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<!DOCTYPE html>  <html lang="en"> <head> <meta charset="utf-8"> <title>CanJS - beforeremove</title> <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no"> <link rel="stylesheet" type="text/css" href="../static/bundles/bit-docs-site/static.css"> <link rel="shortcut icon" sizes="16x16 24x24 32x32 48x48 64x64" href="/docs/images/canjs_favicon.ico"> <link rel="apple-touch-icon" sizes="57x57" href="../../docs/images/canjs_favicon_57x57.png"> <link rel="apple-touch-icon-precomposed" sizes="57x57" href="../../docs/images/canjs_favicon_57x57.png"> <link rel="apple-touch-icon" sizes="72x72" href="../../docs/images/canjs_favicon_72x72.png"> <link rel="apple-touch-icon" sizes="114x114" href="../../docs/images/canjs_favicon_114x114.png"> <link rel="apple-touch-icon" sizes="120x120" href="../../docs/images/canjs_favicon_128x128.png"> <link rel="apple-touch-icon" sizes="144x144" href="../../docs/images/canjs_favicon_144x144.png"> <link rel="apple-touch-icon" sizes="152x152" href="../../docs/images/canjs_favicon_152x152.png"> <meta content="yes" name="apple-mobile-web-app-capable"> <meta name="apple-mobile-web-app-status-bar-style" content="white-translucent"> <script> (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o), m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,'script','https://www.google-analytics.com/analytics.js','ga'); ga('create', 'UA-2302003-11', 'auto'); ga('send', 'pageview'); </script> </head> <body> <input type="checkbox" id="nav-trigger" class="nav-trigger"/> <label for="nav-trigger">Menu</label> <div id="everything"> <div id="left" class="column"> <div class="top-left"> <div class="brand"> <div class="logo"> <a href="../../index.html" alt="CanJS"></a> <div class="dropdown project-dropdown"> <a href="https://donejs.com/">DoneJS</a> <a href="http://stealjs.com/">StealJS</a> <a href="http://jquerypp.com/">jQuery ++</a> <a href="https://funcunit.com/">FuncUnit</a> <a href="http://documentjs.com/">DocumentJS</a> </div> </div> <div class="version"> <div class="version-number"> 3.0.0 </div> <div class="dropdown version-dropdown"> <a href="https://v2.canjs.com">2.3.27</a> </div> </div> </div> <div class="search-bar"> <p>   </p> </div> </div> <div class="bottom-left"> <div class="social-side-container"> <ul class="social-side"> <li> <a class="header-mobile github" href="https://github.com/canjs/canjs" target="_blank"><img class="social-icon-small" src="../../docs/images/github.png">Github</a> </li> <li> <a class="header-mobile twitter" href="https://twitter.com/canjs" target="_blank"><img class="social-icon-small" src="../../docs/images/twitter.png">Twitter</a> </li> </ul> <ul class="social-side"> <li> <a class="header-mobile" href="https://gitter.im/canjs/canjs" target="_blank">Chat</a> </li> <li> <a class="header-mobile" href="http://forums.donejs.com/c/canjs" target="_blank">Forum</a> </li> </ul> </div> <ul> <li class=" "> <a class="page" href="../guides.html" title="Welcome to CanJS! 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It can be listened to within a component's can-component.prototype.events object or on a component element with can-stache-bindings.event bindings. This is an additional special event only on component elements. inserted and removed events are available on all elements."> beforeremove </a> </li> </ul> </li> </ul> </li> <li class=" "> <a class="module" href="../can-compute.html" title="Create an observable value."> can-compute </a> </li> <li class=" "> <a class="module" href="../can-connect.html" title="can-connect provides persisted data middleware. 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It can be listened to within a component's <a href="../can-component.prototype.events.html" title="Listen to events on elements and observables.">events</a> object or on a component element with <a href="../can-stache-bindings.event.html" title="Response to events on elements or component ViewModels.">(event)</a> bindings. This is an additional special event only on component elements. <a href="../can-util/dom/events/inserted/inserted.html" title="This event fires when the bound element is added to the DOM.">inserted</a> and <a href="../can-util/dom/events/removed/removed.html" title="This event fires when the bound element is detached or destroyed.">removed</a> events are available on all elements.