{"id":53109,"date":"2024-12-03T15:51:52","date_gmt":"2024-12-03T07:51:52","guid":{"rendered":"https:\/\/fwq.ai\/blog\/53109\/"},"modified":"2024-12-03T15:51:52","modified_gmt":"2024-12-03T07:51:52","slug":"javascript-%e4%b8%ad%e7%9a%84-queryselector-%e4%b8%8e-queryselectorall","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/53109\/","title":{"rendered":"javascript \u4e2d\u7684 querySelector \u4e0e querySelectorAll"},"content":{"rendered":"

<\/b> <\/p>\n

javascript \u4e2d\u7684 querySelector \u4e0e querySelectorAll<\/h1>\n

<\/i>\u6536\u85cf<\/span> <\/p>\n

\u5c0f\u4f19\u4f34\u4eec\u6709\u6ca1\u6709\u89c9\u5f97\u5b66\u4e60\u6587\u7ae0<\/span>\u5f88\u6709\u610f\u601d\uff1f\u6709\u610f\u601d\u5c31\u5bf9\u4e86\uff01\u4eca\u5929\u5c31\u7ed9\u5927\u5bb6\u5e26\u6765\u300ajavascript \u4e2d\u7684 querySelector \u4e0e querySelectorAll\u300b<\/span>\uff0c\u4ee5\u4e0b\u5185\u5bb9\u5c06\u4f1a\u6d89\u53ca\u5230<\/span>\uff0c\u82e5\u662f\u5728\u5b66\u4e60\u4e2d\u5bf9\u5176\u4e2d\u90e8\u5206\u77e5\u8bc6\u70b9\u6709\u7591\u95ee\uff0c\u6216\u8bb8\u770b\u4e86\u672c\u6587\u5c31\u80fd\u5e2e\u5230\u4f60\uff01<\/p>\n

\"javascript<\/p>\n

queryselector \u4e0e queryselectorall \u90fd\u7528\u4e8e\u9009\u62e9\u548c\u64cd\u4f5c dom \u5143\u7d20\uff0c\u4f46\u5b83\u4eec\u6709\u4e00\u4e9b\u4e0d\u540c\u7684\u884c\u4e3a<\/em><\/p>\n

1.queryselector<\/strong>
\u8fd4\u56de dom \u4e2d\u6ee1\u8db3 css \u9009\u62e9\u5668\u7684\u7b2c\u4e00\u4e2a\u5339\u914d\u5143\u7d20\u3002\u5982\u679c\u672a\u627e\u5230\u5339\u914d\u9879\uff0c\u5219\u8fd4\u56de null\u3002<\/p>\n

