{"id":202458,"date":"2025-05-13T10:58:51","date_gmt":"2025-05-13T02:58:51","guid":{"rendered":"https:\/\/server.hk\/cnblog\/202458\/"},"modified":"2025-05-13T10:58:51","modified_gmt":"2025-05-13T02:58:51","slug":"%e4%b8%ba%e4%bb%80%e4%b9%88%e6%88%91%e5%9c%a8-php-%e4%b8%ad%e4%bd%bf%e7%94%a8-empty-%e8%af%ad%e8%a8%80%e7%bb%93%e6%9e%84%e8%80%8c%e4%b8%8d%e6%98%af-isset%ef%bc%8c%e4%bd%a0%e4%b9%9f%e5%ba%94","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/202458\/","title":{"rendered":"\u4e3a\u4ec0\u4e48\u6211\u5728 PHP \u4e2d\u4f7f\u7528 empty() \u8bed\u8a00\u7ed3\u6784\u800c\u4e0d\u662f isset()\uff0c\u4f60\u4e5f\u5e94\u8be5\u8fd9\u6837\u505a"},"content":{"rendered":"<p><b><\/b> <\/p>\n<h1>\u4e3a\u4ec0\u4e48\u6211\u5728 PHP \u4e2d\u4f7f\u7528 empty() \u8bed\u8a00\u7ed3\u6784\u800c\u4e0d\u662f isset()\uff0c\u4f60\u4e5f\u5e94\u8be5\u8fd9\u6837\u505a<\/h1>\n<p><span style=\"cursor: pointer\"><i><\/i>\u6536\u85cf<\/span> <\/p>\n<p>\u4f60\u5728\u5b66\u4e60<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\">\u6587\u7ae0<\/span>\u76f8\u5173\u7684\u77e5\u8bc6\u5417\uff1f\u672c\u6587<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\">\u300a\u4e3a\u4ec0\u4e48\u6211\u5728 PHP \u4e2d\u4f7f\u7528 empty() \u8bed\u8a00\u7ed3\u6784\u800c\u4e0d\u662f isset()\uff0c\u4f60\u4e5f\u5e94\u8be5\u8fd9\u6837\u505a\u300b<\/span>\uff0c\u4e3b\u8981\u4ecb\u7ecd\u7684\u5185\u5bb9\u5c31\u6d89\u53ca\u5230<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\"><\/span>\uff0c\u5982\u679c\u4f60\u60f3\u63d0\u5347\u81ea\u5df1\u7684\u5f00\u53d1\u80fd\u529b\uff0c\u5c31\u4e0d\u8981\u9519\u8fc7\u8fd9\u7bc7\u6587\u7ae0\uff0c\u5927\u5bb6\u8981\u77e5\u9053\u7f16\u7a0b\u7406\u8bba\u57fa\u7840\u548c\u5b9e\u6218\u64cd\u4f5c\u90fd\u662f\u4e0d\u53ef\u6216\u7f3a\u7684\u54e6\uff01<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.17golang.com\/uploads\/20241023\/17296902526718fa8c15083.jpg\" class=\"aligncenter\"><\/p>\n<p>\u5728 <strong>php<\/strong> \u4e2d\u8fdb\u884c\u5f00\u53d1\u65f6\uff0c\u6709\u6548\u5904\u7406\u53d8\u91cf\u68c0\u67e5\u5bf9\u4e8e\u786e\u4fdd\u5065\u58ee\u4e14\u65e0\u9519\u8bef\u7684\u4ee3\u7801\u81f3\u5173\u91cd\u8981\u3002\u4e3a\u6b64\u76ee\u7684\uff0c\u4e24\u4e2a\u5e38\u7528\u7684\u8bed\u8a00\u7ed3\u6784\u662fempty() \u548cisset()\u3002\u7136\u800c\uff0c\u5728\u8bb8\u591a\u60c5\u51b5\u4e0b\uff0c\u9009\u62e9empty()\u53ef\u80fd\u6bd4isset()\u66f4\u6709\u5229\uff0c\u4e3b\u8981\u662f\u56e0\u4e3aempty()\u51e0\u4e4e\u6db5\u76d6\u4e86isset()\u6240\u505a\u7684\u6240\u6709\u573a\u666f\u4ee5\u53ca\u989d\u5916\u7684\u68c0\u67e5\u3002\u672c\u6587\u5c06\u8bba\u8bc1\u4e3a\u4ec0\u4e48\u5728 php \u4e2d\u4e00\u81f4\u4f7f\u7528 