{"id":2503,"date":"2025-05-28T17:21:35","date_gmt":"2025-06-04T10:06:35","guid":{"rendered":"https:\/\/badgameshow.com\/steven\/?p=2503"},"modified":"2025-06-04T17:21:35","modified_gmt":"2025-06-04T10:06:35","slug":"%e6%b7%b1%e5%85%a5%e6%8e%a2%e7%b4%a2-python-%e7%9a%84-list-len-%e8%aa%9e%e6%b3%95","status":"publish","type":"post","link":"https:\/\/badgameshow.com\/steven\/python\/%e6%b7%b1%e5%85%a5%e6%8e%a2%e7%b4%a2-python-%e7%9a%84-list-len-%e8%aa%9e%e6%b3%95\/","title":{"rendered":"\u6df1\u5165\u63a2\u7d22 Python \u7684 List len() \u51fd\u6578\uff1a2025 \u6700\u65b0\u89e3\u6790\u8207\u5be6\u4f5c\u7bc4\u4f8b"},"content":{"rendered":"<h1>\u6df1\u5165\u63a2\u7d22 Python \u7684 List len() \u51fd\u6578\uff1a2025 \u6700\u65b0\u89e3\u6790\u8207\u5be6\u4f5c\u7bc4\u4f8b<\/h1>\n<p>\u5728 Python \u7a0b\u5f0f\u4e2d\uff0c\u4e32\u5217\uff08List\uff09\u662f\u4e00\u7a2e\u975e\u5e38\u5e38\u898b\u7684\u8cc7\u6599\u578b\u614b\uff0c\u53ef\u4ee5\u5132\u5b58\u6709\u5e8f\u7684\u5143\u7d20\u3002\u7576\u4f7f\u7528\u4e32\u5217\u6642\uff0c\u5e38\u5e38\u9700\u8981\u77e5\u9053\u4e32\u5217\u7684\u9577\u5ea6\uff0c\u9019\u6642\u5c31\u53ef\u4ee5\u4f7f\u7528 Python \u7684 <strong>len()<\/strong> \u51fd\u6578\u3002<\/p>\n<p>\u672c\u6587\u5c07\u6df1\u5165\u63a2\u8a0e <strong>len()<\/strong> \u51fd\u6578\u7684\u7528\u6cd5\uff0c\u4e26\u63d0\u4f9b\u5b8c\u6574\u7684\u5be6\u4f5c\u7bc4\u4f8b\u3001\u6ce8\u610f\u4e8b\u9805\u4ee5\u53ca\u5ef6\u4f38\u61c9\u7528\uff0c\u8b93\u8b80\u8005\u80fd\u5920\u5168\u9762\u638c\u63e1\u9019\u500b\u5f37\u5927\u7684\u529f\u80fd\u3002<\/p>\n<h2>\u4ec0\u9ebc\u662f List len() \u51fd\u6578<\/h2>\n<p><strong>len()<\/strong> \u51fd\u6578\u662f Python \u5167\u5efa\u7684\u51fd\u6578\uff0c\u7528\u4f86\u8a08\u7b97\u4e32\u5217\uff08List\uff09\u7684\u9577\u5ea6\u3002\u8a9e\u6cd5\u975e\u5e38\u7c21\u55ae\uff0c\u53ea\u9700\u5728\u62ec\u865f\u4e2d\u8f38\u5165\u4e32\u5217\u7684\u8b8a\u6578\u540d\u7a31\u5373\u53ef\u3002\u4f8b\u5982\uff0c\u5982\u679c\u8981\u8a08\u7b97\u4e32\u5217 <code>fruits<\/code> \u7684\u9577\u5ea6\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u7a0b\u5f0f\u78bc\uff1a<\/p>\n<pre class=\"brush: python\">\nfruits = ['apple', 'banana', 'orange']\nsize = len(fruits)\nprint(size)  # \u8f38\u51fa\uff1a3\n<\/pre>\n<p>\u5728\u9019\u500b\u7bc4\u4f8b\u4e2d\uff0c<code>len(fruits)<\/code> \u6703\u8fd4\u56de\u4e32\u5217 <code>fruits<\/code> \u7684\u9577\u5ea6\uff0c\u5373 