{"id":3316,"date":"2025-06-03T15:38:41","date_gmt":"2025-06-04T08:15:40","guid":{"rendered":"https:\/\/badgameshow.com\/steven\/?p=3316"},"modified":"2025-06-04T15:38:41","modified_gmt":"2025-06-04T08:15:40","slug":"%e5%ad%b8%e7%bf%92python%e4%b8%ad%e7%9a%84get%e5%87%bd%e6%95%b8","status":"publish","type":"post","link":"https:\/\/badgameshow.com\/steven\/python\/%e5%ad%b8%e7%bf%92python%e4%b8%ad%e7%9a%84get%e5%87%bd%e6%95%b8\/","title":{"rendered":"\u6df1\u5165\u5b78\u7fd2 Python \u7684 get() \u51fd\u6578\uff1a\u7528\u6cd5\u3001\u6700\u4f73\u5be6\u8e10\u8207\u5be6\u4f5c\u7bc4\u4f8b"},"content":{"rendered":"<p><meta name=\"keywords\" content=\"Python, get(), \u5b57\u5178\u64cd\u4f5c, Python \u6559\u5b78\"><\/p>\n<h1>\u6df1\u5165\u5b78\u7fd2 Python \u7684 get() \u51fd\u6578<\/h1>\n<p>Python \u7684 `get()` \u51fd\u6578\u662f\u4e00\u500b\u975e\u5e38\u5be6\u7528\u7684\u5de5\u5177\uff0c\u5141\u8a31\u7528\u6236\u5f9e\u5b57\u5178\u4e2d\u5b89\u5168\u5730\u7372\u53d6\u6307\u5b9a\u7684\u503c\uff0c\u800c\u4e0d\u5fc5\u64d4\u5fc3\u9047\u5230\u4e0d\u5b58\u5728\u7684\u9375\u6703\u5c0e\u81f4\u7684\u932f\u8aa4\u3002\u9019\u7bc7\u6587\u7ae0\u5c07\u4ecb\u7d39 `get()` \u51fd\u6578\u7684\u6700\u65b0\u8a9e\u6cd5\u3001\u4f7f\u7528\u7bc4\u4f8b\u4ee5\u53ca\u4e00\u4e9b\u6700\u4f73\u5be6\u8e10\uff0c\u5e6b\u52a9\u4f60\u66f4\u6709\u6548\u5730\u4f7f\u7528 Python\u3002<\/p>\n<h2>get() \u51fd\u6578\u7684\u8a9e\u6cd5<\/h2>\n<p>`get()` \u51fd\u6578\u7684\u57fa\u672c\u8a9e\u6cd5\u5982\u4e0b\uff1a<\/p>\n<pre class=\"brush: python\">\ndict.get(key[, default])\n<\/pre>\n<p>&#8211; `key`\uff1a\u4f60\u60f3\u8981\u7372\u53d6\u7684\u9375\u3002<br \/>\n&#8211; `default`\uff1a\u53ef\u9078\u53c3\u6578\uff0c\u7576\u5b57\u5178\u4e2d\u4e0d\u5b58\u5728\u8a72\u9375\u6642\uff0c\u8fd4\u56de\u7684\u503c\u3002\u5982\u679c\u672a\u63d0\u4f9b\uff0c\u5247\u6703\u8fd4\u56de `None`\u3002<\/p>\n<h2>\u4f7f\u7528\u7bc4\u4f8b<\/h2>\n<p>\u8b93\u6211\u5011\u4f86\u770b\u770b\u5982\u4f55\u4f7f\u7528 `get()` \u51fd\u6578\u3002\u5047\u8a2d\u6211\u5011\u6709\u4e00\u500b\u5b57\u5178\uff0c\u5305\u542b\u4e00\u4e9b\u57fa\u672c\u8cc7\u6599\uff1a<\/p>\n<pre class=\"brush: python\">\nmy_dict = {\n    'name': 'John',\n    'age': 20\n}\n<\/pre>\n<p>\u5982\u679c\u6211\u5011\u60f3\u8981\u53d6\u5f97 `name` \u7684\u503c\uff0c\u53ef\u4ee5\u9019\u6a23\u4f7f\u7528 `get()` \u51fd\u6578\uff1a<\/p>\n<pre class=\"brush: python\">\nname = my_dict.get('name')\nprint(name)  # \u8f38\u51fa: John\n<\/pre>\n<p>\u5982\u679c\u6211\u5011\u8a66\u5716\u7372\u53d6\u4e00\u500b\u4e0d\u5b58\u5728\u7684\u9375\uff0c\u4f8b\u5982 `gender`\uff0c\u53ef\u4ee5\u6307\u5b9a\u4e00\u500b `default` \u503c\uff1a<\/p>\n<pre class=\"brush: python\">\ngender = my_dict.get('gender', 'Unknown')\nprint(gender)  # \u8f38\u51fa: Unknown\n<\/pre>\n<p>\u9019\u6a23\uff0c\u5373\u4f7f `gender` \u4e0d\u5b58\u5728\uff0c\u4e5f\u4e0d\u6703\u62cb\u51fa\u932f\u8aa4\uff0c\u800c\u662f\u8fd4\u56de\u9810\u8a2d\u503c `&#8217;Unknown&#8217;`\u3002<\/p>\n<h2>\u4f7f\u7528 get() \u51fd\u6578\u6aa2\u67e5\u9375\u7684\u5b58\u5728\u6027<\/h2>\n<p>`get()` \u51fd\u6578\u9084\u53ef\u4ee5\u7528\u4f86\u6aa2\u67e5\u5b57\u5178\u4e2d\u662f\u5426\u5b58\u5728\u67d0\u500b\u9375\uff0c\u9019\u6a23\u53ef\u4ee5\u6709\u6548\u907f\u514d `KeyError` \u932f\u8aa4\u3002\u4f8b\u5982\uff1a<\/p>\n<pre class=\"brush: python\">\nif 'name' in my_dict:\n    print('Name exists!')\nelse:\n    print('Name does not exist!')\n<\/pre>\n<p>\u6211\u5011\u53ef\u4ee5\u4f7f\u7528 `get()` \u4f86\u9054\u6210\u76f8\u540c\u7684\u76ee\u7684\uff1a<\/p>\n<pre class=\"brush: python\">\nif my_dict.get('name'):\n    print('Name exists!')\nelse:\n    print('Name does not exist!')\n<\/pre>\n<p>\u9019\u6bb5\u7a0b\u5f0f\u78bc\u80fd\u66f4\u7c21\u6f54\u5730\u6aa2\u67e5\u9375\u7684\u5b58\u5728\u6027\u3002<\/p>\n<h2>\u6700\u4f73\u5be6\u8e10\u8207\u932f\u8aa4\u6392\u9664<\/h2>\n<p>1. **\u907f\u514d\u4f7f\u7528 `None` \u4f5c\u70ba `default` \u503c**\uff1a\u5982\u679c\u5728\u5b57\u5178\u4e2d\u6709\u53ef\u80fd\u5b58\u5728 `None` \u503c\uff0c\u8acb\u9078\u64c7\u5176\u4ed6\u660e\u78ba\u7684 `default` \u503c\uff0c\u4ee5\u514d\u6df7\u6dc6\u3002<br \/>\n2. **\u4f7f\u7528\u5b57\u5178\u7684 `setdefault()` \u65b9\u6cd5**\uff1a\u5982\u679c\u4f60\u5e0c\u671b\u5728\u7372\u53d6\u9375\u7684\u540c\u6642\u9084\u80fd\u8a2d\u7f6e\u4e00\u500b\u9ed8\u8a8d\u503c\uff0c\u53ef\u4ee5\u8003\u616e\u4f7f\u7528 `setdefault()` \u65b9\u6cd5\u3002<\/p>\n<h2>\u5ef6\u4f38\u61c9\u7528<\/h2>\n<p>`get()` \u51fd\u6578\u5728\u8a31\u591a\u61c9\u7528\u4e2d\u90fd\u975e\u5e38\u6709\u6548\uff0c\u7279\u5225\u662f\u5728\u8655\u7406\u5f9e API \u7372\u53d6\u7684 JSON \u6578\u64da\u6642\uff0c\u56e0\u70ba\u9019\u4e9b\u6578\u64da\u7d50\u69cb\u901a\u5e38\u4e0d\u7a69\u5b9a\u4e14\u53ef\u80fd\u7f3a\u5c11\u67d0\u4e9b\u9375\u3002\u900f\u904e `get()` \u51fd\u6578\uff0c\u6211\u5011\u53ef\u4ee5\u5b89\u5168\u5730\u7372\u53d6\u6240\u9700\u7684\u6578\u64da\uff0c\u4e26\u63d0\u4f9b\u9ed8\u8a8d\u503c\u4f86\u8655\u7406\u7f3a\u5931\u7684\u60c5\u6cc1\u3002<\/p>\n<p>\u5982\u679c\u4f60\u5c0d Python \u7684\u5b57\u5178\u64cd\u4f5c\u611f\u8208\u8da3\uff0c\u6b61\u8fce\u53c3\u8003\u66f4\u591a\u76f8\u95dc\u7684\u6559\u5b78\u6587\u7ae0\uff0c\u50cf\u662f [\u9019\u88e1\u7684\u5b57\u5178\u6df1\u5165\u89e3\u6790](https:\/\/vocus.cc\/article\/123456)\uff01<\/p>\n<h2>\u7d50\u8ad6<\/h2>\n<p>Python \u7684 `get()` \u51fd\u6578\u662f\u4e00\u500b\u7c21\u55ae\u537b\u5f37\u5927\u7684\u5de5\u5177\uff0c\u53ef\u4ee5\u5e6b\u52a9\u6211\u5011\u5728\u9032\u884c\u5b57\u5178\u64cd\u4f5c\u6642\u907f\u514d\u6f5b\u5728\u7684\u932f\u8aa4\uff0c\u4e26\u63d0\u4f9b\u66f4\u5b89\u5168\u7684\u7372\u53d6\u65b9\u5f0f\u3002\u7121\u8ad6\u662f\u5728\u65e5\u5e38\u958b\u767c\u4e2d\u9084\u662f\u9762\u5c0d\u8907\u96dc\u7684\u6578\u64da\u7d50\u69cb\uff0c\u719f\u7df4\u638c\u63e1 `get()` \u51fd\u6578\u90fd\u5c07\u8b93\u4f60\u7684\u7a0b\u5f0f\u78bc\u66f4\u52a0\u5065\u58ef\u3002<\/p>\n<h2>Q&#038;A\uff08\u5e38\u898b\u554f\u984c\u89e3\u7b54\uff09<\/h2>\n<p>**Q1: `get()` \u51fd\u6578\u8fd4\u56de `None` \u662f\u4ec0\u9ebc\u610f\u601d\uff1f**<br \/>\nA1: \u7576\u4f7f\u7528 `get()` \u51fd\u6578\u6642\uff0c\u5982\u679c\u6307\u5b9a\u7684\u9375\u4e0d\u5b58\u5728\u4e14\u672a\u63d0\u4f9b `default` \u503c\uff0c\u5247\u6703\u8fd4\u56de `None`\u3002<\/p>\n<p>**Q2: \u6211\u53ef\u4ee5\u4f7f\u7528 `get()` \u51fd\u6578\u4f86\u66f4\u65b0\u5b57\u5178\u4e2d\u7684\u503c\u55ce\uff1f**<br \/>\nA2: \u4e0d\u53ef\u4ee5\uff0c`get()` \u51fd\u6578\u50c5\u7528\u65bc\u7372\u53d6\u503c\uff0c\u82e5\u8981\u66f4\u65b0\u5b57\u5178\u4e2d\u7684\u503c\uff0c\u61c9\u4f7f\u7528\u76f4\u63a5\u8ce6\u503c\u7684\u65b9\u5f0f\u3002<\/p>\n<p>**Q3: \u4f7f\u7528 `get()` \u51fd\u6578\u662f\u5426\u6703\u5f71\u97ff\u5b57\u5178\u7684\u6027\u80fd\uff1f**<br \/>\nA3: `get()` \u51fd\u6578\u7684\u6027\u80fd\u5f71\u97ff\u5fae\u4e4e\u5176\u5fae\uff0c\u9069\u7528\u65bc\u5927\u591a\u6578\u60c5\u6cc1\u3002\u5c0d\u65bc\u5927\u5b57\u5178\uff0c\u4f7f\u7528 `get()` \u51fd\u6578\u4ecd\u7136\u662f\u9ad8\u6548\u7684\u9078\u64c7\u3002<\/p>\n<p>&#8212;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5b78\u7fd2Python\u4e2d\u7684get()\u51fd\u6578\uff0c\u53ef\u4ee5\u8b93\u4f60\u66f4\u8f15\u9b06\u5730\u7372\u53d6\u5b57\u5178\u4e2d\u7684\u503c\uff0c\u800c\u4e0d\u7528\u64d4\u5fc3KeyError\u7684\u554f\u984c\u3002\u672c\u6587\u5c07\u4ecb\u7d39get()\u51fd\u6578\u7684\u4f7f\u7528\u65b9\u6cd5\uff0c\u4ee5\u53ca\u5982\u4f55\u4f7f\u7528\u5b83\u4f86\u63d0\u9ad8\u4f60\u7684Python\u7a0b\u5e8f\u7684\u53ef\u8b80\u6027\u548c\u53ef\u7dad\u8b77\u6027\u3002<\/p>\n","protected":false},"author":1,"featured_media":2518,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[18],"tags":[15],"class_list":["post-3316","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-python","tag-python"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/badgameshow.com\/steven\/wp-content\/uploads\/2022\/12\/DALL\u00b7E-2022-12-28-14.25.55-\u62f7\u8c9d2.png","jetpack-related-posts":[],"jetpack_shortlink":"https:\/\/wp.me\/pcFK27-Ru","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/posts\/3316","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/comments?post=3316"}],"version-history":[{"count":2,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/posts\/3316\/revisions"}],"predecessor-version":[{"id":12868,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/posts\/3316\/revisions\/12868"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/media\/2518"}],"wp:attachment":[{"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/media?parent=3316"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/categories?post=3316"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/tags?post=3316"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}