{"id":74435,"date":"2024-02-27T10:40:42","date_gmt":"2024-02-27T02:40:42","guid":{"rendered":"https:\/\/docs.pingcode.com\/?p=74435"},"modified":"2024-02-27T10:40:58","modified_gmt":"2024-02-27T02:40:58","slug":"c-%e8%af%ad%e8%a8%80%e4%b8%ad%ef%bc%8cx-5-4-%e6%98%af%e4%bb%80%e4%b9%88%e6%84%8f%e6%80%9d-2","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/74435.html","title":{"rendered":"C \u8bed\u8a00\u4e2d\uff0cx += 5 == 4 \u662f\u4ec0\u4e48\u610f\u601d"},"content":{"rendered":"

\"C<\/p>\n

### C \u8bed\u8a00\u4e2d\uff0cx += 5 == 4 \u662f\u4ec0\u4e48\u610f\u601d\uff1f<\/p>\n

\u5728C\u8bed\u8a00\u4e2d\uff0c\u8868\u8fbe\u5f0f `x += 5 == 4` \u5b9e\u9645\u4e0a\u6d89\u53ca\u5230\u8fd0\u7b97\u7b26\u7684\u4f18\u5148\u7ea7\u95ee\u9898<\/strong>\u3002\u8fd9\u4e2a\u8868\u8fbe\u5f0f\u53ef\u4ee5\u5206\u89e3\u4e3a `x += (5 == 4)`\uff0c\u610f\u5473\u7740\u9996\u5148\u6267\u884c\u6bd4\u8f83\u8fd0\u7b97 `5 == 4`\uff0c\u7136\u540e\u5c06\u6bd4\u8f83\u7684\u7ed3\u679c\uff08`false`\uff0c\u5728C\u8bed\u8a00\u4e2d\u4ee50\u8868\u793a\uff09\u52a0\u5230 `x` \u4e0a\u3002\u56e0\u6b64\uff0c\u8fd9\u4e2a\u8868\u8fbe\u5f0f\u7684\u6838\u5fc3\u662f\u7406\u89e3C\u8bed\u8a00\u4e2d\u7684\u8fd0\u7b97\u7b26\u4f18\u5148\u7ea7\u4ee5\u53ca\u5982\u4f55\u5c06\u6bd4\u8f83\u8fd0\u7b97\u7684\u7ed3\u679c\u5e94\u7528\u4e8e\u8d4b\u503c\u8fd0\u7b97<\/strong>\u3002<\/p>\n

\u5728\u8fd9\u91cc\uff0c\u6211\u4eec\u91cd\u70b9\u5c55\u5f00\u8ba8\u8bba\u8fd0\u7b97\u7b26\u4f18\u5148\u7ea7<\/strong>\u3002C\u8bed\u8a00\u4e2d\u7684\u8fd0\u7b97\u7b26\u4f18\u5148\u7ea7\u51b3\u5b9a\u4e86\u590d\u6742\u8868\u8fbe\u5f0f\u4e2d\u5404\u4e2a\u90e8\u5206\u7684\u8ba1\u7b97\u987a\u5e8f\u3002\u5728\u4e0a\u8ff0\u8868\u8fbe\u5f0f\u4e2d\uff0c\u6bd4\u8f83\u8fd0\u7b97\u7b26 `==` \u7684\u4f18\u5148\u7ea7\u9ad8\u4e8e\u8d4b\u503c\u8fd0\u7b97\u7b26 `+=`\u3002\u56e0\u6b64\uff0c`5 == 4` \u9996\u5148\u88ab\u8bc4\u4f30\uff0c\u7ed3\u679c\u4e3a `false`\uff08\u6216\u8005\u8bf4\uff0c\u4ee5\u6574\u65700\u8868\u793a\uff09\u3002\u4e4b\u540e\uff0c\u8fd9\u4e2a\u7ed3\u679c\uff08\u53730\uff09\u88ab\u52a0\u5230 `x` \u7684\u5f53\u524d\u503c\u4e0a\u3002\u5982\u679c `x` \u7684\u521d\u59cb\u503c\u4e3a10\uff0c\u6267\u884c\u8fd9\u4e2a\u8868\u8fbe\u5f0f\u540e\uff0c`x` \u7684\u503c\u5c06\u4fdd\u6301\u4e0d\u53d8\uff0c\u56e0\u4e3a\u5b83\u5b9e\u9645\u4e0a\u662f\u4e0e0\u8fdb\u884c\u4e86\u52a0\u6cd5\u64cd\u4f5c\u3002<\/p>\n