empty() \u901a\u5e38\u66f4\u597d\uff0c\u5e76\u5c06\u901a\u8fc7\u591a\u4e2a\u4ee3\u7801\u793a\u4f8b\u6765\u6f14\u793a\u8fd9\u4e00\u70b9\u3002<\/p>\n<h2> \u7406\u89e3isset()\u548cempty() <\/h2>\n<p>\u5728\u6df1\u5165\u7814\u7a76\u7ec6\u8282\u4e4b\u524d\uff0c\u8ba9\u6211\u4eec\u5148\u6f84\u6e05\u4e00\u4e0b\u8fd9\u4e9b\u8bed\u8a00\u7ed3\u6784\u7684\u4f5c\u7528\uff1a<\/p>\n<p>isset()\uff1a\u6b64\u8bed\u8a00\u6784\u9020\u68c0\u67e5\u53d8\u91cf\u662f\u5426\u5df2\u8bbe\u7f6e\u4e14\u4e0d\u4e3a null\u3002\u5982\u679c\u53d8\u91cf\u5b58\u5728\u4e14\u5176\u503c\u4e0d\u4e3a null\uff0c\u5219\u8fd4\u56de true\uff1b\u5426\u5219\uff0c\u8fd4\u56de false\u3002<\/p>\n<pre>$var = 0;\necho isset($var); \/\/ outputs: 1 (true)\n<\/pre>\n<p>empty()\uff1a\u6b64\u8bed\u8a00\u6784\u9020\u786e\u5b9a\u53d8\u91cf\u662f\u5426\u88ab\u89c6\u4e3a\u201c\u7a7a\u201d\u3002\u5982\u679c\u53d8\u91cf\u4e0d\u5b58\u5728\u6216\u8005\u5176\u503c\u7b49\u4e8e false\uff0c\u5219\u8be5\u53d8\u91cf\u88ab\u89c6\u4e3a\u7a7a\u3002\u6839\u636e\u524d\u9762\u63d0\u5230\u7684\u6761\u4ef6\uff0c\u5982\u679c\u53d8\u91cf\u4e3a\u7a7a\uff0cempty() \u8fd4\u56de true\uff1b\u5426\u5219\uff0c\u8fd4\u56de false\u3002<\/p>\n<pre>$var = 0;\necho empty($var); \/\/ outputs: 1 (true)\n<\/pre>\n<h2> \u4e3a\u4ec0\u4e48\u6211\u66f4\u559c\u6b22empty()\uff1f <\/h2>\n<p>\u4f7f\u7528empty()\u76f8\u5bf9\u4e8eisset()\u7684\u4e3b\u8981\u4f18\u70b9\u5728\u4e8e\u5b83\u80fd\u591f\u540c\u65f6\u5904\u7406\u591a\u4e2a\u68c0\u67e5\u3002 empty() \u5c06\u68c0\u67e5\u53d8\u91cf\u662f\u5426\u5df2\u8bbe\u7f6e\u4ee5\u53ca\u5176\u503c\u662f\u5426\u4e3a\u7a7a\uff08\u201c\u201d\u30010\u30010.0\u3001\u201c0\u201d\u3001null\u3001false \u548c\u7a7a\u6570\u7ec4\uff09\u3002\u8fd9\u6837\u5c31\u65e0\u9700\u5355\u72ec\u4f7f\u7528 isset() \u548c\u503c\u68c0\u67e5\uff0c\u4ece\u800c\u964d\u4f4e\u4e86\u4ee3\u7801\u590d\u6742\u6027\u548c\u6f5c\u5728\u9519\u8bef\u3002<\/p>\n<h2> \u4ee3\u7801\u793a\u4f8b 1\uff1a\u68c0\u67e5\u9ed8\u8ba4\u503c <\/h2>\n<pre>$input = $_post['data'] ?? '';\n\n\/\/ using isset()\nif (isset($input) &amp;&amp; $input !== '') {\n    echo \"input is set and not empty.\";\n} else {\n    echo \"input is not set or empty.\";\n}\n\n\/\/ using empty()\nif (!empty($input)) {\n    echo \"input is set and not empty\/falsy.\";\n} else {\n    echo \"input is not set or empty\/falsy.\";\n}\n<\/pre>\n<p>\u5728\u4e0a\u9762\u7684\u793a\u4f8b\u4e2d\uff0cempty() \u901a\u8fc7\u5c06\u5176\u5408\u5e76\u4e3a\u5355\u4e2a\u6761\u4ef6\u6765\u7b80\u5316\u68c0\u67e5\u3002<\/p>\n<h2> \u4ee3\u7801\u793a\u4f8b 2\uff1a\u4f7f\u7528\u6570\u7ec4 <\/h2>\n<p>\u4f7f\u7528\u6570\u7ec4\u65f6\uff0c\u5c24\u5176\u662f\u4f7f\u7528\u53ef\u80fd\u5b58\u5728\u6216\u4e0d\u5b58\u5728\u7684\u952e\u65f6\uff0cempty() \u5bf9\u4e8e\u907f\u514d\u6709\u5173\u672a\u5b9a\u4e49\u7d22\u5f15\u7684\u901a\u77e5\u7279\u522b\u6709\u7528\u3002<\/p>\n<pre>$data = ['username' =&gt; 'johndoe'];\n\n\/\/ using isset()\nif (isset($data['username']) &amp;&amp; $data['username'] !== '') {\n    echo \"username is set and not empty.\";\n} else {\n    echo \"username is missing or empty.