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{"id":4004,"date":"2022-03-26T10:56:36","date_gmt":"2022-03-26T10:56:36","guid":{"rendered":"https:\/\/www.wikitechy.com\/interview-questions\/?p=4004"},"modified":"2022-05-04T07:05:21","modified_gmt":"2022-05-04T07:05:21","slug":"what-is-a-ref-how-do-you-use-it","status":"publish","type":"post","link":"https:\/\/www.wikitechy.com\/interview-questions\/reactjs\/what-is-a-ref-how-do-you-use-it\/","title":{"rendered":"What is a ref ? How do you use it ?"},"content":{"rendered":"<ul>\n<li style=\"text-align: justify;\">It is a function provided by React to access the DOM element and the React element that you might have created on your own.<\/li>\n<li style=\"text-align: justify;\">In React, a ref is a <strong>reference to a DOM element.<\/strong><\/li>\n<li style=\"text-align: justify;\">It can be immediately placed in a variable.<\/li>\n<li style=\"text-align: justify;\">They are created with the help of useRef<\/li>\n<li style=\"text-align: justify;\">This variable is then passed to a given React element (not a component) to get a reference to the underlying DOM element (that is, div, span, and so on).<\/li>\n<li style=\"text-align: justify;\">Properties are now available on the element itself.<\/li>\n<li style=\"text-align: justify;\">Refs are often referred to as an &#8220;escape hatch&#8221; to be able to work with a DOM element directly.<\/li>\n<li style=\"text-align: justify;\">They allow us to do certain operations that can&#8217;t be done through React otherwise, such as clearing or focusing an input.<\/li>\n<\/ul>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"alignnone size-full wp-image-4276 aligncenter\" src=\"https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/03\/reactjs-ref.png\" alt=\"\" width=\"758\" height=\"483\" srcset=\"https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/03\/reactjs-ref.png 758w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/03\/reactjs-ref-300x191.png 300w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/03\/reactjs-ref-390x249.png 390w\" sizes=\"(max-width: 758px) 100vw, 758px\" \/><\/p>\n<p><strong>For Example,<\/strong><\/p>\n<div class=\"code-embed-wrapper\"> <div class=\"code-embed-infos\"> <\/div> <pre class=\"language-markup code-embed-pre line-numbers\"  data-start=\"1\" data-line-offset=\"0\"><code class=\"language-markup code-embed-code\">\/\/ using refs<br\/><br\/>class App extends React.Component {<br\/><br\/>\u00a0constructor(){<br\/><br\/>\u00a0\u00a0super();<br\/><br\/>\u00a0\u00a0this.state = { sayings: &quot;&quot;};<br\/><br\/>\u00a0}<br\/><br\/>\u00a0update(e){<br\/><br\/>\u00a0\u00a0this.setState({ sayings: this.refs.anything.value});<br\/><br\/>\u00a0}<br\/><br\/>\u00a0render(){<br\/><br\/>\u00a0\u00a0return (<br\/><br\/>\u00a0\u00a0\u00a0&lt;div&gt;<br\/><br\/>\u00a0\u00a0\u00a0\u00a0Welcome to Kaashiv &lt;input type=&quot;text&quot; ref=&quot;anything&quot;<br\/><br\/>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0onChange = {this.update.bind(this)}\/&gt;<br\/><br\/>\u00a0\u00a0\u00a0&lt;br\/&gt;<br\/><br\/>\u00a0\u00a0\u00a0&lt;em&gt;{this.state.sayings}&lt;\/em&gt;<br\/><br\/>\u00a0\u00a0&lt;\/div&gt;<br\/><br\/>\u00a0\u00a0);<br\/><br\/>\u00a0}<br\/><br\/>}<br\/><br\/>\u00a0ReactDOM.render(&lt; App \/&gt;, document.getElementById(&#039;root&#039;));<br\/><br\/>\u00a0<\/code><\/pre> <\/div>\n<p><strong>\u00a0Output:<\/strong><\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-4020 size-full\" src=\"https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/03\/what-is-ref..png\" alt=\"\" width=\"398\" height=\"203\" srcset=\"https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/03\/what-is-ref..png 398w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/03\/what-is-ref.-300x153.png 300w, https:\/\/www.wikitechy.com\/interview-questions\/wp-content\/uploads\/2022\/03\/what-is-ref.-390x199.png 390w\" sizes=\"(max-width: 398px) 100vw, 398px\" \/><\/p>\n","protected":false},"excerpt":{"rendered":"<p>It is a function provided by React to access the DOM element and the React element that you might have created on your own. In React, a ref is a reference to a DOM element. It can be immediately placed in a variable. They are created with the help of useRef This variable is then [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"passster_activate_protection":false,"passster_protect_child_pages":"","passster_protection_type":"password","passster_password":"","passster_activate_overwrite_defaults":"","passster_headline":"","passster_instruction":"","passster_placeholder":"","passster_button":"","passster_id":"","passster_activate_misc_settings":"","passster_redirect_url":"","passster_hide":"no","passster_area_shortcode":"","gtb_hide_title":false,"gtb_wrap_title":false,"gtb_class_title":"","gtb_remove_headerfooter":false,"footnotes":""},"categories":[16542],"tags":[16769,16770,16773,16774,16772,16766,16771,16761,16764,16762,16767,16757,16763,16775,16765,16758,16759,16760,16768],"class_list":["post-4004","post","type-post","status-publish","format-standard","hentry","category-reactjs","tag-example-of-ref-in-react","tag-how-does-ref-work-in-react","tag-how-to-add-ref-in-react","tag-how-to-clear-ref-in-react","tag-how-to-create-ref-in-react","tag-react-get-element-by-id-functional-component","tag-react-useref","tag-ref-in-react","tag-ref-in-react-example","tag-ref-in-react-functional-component","tag-ref-react-hooks","tag-refs-and-the-dom","tag-use-ref-in-react","tag-use-ref-in-react-example","tag-useref-in-react","tag-what-is-ref-in-react","tag-what-is-ref-in-react-hook","tag-what-is-ref-in-react-hook-form","tag-what-is-ref-used-for-in-react"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.6 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>What is a ref ? 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