{"id":3250,"date":"2025-03-27T23:57:43","date_gmt":"2025-03-27T15:57:43","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=3250"},"modified":"2025-03-27T23:57:43","modified_gmt":"2025-03-27T15:57:43","slug":"c-%e5%ad%98%e5%82%a8%e7%b1%bb%ef%bc%88storage-classes-in-c%ef%bc%89","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2025\/03\/27\/c-%e5%ad%98%e5%82%a8%e7%b1%bb%ef%bc%88storage-classes-in-c%ef%bc%89\/","title":{"rendered":"C++ \u5b58\u50a8\u7c7b\uff08Storage Classes in C++\uff09"},"content":{"rendered":"\n

\u5728 C++ \u4e2d\uff0c\u5b58\u50a8\u7c7b\u5b9a\u4e49\u4e86\u53d8\u91cf\u6216\u51fd\u6570\u7684\u751f\u547d\u5468\u671f\u3001\u4f5c\u7528\u57df\u4ee5\u53ca\u5b83\u4eec\u7684\u5b58\u50a8\u4f4d\u7f6e\u3002\u5b58\u50a8\u7c7b\u51b3\u5b9a\u4e86\u53d8\u91cf\u7684\u5b58\u50a8\u65b9\u5f0f\u548c\u751f\u5b58\u5468\u671f\uff0c\u5e76\u6307\u5b9a\u5b83\u4eec\u662f\u5426\u4e3a\u5168\u5c40\u3001\u5c40\u90e8\u6216\u9759\u6001\u7684\u3002C++ \u63d0\u4f9b\u4e86\u51e0\u79cd\u5b58\u50a8\u7c7b\u4fee\u9970\u7b26\uff0c\u5305\u62ec auto<\/code>\u3001register<\/code>\u3001static<\/code>\u3001extern<\/code> \u548c mutable<\/code> \u7b49\u3002\u6bcf\u4e2a\u5b58\u50a8\u7c7b\u6709\u5176\u72ec\u7279\u7684\u529f\u80fd\u548c\u7528\u9014\u3002<\/p>\n\n\n\n

\n\n\n\n

1. auto<\/code> \u5b58\u50a8\u7c7b<\/strong><\/h2>\n\n\n\n

auto<\/code> \u662f C++ \u4e2d\u6700\u57fa\u672c\u7684\u5b58\u50a8\u7c7b\u4fee\u9970\u7b26\u3002\u5728 C++11 \u4e4b\u524d\uff0cauto<\/code> \u7528\u4e8e\u81ea\u52a8\u63a8\u5bfc\u53d8\u91cf\u7684\u7c7b\u578b\u3002\u7136\u800c\uff0c\u5728\u73b0\u4ee3 C++\uff08C++11 \u4ee5\u540e\uff09\uff0cauto<\/code> \u4e3b\u8981\u7528\u4e8e\u7c7b\u578b\u63a8\u5bfc\uff0c\u58f0\u660e\u65f6\u4e0d\u9700\u8981\u660e\u786e\u6307\u5b9a\u7c7b\u578b\u3002<\/p>\n\n\n\n

1.1 \u793a\u4f8b\uff1a\u4f7f\u7528 auto<\/code> \u5b58\u50a8\u7c7b<\/strong><\/h3>\n\n\n\n
#include <iostream>\nusing namespace std;\n\nint main() {\n    auto x = 10;   \/\/ auto \u63a8\u5bfc x \u4e3a int \u7c7b\u578b\n    auto y = 3.14; \/\/ auto \u63a8\u5bfc y \u4e3a double \u7c7b\u578b\n    cout << \"x: \" << x << \", y: \" << y << endl;\n    return 0;\n}<\/code><\/pre>\n\n\n\n
\u8f93\u51fa\uff1a<\/strong><\/p>\n\n\n\n
x: 10, y: 3.14<\/code><\/pre>\n\n\n\n
    \n
  • auto<\/code> \u81ea\u52a8\u63a8\u5bfc\u53d8\u91cf x<\/code> \u548c y<\/code> \u7684\u7c7b\u578b\u3002<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n
    2. register<\/code> \u5b58\u50a8\u7c7b<\/strong><\/h2>\n\n\n\n
    register<\/code> \u5b58\u50a8\u7c7b\u7528\u4e8e\u544a\u8bc9\u7f16\u8bd1\u5668\u8be5\u53d8\u91cf\u5e94\u8be5\u5c3d\u53ef\u80fd\u5b58\u50a8\u5728 CPU \u7684\u5bc4\u5b58\u5668\u4e2d\uff0c\u4ee5\u63d0\u9ad8\u8bbf\u95ee\u901f\u5ea6\u3002\u73b0\u4ee3\u7f16\u8bd1\u5668\u901a\u5e38\u4f1a\u81ea\u52a8\u4f18\u5316\u53d8\u91cf\u5b58\u50a8\u4f4d\u7f6e\uff0cregister<\/code> \u7684\u4f7f\u7528\u53d8\u5f97\u4e0d\u90a3\u4e48\u5e38\u89c1\u3002<\/p>\n\n\n\n
    2.1 \u793a\u4f8b\uff1a\u4f7f\u7528 register<\/code> \u5b58\u50a8\u7c7b<\/strong><\/h3>\n\n\n\n