</p> </section> </section> <section class="on-this-page-table"> </section> <section class="title-footer"> <ul class="title-links">  <li><a href="//github.com/canjs/can-component/tree/v3.0.2/docs/beforeremove.md">source</a></li>   </ul> </section> <div class="signature"> <h2 class="signature-title"> <code>"{element} beforeremove": function(element, event)</code> </h2> <p>Listens to when the component element is removed.<br /> This is commonly used for cleaning up and tearing down a component.</p> <p>For example, the following might remove the component's ViewModel from a parent component's ViewModel:</p> <pre><code class="language-js">events: { "{element} beforeremove": function(){ canViewModel(this.element.parentNode) .removePanel(this.viewModel); } } </code></pre> <div class="parameters"> <h3 class="parameters-title">Parameters</h3> <ol> <li><b>element</b> <code>{HTMLElement}</code>: <p>The component element.</p> </li> <li><b>event</b> <code>{Event}</code>: <p>The <code>beforeremove</code> event object.</p> </li> </ol> </div> </div> <div class="signature"> <h2 class="signature-title"> <code>($beforeremove)="CALL_EXRESSION"</code> </h2> <p>Uses <a href="../can-stache-bindings.event.html" title="Response to events on elements or component ViewModels.">(event)</a> bindings to listen for a component's beforeremove event.</p> <pre><code><my-panel ($beforeremove)="removePanel(%viewModel)"/> </code></pre> <div class="parameters"> <h3 class="parameters-title">Parameters</h3> <ol> <li><b>CALL_EXRESSION</b> <code>{<a href="../can-stache/expressions/call.html" title="">Call Expression</a>}</code>: <p>A call expression that calls some method when the event happens.</p> </li> </ol> </div> </div> <section class="body"> </section> <script type="text/javascript"> var docObject = {"src":{"path":"node_modules/can-component/docs/beforeremove.md"},"description":"\nAn event called only on component's elements before they are removed from the\ndocument if live binding is performing the removal. 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[can-util/dom/events/inserted/inserted]\nand [can-util/dom/events/removed/removed] events are available on all elements.\n","type":"typedef","title":"beforeremove","types":[{"type":"function","returns":{"types":[{"type":"undefined"}]},"params":[]}],"name":"can-component/beforeremove","parent":"can-component.events","signatures":[{"code":"\"{element} beforeremove\": function(element, event)","description":"\n\nListens to when the component element is removed. \nThis is commonly used for cleaning up and tearing down a component.\n\nFor example, the following might remove the component's ViewModel\nfrom a parent component's ViewModel:\n\n```js\nevents: {\n\t\"{element} beforeremove\": function(){\n\t\tcanViewModel(this.element.parentNode)\n\t\t\t.removePanel(this.viewModel);\n\t}\n}\n```\n","params":[{"types":[{"type":"HTMLElement"}],"name":"element","description":"The component element."},{"types":[{"type":"Event"}],"name":"event","description":"The `beforeremove` event object.\n"}]},{"code":"($beforeremove)=\"CALL_EXRESSION\"","description":"\n\nUses [can-stache-bindings.event] bindings to listen for a component's\nbeforeremove event. \n\n```\n<my-panel ($beforeremove)=\"removePanel(%viewModel)\"/>\n```\n","params":[{"types":[{"type":"can-stache/expressions/call"}],"name":"CALL_EXRESSION","description":"A call expression that calls some method when the event happens.\n"}]}],"_curParam":{"types":[{"type":"can-stache/expressions/call"}],"name":"CALL_EXRESSION","description":"A call expression that calls some method when the event happens.\n"},"pathToRoot":"../.."}; </script> </article> <footer><p>CanJS is part of <a href="http://donejs.com" target="_blank">DoneJS</a>. 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