—<\/p>\n

### \u4e00\u3001\u8fd0\u7b97\u7b26\u4f18\u5148\u7ea7\u548c\u8868\u8fbe\u5f0f\u6c42\u503c<\/p>\n

\u5728C\u8bed\u8a00\u7f16\u7a0b\u4e2d\uff0c\u7406\u89e3\u8fd0\u7b97\u7b26\u4f18\u5148\u7ea7<\/strong>\u5bf9\u4e8e\u6b63\u786e\u89e3\u8bfb\u548c\u7f16\u5199\u4ee3\u7801\u81f3\u5173\u91cd\u8981\u3002\u8fd0\u7b97\u7b26\u4f18\u5148\u7ea7\u51b3\u5b9a\u4e86\u5f53\u4e00\u4e2a\u8868\u8fbe\u5f0f\u4e2d\u6709\u591a\u4e2a\u8fd0\u7b97\u7b26\u65f6\uff0c\u54ea\u4e2a\u8fd0\u7b97\u7b26\u4f1a\u5148\u88ab\u6267\u884c\u3002C\u8bed\u8a00\u6807\u51c6\u5b9a\u4e49\u4e86\u4e00\u4e2a\u8fd0\u7b97\u7b26\u4f18\u5148\u7ea7\u7684\u6e05\u6670\u987a\u5e8f\uff0c\u8fd9\u6709\u52a9\u4e8e\u907f\u514d\u7f16\u5199\u4ee3\u7801\u65f6\u7684\u6df7\u6dc6\u3002<\/p>\n

\u6bd4\u8f83\u8fd0\u7b97\u7b26<\/strong>\uff08\u5982 `==`\uff09\u901a\u5e38\u9ad8\u4e8e\u8d4b\u503c\u8fd0\u7b97\u7b26<\/strong>\uff08\u5982 `+=`\u3001`=`\uff09\u3002\u8fd9\u610f\u5473\u7740\u5728\u6267\u884c\u7c7b\u4f3c `x += 5 == 4` \u7684\u8868\u8fbe\u5f0f\u65f6\uff0c\u4f1a\u5148\u8bc4\u4f30 `5 == 4`\u3002\u8fd9\u4e00\u8bc4\u4f30\u6b65\u9aa4\u662f\u5224\u65ad5\u662f\u5426\u7b49\u4e8e4\uff0c\u663e\u7136\u7ed3\u679c\u4e3a `false`\uff0c\u5728C\u8bed\u8a00\u4e2d\u75280\u6765\u8868\u793a\u3002\u63a5\u4e0b\u6765\uff0c\u8fd9\u4e2a\u7ed3\u679c\uff080\uff09\u4f1a\u88ab\u7528\u5728\u8d4b\u503c\u64cd\u4f5c\u4e2d\u3002<\/p>\n

#### \u6df1\u5165\u7406\u89e3\u8868\u8fbe\u5f0f\u6c42\u503c<\/p>\n

\u8868\u8fbe\u5f0f\u6c42\u503c\u4e0d\u4ec5\u4ec5\u662f\u7406\u89e3\u54ea\u4e2a\u8fd0\u7b97\u7b26\u4f1a\u5148\u88ab\u6267\u884c\u90a3\u4e48\u7b80\u5355\u3002\u5b83\u8fd8\u6d89\u53ca\u5230\u5982\u4f55\u5c06\u5404\u4e2a\u8fd0\u7b97\u7684\u7ed3\u679c\u9010\u6b65\u5e94\u7528\u5230\u6574\u4e2a\u8868\u8fbe\u5f0f\u4e2d\u3002\u5728 `x += 5 == 4` \u7684\u4f8b\u5b50\u4e2d\uff0c`5 == 4` \u7684\u7ed3\u679c\u662f0\uff0c\u7136\u540e\u8fd9\u4e2a\u7ed3\u679c\u88ab\u52a0\u5230 `x` \u7684\u503c\u4e0a\u3002<\/p>\n

