{"id":74795,"date":"2024-02-27T14:43:16","date_gmt":"2024-02-27T06:43:16","guid":{"rendered":"https:\/\/docs.pingcode.com\/?p=74795"},"modified":"2024-02-27T14:43:30","modified_gmt":"2024-02-27T06:43:30","slug":"c%e8%af%ad%e8%a8%80%e4%b8%ad%e7%9a%84%e8%81%94%e5%90%88%e4%bd%93%e4%bd%bf%e7%94%a8%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/74795.html","title":{"rendered":"C\u8bed\u8a00\u4e2d\u7684\u8054\u5408\u4f53\u4f7f\u7528\u65b9\u6cd5"},"content":{"rendered":"<p style=\"text-align:center;\" ><img fetchpriority=\"high\" decoding=\"async\" class=\"alignnone size-full wp-image-74796\" src=\"https:\/\/cdn-docs.pingcode.com\/wp-content\/uploads\/2024\/02\/img-O4ceEkAmD14JhSivXHrB2Ih4.png?x-oss-process=image\/auto-orient,1\/format,webp\" width=\"600\" height=\"342\" alt=\"C\u8bed\u8a00\u4e2d\u7684\u8054\u5408\u4f53\u4f7f\u7528\u65b9\u6cd5\" 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member2;&#8230;.}\uff0c\u5176\u4e2dTag\u662f\u8054\u5408\u4f53\u6807\u7b7e\uff0c\u53ef\u4e3a\u8054\u5408\u4f53\u5b9e\u4f8b\u5316\u63d0\u4f9b\u540d\u79f0\u3002\u58f0\u660e\u8054\u5408\u4f53\u53d8\u91cf\u7684\u65b9\u6cd5\u5305\u62ec\u76f4\u63a5\u3001\u901a\u8fc7\u6807\u7b7e\u548c\u901a\u8fc7\u7c7b\u578b\u7684\u65b9\u5f0f\u3002\u800c\u8bbf\u95ee\u8054\u5408\u4f53\u6210\u5458\uff0c\u53ea\u9700\u8981\u4f7f\u7528\u70b9\u53f7(.)\u6216\u8005\u6307\u9488\u8fd0\u7b97\u7b26(->)\u8ddf\u5728\u8054\u5408\u4f53\u53d8\u91cf\u540d\u6216\u8005\u8054\u5408\u4f53\u6307\u9488\u540e\u9762\u5373\u53ef\u3002<\/p>\n<h2><strong>\u4e00\u3001\u5b9a\u4e49\u8054\u5408\u4f53<\/strong><\/h2>\n<p>\u5728C\u8bed\u8a00\u4e2d\uff0c\u5b9a\u4e49\u8054\u5408\u4f53\u7684\u8bed\u6cd5\u4e3a\uff1aunion UnionName {dataType member1; dataType member2; &#8230; }\u3002\u8054\u5408\u4f53\u5185\u7684\u6210\u5458\u4f1a\u5171\u4eab\u540c\u4e00\u5757\u5185\u5b58\u7a7a\u95f4\uff0c\u8fd9\u4e2a\u7a7a\u95f4\u7684\u5927\u5c0f\u7b49\u4e8e\u6700\u5927\u6210\u5458\u6240\u9700\u7684\u7a7a\u95f4\u3002\u8fd9\u4e5f\u5c31\u610f\u5473\u7740\uff0c\u5728\u540c\u4e00\u65f6\u95f4\uff0c\u53ea\u80fd\u6709\u4e00\u4e2a\u6210\u5458\u5f97\u5230\u4f7f\u7528\u3002\u5b9a\u4e49\u7684\u8054\u5408\u4f53\u53ef\u4ee5\u88ab\u91cd\u590d\u4f7f\u7528\u3002<\/p>\n<p>\u4f8b\u5982\uff0c\u5982\u679c\u6211\u4eec\u8981\u5b9a\u4e49\u4e00\u4e2a\u53ef\u4ee5\u5b58\u50a8\u6574\u6570\uff0c\u6d6e\u70b9\u6570\u548c\u5b57\u7b26\u7684\u8054\u5408\u4f53\uff0c\u53ef\u4ee5\u8fd9\u6837\u5b9a\u4e49\uff1a<\/p>\n<p>union Data<\/p>\n<p>{<\/p>\n<p>    int i;<\/p>\n<p>    float f;<\/p>\n<p>    char str[20];<\/p>\n<p>};<\/p>\n<h2><strong>\u4e8c\u3001\u58f0\u660e\u8054\u5408\u4f53\u53d8\u91cf<\/strong><\/h2>\n<p>\u8054\u5408\u4f53\u53d8\u91cf\u7684\u58f0\u660e\u7c7b\u4f3c\u4e8e\u7ed3\u6784\u4f53\u7684\u58f0\u660e\u3002\u53ef\u4ee5\u5728\u5b9a\u4e49\u8054\u5408\u4f53\u65f6\u58f0\u660e\uff0c\u4e5f\u53ef\u4ee5\u901a\u8fc7\u8054\u5408\u4f53\u540d\u540e\u58f0\u660e\uff0c\u4e5f\u53ef\u4ee5\u901a\u8fc7\u8054\u5408\u4f53\u7c7b\u578b\u58f0\u660e\u3002<\/p>\n<p>\u4f8b\u5982\uff1a<\/p>\n<p>union Data data1; \/\/ \u901a\u8fc7\u8054\u5408\u4f53\u540d\u58f0\u660e<\/p>\n<p>union Data data2 = {10}; \/\/ \u5728\u5b9a\u4e49\u8054\u5408\u4f53\u7684\u540c\u65f6\u8fdb\u884c\u58f0\u660e\u5e76\u521d\u59cb\u5316\uff0c\u6b64\u65f6\u6574\u5f62\u6210\u5458i\u88ab\u521d\u59cb\u5316\u4e3a10<\/p>\n<h2><strong>\u4e09\u3001\u8bbf\u95ee\u8054\u5408\u4f53\u6210\u5458<\/strong><\/h2>\n<p>\u8bbf\u95ee\u8054\u5408\u4f53\u6210\u5458\u53ef\u4ee5\u901a\u8fc7\u70b9\u8fd0\u7b97\u7b26(.)\u548c\u7bad\u5934\u8fd0\u7b97\u7b26(->)\u8fdb\u884c\u8bbf\u95ee\u3002\u70b9\u8fd0\u7b97\u7b26\u7528\u4e8e\u8bbf\u95ee\u8054\u5408\u4f53\u53d8\u91cf\u7684\u6210\u5458\uff0c\u7bad\u5934\u8fd0\u7b97\u7b26\u7528\u4e8e\u8bbf\u95ee\u8054\u5408\u4f53\u6307\u9488\u6240\u6307\u5411\u7684\u6210\u5458\u3002<\/p>\n<p>\u4f8b\u5982\uff1a<\/p>\n<p>union Data data1;<\/p>\n<p>data1.i = 10; \/\/ \u901a\u8fc7\u70b9\u8fd0\u7b97\u7b26\u8bbf\u95ee\u6574\u5f62\u6210\u5458<\/p>\n<p>union Data *ptr;<\/p>\n<p>ptr = &data1;<\/p>\n<p>ptr->f = 20.0; \/\/ 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