u66f4\u5bb9\u6613\u7406\u89e3\u3002<\/li><li>\u590d\u5408\u7684\u8026\u5408\u6027(\u4f9d\u5b58\u6027\uff0c\u9700\u8981\u5305\u542b\u5934\u6587\u4ef6\uff0c\u9700\u8981\u6ce8\u610f\u6587\u4ef6\u52a0\u8f7d\u987a\u5e8f\u7b49\u95ee\u9898\u3002)\u8981\u6bd4private\u7ee7\u627f\u4f4e\u3002\u8fd9\u5bf9\u5927\u578b\u7a0b\u5e8f\u8bbe\u8ba1\u975e\u5e38\u91cd\u8981\u3002<\/li><li>private\u7ee7\u627f\u5728\u67d0\u4e9b\u5bf9\u5185\u5b58\u8981\u6c42\u6bd4\u8f83\u9ad8\u7684\u573a\u5408\u53ef\u4ee5\u8d77\u5230\u8282\u7ea6\u5185\u5b58\u7684\u4f5c\u7528\u3002<\/li><li>\u5b66\u4e60private\u7ee7\u627f\u7684\u53e6\u4e00\u76ee\u7684\u662f\u6269\u5c55\u89e3\u51b3\u95ee\u9898\u7684\u601d\u8def\u3002<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">5\u3001private\u7ee7\u627f\u662f\u5982\u4f55\u505a\u5230\u8282\u7ea6\u5185\u5b58\u7a7a\u95f4\u7684\uff1f<\/h2>\n\n\n\n<p>\u5982\u679c\u4e00\u4e2a\u7c7b\u4e3a \u7a7a\u7c7b\u7684\u8bdd\uff0c\u6309\u9053\u7406\u8bb2\uff0c\u5b83\u662f\u4e0d\u4f1a\u5360\u7528\u5185\u5b58\u7a7a\u95f4\u7684\u3002\u4f46\u662f\u5982\u679c\u8bbe\u8ba1\u6210\u7ec4\u5408\u5173\u7cfb\uff0c\u90a3\u4e48\u7f16\u8bd1\u5668\u4f1a\u4e3a\u7a7a\u7c7b\u5206\u914d\u4e00\u4e2a\u5b57\u8282char\u7684\u5185\u5b58\u7a7a\u95f4\uff08\u6b64\u65f6\uff0c<code>sizeof(\u6d3e\u751f\u7c7b x) &gt;sizeof(\u6d3e\u751f\u7c7b\u6210\u5458\u53d8\u91cf)<\/code>\uff09\uff0c\u800c\u53c8\u7531\u4e8e\u5bf9\u9f50\u9700\u6c42\uff0c\u53ef\u80fd\u8fd9\u4e2a\u5b57\u8282\u6700\u7ec8\u751a\u81f3\u4f1a\u53d8\u6210\u4e00\u4e2aint\u5927\u5c0f\u3002<\/p>\n\n\n\n<p>\u5982\u679c\u8bbe\u8ba1\u6210private\u7ee7\u627f\u7684\u8bdd\uff0c\u53ef\u4ee5\u907f\u514d\u4e0a\u8ff0\u60c5\u51b5\u3002\u5373\uff1a<code>sizeof(\u6d3e\u751f\u7c7b x) == sizeof(\u6d3e\u751f\u7c7b\u6210\u5458\u53d8\u91cf)<\/code>\uff0c\u8fd9\u4fbf\u662f\u6240\u8c13\u7684<code>EBO<\/code>(\u7a7a\u767d\u57fa\u7c7b\u6700\u4f18\u5316)\u3002<\/p>\n\n\n\n<p><strong>\u6ce8\u610f\uff1a<\/strong><\/p>\n\n\n\n<ul><li>\u4e00\u4e2a\u72ec\u7acb\u5bf9\u8c61\u7684\u5927\u5c0f\u4e00\u5b9a\u4e0d\u4e3a0\uff0c\u4f46\u662f\u8fd9\u4e2a\u7ea6\u675f\u4e0d\u9002\u7528\u4e8e\u6d3e\u751f\u7c7b\u5bf9\u8c61\u5185\u7684<code>base class<\/code>\u6210\u5206\uff0c\u56e0\u4e3a\u8fd9\u90e8\u5206\u5e76\u975e\u662f\u72ec\u7acb\u7684\u3002<\/li><li>\u5728STL\u4e2d\uff0cEBO\u6280\u672f\u5e94\u7528\u5f88\u5e7f\u6cdb\u3002\u5176<code>base class<\/code>\u5f80\u5f80\u662f\u542b\u6709<code>typedefs<\/code>&nbsp;\u7684\u57fa\u7c7b\u3002\u4f8b\u5982\uff1a<code>base classes 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[&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/posts\/3803"}],"collection":[{"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3803"}],"version-history":[{"count":1,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/posts\/3803\/revisions"}],"predecessor-version":[{"id":3804,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=\/wp\/v2\/posts\/3803\/revisions\/3804"}],"wp:attachment":[{"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3803"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3803"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.coolcoding.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3803"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}