3\u3002\u7136\u5f8c\uff0c\u6211\u5011\u5c07\u7d50\u679c\u5b58\u5165\u8b8a\u6578 <code>size<\/code>\uff0c\u4e26\u5229\u7528 <code>print()<\/code> \u51fd\u6578\u986f\u793a\u51fa\u4f86\u3002<\/p>\n<h2>\u5982\u4f55\u4f7f\u7528 List len() \u51fd\u6578<\/h2>\n<p>\u9664\u4e86\u8a08\u7b97\u4e32\u5217\u7684\u9577\u5ea6\uff0c<strong>len()<\/strong> \u51fd\u6578\u9084\u53ef\u4ee5\u7528\u65bc\u5176\u4ed6\u8cc7\u6599\u578b\u614b\uff0c\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n<ul>\n<li>\u8a08\u7b97\u5b57\u4e32\uff08String\uff09\u7684\u9577\u5ea6\uff1a\n<pre class=\"brush: python\">\ntext = \"Hello, World!\"\nsize = len(text)\nprint(size)  # \u8f38\u51fa\uff1a13\n<\/pre>\n<\/li>\n<li>\u8a08\u7b97\u5143\u7d44\uff08Tuple\uff09\u7684\u9577\u5ea6\uff1a\n<pre class=\"brush: python\">\nnumbers = (1, 2, 3, 4, 5)\nsize = len(numbers)\nprint(size)  # \u8f38\u51fa\uff1a5\n<\/pre>\n<\/li>\n<li>\u8a08\u7b97\u5b57\u5178\uff08Dictionary\uff09\u7684\u9577\u5ea6\uff1a\n<pre class=\"brush: python\">\nstudent = {'name': 'John', 'age': 20, 'gender': 'male'}\nsize = len(student)\nprint(size)  # \u8f38\u51fa\uff1a3\n<\/pre>\n<\/li>\n<\/ul>\n<p>\u6b64\u5916\uff0c<strong>len()<\/strong> \u51fd\u6578\u4e5f\u53ef\u4ee5\u7528\u65bc\u96c6\u5408\uff08Set\uff09\u3001\u51b0\u51cd\u96c6\u5408\uff08Frozenset\uff09\u3001\u5e03\u6797\uff08Boolean\uff09\u7b49\u5176\u4ed6\u8cc7\u6599\u578b\u614b\u3002<\/p>\n<h2>List len() \u51fd\u6578\u7684\u4e00\u4e9b\u6ce8\u610f\u4e8b\u9805<\/h2>\n<p>\u5728\u4f7f\u7528 <strong>len()<\/strong> \u51fd\u6578\u6642\uff0c\u9700\u6ce8\u610f\u4ee5\u4e0b\u5e7e\u9ede\uff1a<\/p>\n<ul>\n<li>\u7576\u53c3\u6578\u4e0d\u662f\u4e32\u5217\u6642\uff0c\u6703\u767c\u751f\u932f\u8aa4\uff0c\u4f8b\u5982\uff1a\n<pre class=\"brush: python\">\nsize = len(123)  # \u932f\u8aa4\uff1aTypeError: object of type 'int' has no len()\n<\/pre>\n<\/li>\n<li>\u7576\u53c3\u6578\u662f\u7a7a\u4e32\u5217\u6642\uff0c\u6703\u8fd4\u56de 0\uff0c\u4f8b\u5982\uff1a\n<pre class=\"brush: python\">\nfruits = []\nsize = len(fruits)\nprint(size)  # \u8f38\u51fa\uff1a0\n<\/pre>\n<\/li>\n<li>\u7576\u53c3\u6578\u70ba None \u6642\uff0c\u6703\u767c\u751f\u932f\u8aa4\uff0c\u4f8b\u5982\uff1a\n<pre class=\"brush: python\">\nsize = len(None)  # \u932f\u8aa4\uff1aTypeError: object of type 'NoneType' has no len()\n<\/pre>\n<\/li>\n<\/ul>\n<h2>List len() \u51fd\u6578\u7684\u61c9\u7528\u7bc4\u4f8b<\/h2>\n<p>\u73fe\u5728\uff0c\u6211\u5011\u4f86\u770b\u770b\u4e00\u500b\u5be6\u969b\u7684\u61c9\u7528\u7bc4\u4f8b\u3002\u5047\u8a2d\u6709\u4e00\u500b\u540d\u70ba <code>fruits<\/code> \u7684\u4e32\u5217\uff0c\u88e1\u9762\u5b58\u6709\u591a\u500b\u6c34\u679c\u540d\u7a31\u3002\u5982\u679c\u60f3\u8981\u6c42\u51fa\u4e32\u5217\u4e2d\u6709\u5e7e\u7a2e\u6c34\u679c\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u7a0b\u5f0f\u78bc\uff1a<\/p>\n<pre class=\"brush: python\">\nfruits = ['apple', 'banana', 'orange', 'apple', 'pear', 'banana']\nunique_fruits = set(fruits)  # \u5c07\u4e32\u5217\u8f49\u63db\u6210\u96c6\u5408\uff0c\u81ea\u52d5\u53bb\u9664\u91cd\u8907\u5143\u7d20\nsize = len(unique_fruits)\nprint(f\"\u9019\u500b\u4e32\u5217\u4e2d\u6709 {size} \u7a2e\u6c34\u679c\uff1a{unique_fruits}\")  # \u8f38\u51fa\uff1a\u9019\u500b\u4e32\u5217\u4e2d\u6709 4 \u7a2e\u6c34\u679c\uff1a{'apple', 'banana', 'orange', 'pear'}\n<\/pre>\n<p>\u5728\u6b64\u7bc4\u4f8b\u4e2d\uff0c\u4f7f\u7528 <code>set()<\/code> \u5c07\u4e32\u5217\u8f49\u63db\u70ba\u96c6\u5408\uff0c\u4ee5\u81ea\u52d5\u53bb\u9664\u91cd\u8907\u7684\u5143\u7d20\u3002\u7136\u5f8c\uff0c\u5229\u7528 <code>len()<\/code> \u51fd\u6578\u8a08\u7b97\u96c6\u5408\u7684\u9577\u5ea6\uff0c\u4e26\u5c07\u7d50\u679c\u5b58\u5165\u8b8a\u6578 <code>size<\/code>\u3002\u6700\u5f8c\uff0c\u4f7f\u7528 <code>print()<\/code> \u51fd\u6578\u8f38\u51fa\u7d50\u679c\u3002<\/p>\n<h2>\u5ef6\u4f38\u61c9\u7528<\/h2>\n<p>\u9664\u4e86\u8a08\u7b97\u4e32\u5217\u7684\u9577\u5ea6\uff0c<strong>len()<\/strong> \u51fd\u6578\u5728\u8cc7\u6599\u8655\u7406\u4e2d\u9084\u53ef\u4ee5\u7528\u4f86\u6aa2\u67e5\u8cc7\u6599\u7684\u5b8c\u6574\u6027\u3002\u4f8b\u5982\uff0c\u5728\u6578\u64da\u5206\u6790\u904e\u7a0b\u4e2d\uff0c\u78ba\u4fdd\u6578\u64da\u96c6\u7684\u9577\u5ea6\u7b26\u5408\u9810\u671f\u662f\u975e\u5e38\u91cd\u8981\u7684\u3002\u4f60\u53ef\u4ee5\u4f7f\u7528 <strong>len()<\/strong> \u51fd\u6578\u4f86\u78ba\u4fdd\u6578\u64da\u96c6\u5728\u9032\u884c\u8a08\u7b97\u6216\u5efa\u6a21\u4e4b\u524d\u662f\u5b8c\u6574\u7684\u3002<\/p>\n<h2>\u7d50\u8ad6<\/h2>\n<p>\u900f\u904e\u672c\u6587\u7684\u4ecb\u7d39\uff0c\u4f60\u73fe\u5728\u61c9\u8a72\u5c0d Python \u7684 <strong>len()<\/strong> \u51fd\u6578\u6709\u4e86\u66f4\u6df1\u5165\u7684\u4e86\u89e3\u3002\u7121\u8ad6\u662f\u5728\u8a08\u7b97\u4e32\u5217\u3001\u5b57\u4e32\u9084\u662f\u5176\u4ed6\u8cc7\u6599\u578b\u614b\u7684\u9577\u5ea6\uff0c<strong>len()<\/strong> \u51fd\u6578\u90fd\u80fd\u5920\u63d0\u4f9b\u7c21\u55ae\u800c\u6709\u6548\u7684\u89e3\u6c7a\u65b9\u6848\u3002<\/p>\n<p>\u5982\u9700\u9032\u4e00\u6b65\u4e86\u89e3 