    #include <iostream>\nusing namespace std;\n\nint main() {\n    register int count = 100;  \/\/ \u5c1d\u8bd5\u5c06 count \u5b58\u50a8\u5728\u5bc4\u5b58\u5668\u4e2d\n    cout << \"Count: \" << count << endl;\n    return 0;\n}<\/code><\/pre>\n\n\n\n
    \u8bf4\u660e\uff1a<\/strong><\/p>\n\n\n\n
      \n
    • register<\/code> \u4fee\u9970\u7b26\u8bd5\u56fe\u5c06\u53d8\u91cf count<\/code> \u5b58\u50a8\u5728\u5bc4\u5b58\u5668\u4e2d\uff0c\u53ef\u80fd\u63d0\u9ad8\u8bbf\u95ee\u901f\u5ea6\u3002<\/li>\n\n\n\n
    • register<\/code> \u4e0d\u80fd\u7528\u4e8e\u58f0\u660e\u53d6\u5730\u5740\u7684\u53d8\u91cf\uff08\u4f8b\u5982\u4e0d\u80fd\u5bf9 register<\/code> \u53d8\u91cf\u4f7f\u7528 &count<\/code>\uff09\u3002<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n
      3. static<\/code> \u5b58\u50a8\u7c7b<\/strong><\/h2>\n\n\n\n
      static<\/code> \u5b58\u50a8\u7c7b\u4fee\u9970\u7b26\u7528\u4e8e\u63a7\u5236\u53d8\u91cf\u7684\u751f\u547d\u5468\u671f\u548c\u4f5c\u7528\u57df\u3002\u4f7f\u7528 static<\/code> \u4fee\u9970\u7684\u5c40\u90e8\u53d8\u91cf\u4e0d\u4f1a\u5728\u51fd\u6570\u8c03\u7528\u7ed3\u675f\u65f6\u9500\u6bc1\uff0c\u5b83\u4eec\u7684\u503c\u5c06\u5728\u591a\u4e2a\u51fd\u6570\u8c03\u7528\u4e4b\u95f4\u4fdd\u6301\u4e0d\u53d8\u3002\u5bf9\u4e8e\u5168\u5c40\u53d8\u91cf\uff0cstatic<\/code> \u9650\u5236\u4e86\u5b83\u4eec\u7684\u4f5c\u7528\u57df\uff0c\u4ec5\u5728\u5f53\u524d\u6587\u4ef6\u4e2d\u53ef\u89c1\uff0c\u65e0\u6cd5\u88ab\u5916\u90e8\u6587\u4ef6\u8bbf\u95ee\u3002<\/p>\n\n\n\n
      3.1 \u793a\u4f8b\uff1a\u5c40\u90e8\u53d8\u91cf\u4e2d\u7684 static<\/code><\/strong><\/h3>\n\n\n\n
      #include <iostream>\nusing namespace std;\n\nvoid increment() {\n    static int count = 0; \/\/ \u9759\u6001\u5c40\u90e8\u53d8\u91cf\n    count++;\n    cout << \"Count: \" << count << endl;\n}\n\nint main() {\n    increment(); \/\/ \u8c03\u7528\u4e00\u6b21\n    increment(); \/\/ \u8c03\u7528\u4e24\u6b21\n    increment(); \/\/ \u8c03\u7528\u4e09\u6b21\n    return 0;\n}<\/code><\/pre>\n\n\n\n
      \u8f93\u51fa\uff1a<\/strong><\/p>\n\n\n\n
      Count: 1\nCount: 2\nCount: 3<\/code><\/pre>\n\n\n\n
        \n
      • static<\/code> \u4fee\u9970\u7b26\u4f7f\u5f97 count<\/code> \u5728\u591a\u6b21\u8c03\u7528 increment()<\/code> \u51fd\u6570\u65f6\u4fdd\u6301\u5176\u503c\uff0c\u800c\u4e0d\u662f\u6bcf\u6b21\u8c03\u7528\u65f6\u91cd\u65b0\u521d\u59cb\u5316\u3002<\/li>\n<\/ul>\n\n\n\n
        3.2 \u793a\u4f8b\uff1a\u5168\u5c40\u53d8\u91cf\u4e2d\u7684 static<\/code><\/strong><\/h3>\n\n\n\n
        #include <iostream>\nusing namespace std;\n\nstatic int globalVar = 100;  \/\/ \u5168\u5c40\u9759\u6001\u53d8\u91cf\n\nint main() {\n    cout << \"GlobalVar: \" << globalVar << endl;\n    return 0;\n}<\/code><\/pre>\n\n\n\n
        \u8bf4\u660e\uff1a<\/strong><\/p>\n\n\n\n
          \n
        • globalVar<\/code> \u88ab\u4fee\u9970\u4e3a static<\/code>\uff0c\u56e0\u6b64\u5b83\u4ec5\u5bf9\u5f53\u524d\u6587\u4ef6\u53ef\u89c1\uff0c\u4e0d\u80fd\u88ab\u5176\u4ed6\u6587\u4ef6\u8bbf\u95ee\u3002<\/li>\n<\/ul>\n\n\n\n