\";\n}\n\n\/\/ using empty()\nif (!empty($data['username'])) {\n    echo \"username is set and not empty\/falsy.\";\n} else {\n    echo \"username is missing or empty\/falsy.\";\n}\n<\/pre>\n<h2> \u4ee3\u7801\u793a\u4f8b 3\uff1a\u5e03\u5c14\u68c0\u67e5 <\/h2>\n<p>\u68c0\u67e5\u5e03\u5c14\u6807\u5fd7\u65f6\uff0c\u5c24\u5176\u662f\u90a3\u4e9b\u53ef\u80fd\u672a\u8bbe\u7f6e\u7684\u6807\u5fd7\u65f6\uff0cempty() \u53ef\u4ee5\u907f\u514d\u989d\u5916\u7684\u6761\u4ef6\u68c0\u67e5\u3002<\/p>\n<pre>$options = ['enabled' =&gt; false];\n\n\/\/ Using isset()\nif (isset($options['enabled']) &amp;&amp; $options['enabled']) {\n    echo \"Feature is enabled.\";\n} else {\n    echo \"Feature is disabled.\";\n}\n\n\/\/ Using empty()\nif (!empty($options['enabled'])) {\n    echo \"Feature is enabled.\";\n} else {\n    echo \"Feature is disabled.\";\n}\n<\/pre>\n<h2> \u7ed3\u8bba <\/h2>\n<p>\u5728 php \u4e2d\uff0c\u4f7f\u7528 empty() \u901a\u5e38\u6bd4 isset() \u66f4\u9ad8\u6548\uff0c\u56e0\u4e3a\u5b83\u5168\u9762\u68c0\u67e5\u53d8\u91cf\u662f\u5426\u5df2\u8bbe\u7f6e\u4e14\u5177\u6709\u975e false \u503c\u3002\u8fd9\u4f7f\u5176\u6210\u4e3a\u51cf\u5c11\u4ee3\u7801\u5197\u957f\u548c\u590d\u6742\u6027\u540c\u65f6\u786e\u4fdd\u68c0\u67e5\u7a33\u5065\u6027\u7684\u7edd\u4f73\u5de5\u5177\u3002\u867d\u7136\u5728\u67d0\u4e9b\u7279\u5b9a\u60c5\u51b5\u4e0b isset() \u662f\u5fc5\u8981\u7684\uff0c\u4f8b\u5982\u533a\u5206 false\u3001null \u548c\u672a\u8bbe\u7f6e\u503c\u65f6\u3002\u4e00\u822c\u6765\u8bf4\uff0cempty() \u4e3a\u5927\u591a\u6570\u7528\u4f8b\u63d0\u4f9b\u4e86\u4e00\u4e2a\u7b80\u5355\u800c\u5f3a\u5927\u7684\u66ff\u4ee3\u65b9\u6848\u3002<\/p>\n<p>\u4eca\u5929\u5173\u4e8e\u300a\u4e3a\u4ec0\u4e48\u6211\u5728 PHP \u4e2d\u4f7f\u7528 empty() \u8bed\u8a00\u7ed3\u6784\u800c\u4e0d\u662f isset()\uff0c\u4f60\u4e5f\u5e94\u8be5\u8fd9\u6837\u505a\u300b\u7684\u5185\u5bb9\u4ecb\u7ecd\u5c31\u5230\u6b64\u7ed3\u675f\uff0c\u5982\u679c\u6709\u4ec0\u4e48\u7591\u95ee\u6216\u8005\u5efa\u8bae\uff0c\u53ef\u4ee5\u5728\u516c\u4f17\u53f7\u4e0b\u591a\u591a\u56de\u590d\u4ea4\u6d41\uff1b\u6587\u4e2d\u82e5\u6709\u4e0d\u6b63\u4e4b\u5904\uff0c\u4e5f\u5e0c\u671b\u56de\u590d\u7559\u8a00\u4ee5\u544a\u77e5\uff01<\/p>\n<p> \u7248\u672c\u58f0\u660e \u672c\u6587\u8f6c\u8f7d\u4e8e\uff1adev.to \u5982\u6709\u4fb5\u72af\uff0c\u8bf7\u8054\u7cfb \u5220\u9664<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e3a\u4ec0\u4e48\u6211\u5728 PHP \u4e2d\u4f7f\u7528 em&#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-202458","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/202458","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=202458"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/202458\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=202458"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=202458"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=202458"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}