### \u4e8c\u3001C\u8bed\u8a00\u4e2d\u7684\u6bd4\u8f83\u8fd0\u7b97\u7b26<\/p>\n

\u5728C\u8bed\u8a00\u4e2d\uff0c\u6bd4\u8f83\u8fd0\u7b97\u7b26<\/strong>\u7528\u4e8e\u6bd4\u8f83\u4e24\u4e2a\u503c\u7684\u5927\u5c0f\u6216\u76f8\u7b49\u6027\u3002\u8fd9\u4e9b\u8fd0\u7b97\u7b26\u5305\u62ec\u7b49\u4e8e (`==`)\u3001\u4e0d\u7b49\u4e8e (`!=`)\u3001\u5927\u4e8e (`>`)\u3001\u5c0f\u4e8e (`<`)\u3001\u5927\u4e8e\u7b49\u4e8e (`>=`)\u3001\u5c0f\u4e8e\u7b49\u4e8e (`<=`) \u7b49\u3002<\/p>\n

\u7b49\u4e8e\u8fd0\u7b97\u7b26<\/strong> (`==`) \u662f\u7528\u6765\u5224\u65ad\u4e24\u4e2a\u8868\u8fbe\u5f0f\u7684\u503c\u662f\u5426\u76f8\u7b49\u3002\u5982\u679c\u76f8\u7b49\uff0c\u8868\u8fbe\u5f0f\u7684\u7ed3\u679c\u4e3a\u771f\uff081\uff09\uff0c\u5426\u5219\u4e3a\u5047\uff080\uff09\u3002\u5728\u5b9e\u9645\u7f16\u7a0b\u4e2d\uff0c\u7b49\u4e8e\u8fd0\u7b97\u7b26\u7ecf\u5e38\u7528\u4e8e\u6761\u4ef6\u5224\u65ad\u4e2d\uff0c\u5982if\u8bed\u53e5\u6216while\u5faa\u73af\u4e2d\u3002<\/p>\n

#### \u5b9e\u4f8b\u5206\u6790<\/p>\n

\u8003\u8651\u4ee5\u4e0b\u4ee3\u7801\u6bb5\uff1a<\/p>\n

“`c<\/p>\n

int x = 10;<\/p>\n

x += 5 == 4;<\/p>\n

“`<\/p>\n

\u8fd9\u91cc\uff0c`5 == 4` \u7684\u7ed3\u679c\u4e3a0\uff0c\u56e0\u4e3a5\u4e0d\u7b49\u4e8e4\u3002\u7136\u540e\uff0c0\u88ab\u52a0\u5230 `x` \u7684\u503c\u4e0a\uff0c\u6700\u7ec8 `x` \u7684\u503c\u4ecd\u7136\u662f10\u3002<\/p>\n

### \u4e09\u3001C\u8bed\u8a00\u4e2d\u7684\u8d4b\u503c\u8fd0\u7b97\u7b26<\/p>\n

\u5728C\u8bed\u8a00\u4e2d<\/p>\n

\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n

\u8fd9\u4e2a\u8868\u8fbe\u5f0f\u7684\u542b\u4e49\u662f\u4ec0\u4e48\uff1f<\/strong><\/p>\n