<nav>\n<!doctype html>\n<html>\n<body>\n<nav class='nav'>\n<a href=\"\/html\/\">html<\/a> |\n<a href=\"\/css\/\">css<\/a> |\n<a href=\"\/js\/\">javascript<\/a> |\n<a href=\"\/python\/\">python<\/a>\n<\/nav>\n\n<script>\n\nconst link  = document.queryselector(\"a\")\nconsole.log(link); \/\/ <a href=\"\/html\/\">html<\/a>\n\n<\/script>\n\n<\/body>\n<\/html>\n<\/pre>\n
\u5728\u4e0a\u9762\u7684\u4ee3\u7801\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230\u5728\u811a\u672c\u6807\u7b7e\u5185\u6211\u9009\u62e9\u4e86\u4e00\u4e2a\u6807\u7b7e\uff0c\u5e76\u4e14\u6211\u4eec\u53ea\u83b7\u5f97\u7b2c\u4e00\u4e2a\u5339\u914d\u5143\u7d20\uff0c\u800c\u4e0d\u662f\u5168\u90e8\u3002<\/p>\n
2.queryselectorall<\/strong>
 \u4ee5 nodelist \u7684\u5f62\u5f0f\u8fd4\u56de\u6240\u6709\u5339\u914d\u7684\u5143\u7d20\uff0cnodelist \u662f\u5143\u7d20\u7684\u96c6\u5408\u3002\u5982\u679c\u672a\u627e\u5230\u5339\u914d\u9879\uff0c\u5219\u8fd4\u56de\u4e00\u4e2a\u7a7a nodelist\u3002<\/p>\n
<nav>\n<!DOCTYPE html>\n<html>\n<body>\n<nav class='nav'>\n<a href=\"\/html\/\">HTML<\/a> |\n<a href=\"\/css\/\">CSS<\/a> |\n<a href=\"\/js\/\">JavaScript<\/a> |\n<a href=\"\/python\/\">Python<\/a>\n<\/nav>\n\n<script>\n\nconst link  = document.querySelectorAll(\"a\")\nconsole.log(link); \/\/ \/\/ [object NodeList] (4) [<a\/>,<a\/>,<a\/>,<a\/>]\n\n<\/script>\n\n<\/body>\n<\/html>\n<\/pre>\n
\u5728\u4e0a\u9762\u7684\u4ee3\u7801\u793a\u4f8b\u4e2d\uff0c\u6211\u4eec\u53ef\u4ee5\u770b\u5230\u5728\u811a\u672c\u6807\u7b7e\u5185\u6211\u9009\u62e9\u4e86\u4e00\u4e2a\u6807\u7b7e\uff0c\u5e76\u4e14\u6211\u4eec\u5c06\u6240\u6709\u5339\u914d\u7684\u5143\u7d20\u4f5c\u4e3a nodelist \u83b7\u53d6\u3002<\/p>\n
\u5230\u8fd9\u91cc\uff0c\u6211\u4eec\u4e5f\u5c31\u8bb2\u5b8c\u4e86\u300ajavascript \u4e2d\u7684 querySelector \u4e0e querySelectorAll\u300b\u7684\u5185\u5bb9\u4e86\u3002\u4e2a\u4eba\u8ba4\u4e3a\uff0c\u57fa\u7840\u77e5\u8bc6\u7684\u5b66\u4e60\u548c\u5de9\u56fa\uff0c\u662f\u4e3a\u4e86\u66f4\u597d\u7684\u5c06\u5176\u8fd0\u7528\u5230\u9879\u76ee\u4e2d\uff0c\u6b22\u8fce\u5173\u6ce8\u7c73\u4e91\u516c\u4f17\u53f7\uff0c\u5e26\u4f60\u4e86\u89e3\u66f4\u591a\u5173\u4e8e\u7684\u77e5\u8bc6\u70b9\uff01<\/p>\n
      \u7248\u672c\u58f0\u660e \u672c\u6587\u8f6c\u8f7d\u4e8e\uff1adev.to \u5982\u6709\u4fb5\u72af\uff0c\u8bf7\u8054\u7cfb\u5220\u9664    <\/p>\n
\n
<\/dt>\n
\n   \u6b63\u5219\u8868\u8fbe\u5f0f\u5339\u914d\u5c0f\u62ec\u53f7\u5185\u7684\u5185\u5bb9\uff1a\u4e3a\u4f55 re.findall() \u51fd\u6570\u7ed3\u679c\u4e0d\u540c\uff1f\n <\/dd>\n<\/dl>\n","protected":false},"excerpt":{"rendered":"
javascript \u4e2d\u7684 querySelector \u4e0e querySelectorAll \u6536\u85cf \u5c0f\u4f19\u4f34\u4eec\u6709\u6ca1\u6709\u89c9\u5f97\u5b66\u4e60\u6587\u7ae0\u5f88\u6709\u610f\u601d\uff1f\u6709\u610f\u601d\u5c31\u5bf9\u4e86\uff01\u4eca\u5929\u5c31\u7ed9\u5927\u5bb6\u5e26\u6765\u300ajavascript \u4e2d\u7684 querySelector \u4e0e querySelectorAll\u300b\uff0c\u4ee5\u4e0b\u5185\u5bb9\u5c06\u4f1a\u6d89\u53ca\u5230\uff0c\u82e5\u662f\u5728\u5b66\u4e60\u4e2d\u5bf9\u5176\u4e2d\u90e8\u5206\u77e5\u8bc6\u70b9\u6709\u7591\u95ee\uff0c\u6216\u8bb8\u770b\u4e86\u672c\u6587\u5c31\u80fd\u5e2e\u5230\u4f60\uff01 queryselector \u4e0e queryselectorall \u90fd\u7528\u4e8e\u9009\u62e9\u548c\u64cd\u4f5c dom \u5143\u7d20\uff0c\u4f46\u5b83\u4eec\u6709\u4e00\u4e9b\u4e0d\u540c\u7684\u884c\u4e3a 1.queryselector \u8fd4\u56de dom \u4e2d\u6ee1\u8db3 css \u9009\u62e9\u5668\u7684\u7b2c\u4e00\u4e2a\u5339\u914d\u5143\u7d20\u3002\u5982\u679c\u672a\u627e\u5230\u5339\u914d\u9879\uff0c\u5219\u8fd4\u56de null\u3002 <nav> <!doctype html> <html> <body> <nav class=’nav’> <a href=”\/html\/”>html<\/a> | <a href=”\/css\/”>css<\/a> | <a href=”\/js\/”>javascript<\/a> | <a href=”\/python\/”>python<\/a> <\/nav> <script> const link = document.queryselector(“a”) console.log(link); \/\/ <a href=”\/html\/”>html<\/a> <\/script> <\/body> <\/html> […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-53109","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/53109","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=53109"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/53109\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=53109"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=53109"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=53109"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}