Python \u7684\u66f4\u591a\u6559\u5b78\u5167\u5bb9\uff0c\u6b61\u8fce\u53c3\u8003\u9019\u7bc7\u6587\u7ae0 [Python \u57fa\u790e\u5165\u9580](https:\/\/vocus.cc), \u9019\u5c07\u5c0d\u4f60\u5b78\u7fd2 Python \u6709\u5f88\u5927\u5e6b\u52a9\u3002<\/p>\n<h2>Q&#038;A\uff08\u5e38\u898b\u554f\u984c\u89e3\u7b54\uff09<\/h2>\n<h3>Q1: len() \u51fd\u6578\u80fd\u5426\u7528\u65bc\u81ea\u5b9a\u7fa9\u7269\u4ef6\uff1f<\/h3>\n<p>A1: \u53ef\u4ee5\u3002\u5982\u679c\u81ea\u5b9a\u7fa9\u7684\u7269\u4ef6\u4e2d\u5be6\u73fe\u4e86 `__len__` \u65b9\u6cd5\uff0c\u5247\u53ef\u4ee5\u4f7f\u7528 <strong>len()<\/strong> \u51fd\u6578\u4f86\u8a08\u7b97\u5176\u9577\u5ea6\u3002<\/p>\n<h3>Q2: \u4f7f\u7528 len() \u51fd\u6578\u8a08\u7b97\u7a7a\u5217\u8868\u7684\u9577\u5ea6\u6703\u8fd4\u56de\u4ec0\u9ebc\uff1f<\/h3>\n<p>A2: \u4f7f\u7528 <strong>len()<\/strong> \u51fd\u6578\u8a08\u7b97\u7a7a\u5217\u8868\u7684\u9577\u5ea6\u6703\u8fd4\u56de 0\u3002<\/p>\n<h3>Q3: len() \u51fd\u6578\u662f\u5426\u53ef\u4ee5\u7528\u65bc\u8a08\u7b97\u5b57\u5178\u7684\u9375\u7684\u6578\u91cf\uff1f<\/h3>\n<p>A3: \u662f\u7684\uff0c\u4f7f\u7528 <strong>len()<\/strong> \u51fd\u6578\u53ef\u4ee5\u8a08\u7b97\u5b57\u5178\u4e2d\u7684\u9375\u7684\u6578\u91cf\uff0c\u4e5f\u5c31\u662f\u5b57\u5178\u7684\u9577\u5ea6\u3002<br \/>\n&#8212;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6df1\u5165\u63a2\u7d22 Python \u7684 List len() &#8230;<\/p>\n","protected":false},"author":1,"featured_media":2518,"comment_status":"open","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":[],"class_list":["post-2503","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-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-En","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/posts\/2503","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=2503"}],"version-history":[{"count":5,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/posts\/2503\/revisions"}],"predecessor-version":[{"id":13068,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/posts\/2503\/revisions\/13068"}],"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=2503"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/categories?post=2503"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/badgameshow.com\/steven\/wp-json\/wp\/v2\/tags?post=2503"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}