          \n\n\n\n
          4. extern<\/code> \u5b58\u50a8\u7c7b<\/strong><\/h2>\n\n\n\n
          extern<\/code> \u5b58\u50a8\u7c7b\u7528\u4e8e\u58f0\u660e\u53d8\u91cf\u6216\u51fd\u6570\u662f\u5b9a\u4e49\u5728\u5176\u4ed6\u6587\u4ef6\u6216\u5176\u4ed6\u5730\u65b9\u7684\u3002\u5b83\u901a\u5e38\u7528\u4e8e\u5728\u591a\u4e2a\u6e90\u6587\u4ef6\u4e4b\u95f4\u5171\u4eab\u53d8\u91cf\u6216\u51fd\u6570\u3002<\/p>\n\n\n\n
          4.1 \u793a\u4f8b\uff1a\u4f7f\u7528 extern<\/code> \u5b58\u50a8\u7c7b<\/strong><\/h3>\n\n\n\n
          \/\/ file1.cpp\n#include <iostream>\nusing namespace std;\n\nextern int count;  \/\/ \u58f0\u660e\u4e00\u4e2a\u5916\u90e8\u53d8\u91cf\n\nint main() {\n    count = 10;  \/\/ \u8bbe\u7f6e count \u7684\u503c\n    cout << \"Count: \" << count << endl;\n    return 0;\n}<\/code><\/pre>\n\n\n\n
          \/\/ file2.cpp\nint count = 0;  \/\/ \u5b9a\u4e49\u53d8\u91cf count<\/code><\/pre>\n\n\n\n
          \u8bf4\u660e\uff1a<\/strong><\/p>\n\n\n\n
            \n
          • extern<\/code> \u58f0\u660e count<\/code> \u53d8\u91cf\uff0c\u544a\u8bc9\u7f16\u8bd1\u5668\u8be5\u53d8\u91cf\u5728\u5176\u4ed6\u5730\u65b9\uff08\u5982 file2.cpp<\/code>\uff09\u5b9a\u4e49\u3002<\/li>\n\n\n\n
          • count<\/code> \u5728 file2.cpp<\/code> \u4e2d\u5b9a\u4e49\uff0c\u56e0\u6b64\u5728 file1.cpp<\/code> \u4e2d\u53ef\u4ee5\u4f7f\u7528\u3002<\/li>\n<\/ul>\n\n\n\n
            \n\n\n\n
            5. mutable<\/code> \u5b58\u50a8\u7c7b<\/strong><\/h2>\n\n\n\n
            mutable<\/code> \u5b58\u50a8\u7c7b\u4ec5\u9002\u7528\u4e8e\u7c7b\u7684\u6210\u5458\u53d8\u91cf\uff0c\u8868\u793a\u5373\u4f7f\u5728 const<\/code> \u6210\u5458\u51fd\u6570\u4e2d\uff0cmutable<\/code> \u4fee\u9970\u7684\u6210\u5458\u53d8\u91cf\u4e5f\u53ef\u4ee5\u88ab\u4fee\u6539\u3002mutable<\/code> \u4fee\u9970\u7b26\u901a\u5e38\u7528\u4e8e\u5e0c\u671b\u5728 const<\/code> \u6210\u5458\u51fd\u6570\u4e2d\u4fee\u6539\u67d0\u4e9b\u6210\u5458\u7684\u573a\u666f\u3002<\/p>\n\n\n\n
            5.1 \u793a\u4f8b\uff1a\u4f7f\u7528 mutable<\/code> \u4fee\u9970\u7b26<\/strong><\/h3>\n\n\n\n
            #include <iostream>\nusing namespace std;\n\nclass MyClass {\npublic:\n    mutable int counter = 0;\n\n    void increment() const {  \/\/ const \u6210\u5458\u51fd\u6570\n        counter++;  \/\/ \u53ef\u4ee5\u4fee\u6539 mutable \u6210\u5458\n    }\n\n    int getCounter() const {\n        return counter;\n    }\n};\n\nint main() {\n    MyClass obj;\n    obj.increment();\n    cout << \"Counter: \" << obj.getCounter() << endl;  \/\/ \u8f93\u51fa 1\n    return 0;\n}<\/code><\/pre>\n\n\n\n
            \u8f93\u51fa\uff1a<\/strong><\/p>\n\n\n\n
            Counter: 1<\/code><\/pre>\n\n\n\n
              \n
            • \u5373\u4f7f increment()<\/code> \u662f const<\/code> \u6210\u5458\u51fd\u6570\uff0c\u4f46\u7531\u4e8e counter<\/code> \u88ab\u58f0\u660e\u4e3a mutable<\/code>\uff0c\u5b83\u4ecd\u7136\u53ef\u4ee5\u5728 const<\/code> \u6210\u5458\u51fd\u6570\u4e2d\u4fee\u6539\u3002<\/li>\n<\/ul>\n\n\n\n