\u8fd9\u4e2a\u8868\u8fbe\u5f0f\u5b9e\u9645\u4e0a\u662f\u4e00\u4e2a\u590d\u5408\u8d4b\u503c\u8868\u8fbe\u5f0f\uff0c\u5176\u4e2d\u7ed3\u5408\u4e86\u52a0\u6cd5\u8fd0\u7b97\u7b26\u548c\u76f8\u7b49\u8fd0\u7b97\u7b26\u3002\u8868\u8fbe\u5f0f\u4e2d\u7684 x += 5 \u5b9e\u9645\u4e0a\u7b49\u4ef7\u4e8e x = x + 5\u3002\u800c\u7136\u540e\u518d\u6bd4\u8f83 x + 5 \u7684\u7ed3\u679c\u662f\u5426\u7b49\u4e8e 4\u3002\u5982\u679c x + 5 \u7684\u7ed3\u679c\u7b49\u4e8e 4\uff0c\u90a3\u4e48\u6574\u4e2a\u8868\u8fbe\u5f0f\u7684\u503c\u4f1a\u662f\u771f\uff08true\uff09\uff0c\u5426\u5219\u4e3a\u5047\uff08false\uff09\u3002<\/p>\n

\u8fd9\u4e2a\u8868\u8fbe\u5f0f\u5728 C \u8bed\u8a00\u4e2d\u7684\u8fd0\u884c\u987a\u5e8f\u662f\u600e\u6837\u7684\uff1f<\/strong><\/p>\n

\u5728 C \u8bed\u8a00\u4e2d\uff0c\u590d\u5408\u8d4b\u503c\u8fd0\u7b97\u7b26\u7684\u8fd0\u884c\u987a\u5e8f\u662f\u4ece\u53f3\u5411\u5de6\u7684\u3002\u4e5f\u5c31\u662f\u8bf4\uff0c\u9996\u5148\u8ba1\u7b97\u7b49\u53f7\u53f3\u4fa7\u7684\u8868\u8fbe\u5f0f x + 5 == 4\uff0c\u7136\u540e\u5c06\u7ed3\u679c\u8d4b\u503c\u7ed9 x\uff0c\u5373 x \u7684\u503c\u5c06\u6839\u636e\u7b49\u53f7\u53f3\u4fa7\u8868\u8fbe\u5f0f\u8ba1\u7b97\u7684\u7ed3\u679c\u8fdb\u884c\u66f4\u65b0\u3002<\/p>\n

\u5982\u4f55\u6b63\u786e\u7406\u89e3\u8fd9\u4e2a\u8868\u8fbe\u5f0f\uff1f<\/strong><\/p>\n

\u8981\u6b63\u786e\u7406\u89e3\u8fd9\u4e2a\u8868\u8fbe\u5f0f\uff0c\u9996\u5148\u5e94\u8be5\u660e\u767d C \u8bed\u8a00\u4e2d\u7684\u8fd0\u7b97\u987a\u5e8f\u89c4\u5219\uff0c\u7406\u89e3\u590d\u5408\u8d4b\u503c\u8fd0\u7b97\u7b26\u7684\u529f\u80fd\uff0c\u4ee5\u53ca\u76f8\u7b49\u8fd0\u7b97\u7b26\u7684\u6bd4\u8f83\u64cd\u4f5c\u3002\u901a\u8fc7\u9010\u6b65\u62c6\u89e3\u8868\u8fbe\u5f0f\u5e76\u660e\u786e\u6bcf\u4e2a\u6b65\u9aa4\u7684\u8fd0\u884c\u987a\u5e8f\uff0c\u53ef\u4ee5\u66f4\u6e05\u695a\u5730\u7406\u89e3\u8fd9\u4e2a\u8868\u8fbe\u5f0f\u7684\u542b\u4e49\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"### C \u8bed\u8a00\u4e2d\uff0cx += 5 == 4 \u662f\u4ec0\u4e48\u610f\u601d\uff1f \u5728C\u8bed\u8a00\u4e2d\uff0c\u8868\u8fbe\u5f0f `x += 5 == 4` \u5b9e\u9645 […]","protected":false},"author":1,"featured_media":74438,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/74435"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=74435"}],"version-history":[{"count":0,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/74435\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/74438"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=74435"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=74435"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=74435"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}