              \n\n\n\n
              6. \u603b\u7ed3<\/strong><\/h2>\n\n\n\n
              C++ \u63d0\u4f9b\u4e86\u51e0\u79cd\u5b58\u50a8\u7c7b\u4fee\u9970\u7b26\uff0c\u7528\u4e8e\u5b9a\u4e49\u53d8\u91cf\u7684\u5b58\u50a8\u65b9\u5f0f\u3001\u4f5c\u7528\u57df\u548c\u751f\u547d\u5468\u671f\u3002\u5e38\u89c1\u7684\u5b58\u50a8\u7c7b\u4fee\u9970\u7b26\u5305\u62ec\uff1a<\/p>\n\n\n\n
              \u5b58\u50a8\u7c7b<\/th>\u8bf4\u660e<\/th>\u793a\u4f8b<\/th><\/tr><\/thead>
              auto<\/code><\/td>\u81ea\u52a8\u63a8\u5bfc\u53d8\u91cf\u7c7b\u578b\uff0c\u73b0\u4ee3 C++ \u4f7f\u7528\u7c7b\u578b\u63a8\u5bfc<\/td>auto x = 10;<\/code><\/td><\/tr>
              register<\/code><\/td>\u5c1d\u8bd5\u5c06\u53d8\u91cf\u5b58\u50a8\u5728 CPU \u5bc4\u5b58\u5668\u4e2d\uff0c\u63d0\u9ad8\u8bbf\u95ee\u901f\u5ea6<\/td>register int count;<\/code><\/td><\/tr>
              static<\/code><\/td>\u5c40\u90e8\u53d8\u91cf\u7684\u751f\u547d\u5468\u671f\u5ef6\u7eed\uff0c\u6216\u5168\u5c40\u53d8\u91cf\u7684\u4f5c\u7528\u57df\u9650\u5236\u5728\u5f53\u524d\u6587\u4ef6\u5185<\/td>static int count = 0;<\/code><\/td><\/tr>
              extern<\/code><\/td>\u58f0\u660e\u53d8\u91cf\u6216\u51fd\u6570\u5728\u5176\u4ed6\u6587\u4ef6\u4e2d\u5b9a\u4e49<\/td>extern int count;<\/code><\/td><\/tr>
              mutable<\/code><\/td>\u5141\u8bb8\u5728 const<\/code> \u6210\u5458\u51fd\u6570\u4e2d\u4fee\u6539\u53d8\u91cf\u7684\u503c<\/td>mutable int counter;<\/code><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
              \u5408\u7406\u4f7f\u7528\u8fd9\u4e9b\u5b58\u50a8\u7c7b\u53ef\u4ee5\u6709\u6548\u5730\u63a7\u5236\u53d8\u91cf\u7684\u5b58\u50a8\u3001\u751f\u547d\u5468\u671f\u548c\u8bbf\u95ee\u6743\u9650\uff0c\u63d0\u9ad8\u7a0b\u5e8f\u7684\u6548\u7387\u548c\u53ef\u7ef4\u62a4\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
              \u5728 C++ \u4e2d\uff0c\u5b58\u50a8\u7c7b\u5b9a\u4e49\u4e86\u53d8\u91cf\u6216\u51fd\u6570\u7684\u751f\u547d\u5468\u671f\u3001\u4f5c\u7528\u57df\u4ee5\u53ca\u5b83\u4eec\u7684\u5b58\u50a8\u4f4d\u7f6e\u3002\u5b58\u50a8\u7c7b\u51b3\u5b9a\u4e86\u53d8\u91cf\u7684\u5b58\u50a8\u65b9\u5f0f\u548c\u751f\u5b58\u5468 […]<\/p>\n","protected":false},"author":1,"featured_media":3251,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[81],"tags":[],"class_list":["post-3250","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\/3250","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=3250"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3250\/revisions"}],"predecessor-version":[{"id":3252,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/3250\/revisions\/3252"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media\/3251"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=3250"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=3250"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=3250"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}