{"id":67,"date":"2021-01-28T05:37:19","date_gmt":"2021-01-28T05:37:19","guid":{"rendered":"https:\/\/codecasm.com\/blogs\/?p=67"},"modified":"2021-01-28T05:40:45","modified_gmt":"2021-01-28T05:40:45","slug":"javascript-null-vs-undefined","status":"publish","type":"post","link":"https:\/\/codecasm.com\/blogs\/javascript-null-vs-undefined\/","title":{"rendered":"JavaScript : \u2018null\u2019 vs \u2018undefined\u2019"},"content":{"rendered":"\n

Difference between \u2018null\u2019 and \u2018undefined\u2019?<\/strong><\/p>\n\n\n\n

Many of you still think that in JavaScript, null<\/em> and undefined<\/em> are same, but answer is:<\/p>\n\n\n\n

<\/div>\n\n\n\n

null !== undefined<\/em><\/strong><\/h3>\n\n\n\n
<\/div>\n\n\n\n

1. null<\/em><\/h1>\n\n\n\n

The value null<\/code> represents the intentional absence of any object value. It is one of JavaScript’s primitive values<\/a> and is treated as falsy<\/a> for boolean operations.<\/p><\/blockquote>\n\n\n\n

If I say null is an object? Would you believe me? Watch below gif<\/strong><\/p>\n\n\n\n

\"\"
gif demonstrating\u00a0null<\/em><\/strong>
<\/figcaption><\/figure>\n\n\n\n

It was surprising to me also, but this the wonderful JavaScript<\/strong>. We should really understand the working of JavaScript<\/strong>.<\/p>\n\n\n\n

null<\/em><\/strong>\u00a0means\u00a0empty<\/em><\/strong>\u00a0and can be\u00a0assigned<\/em><\/strong>\u00a0and which means\u00a0nothing<\/em><\/strong>.<\/p>\n\n\n\n

\n\n\n\n
<\/div>\n\n\n\n

2. undefined<\/em><\/strong><\/h1>\n\n\n\n

The global undefined<\/strong><\/code> property represents the primitive value undefined<\/a><\/code>. It is one of JavaScript’s primitive types<\/a>.<\/p><\/blockquote>\n\n\n\n

No..no..no<\/em><\/strong>, what you are thinking is not like that ?\u00a0undefined<\/em><\/strong>\u00a0is not an object like\u00a0null<\/em><\/strong><\/p>\n\n\n\n

\"\"
gif demonstrating\u00a0undefined<\/em><\/strong>
<\/figcaption><\/figure>\n\n\n\n

undefined<\/em><\/strong>\u00a0means a variable which was declared but not yet been assigned any value.<\/p>\n\n\n\n

\"\"
example for\u00a0undefined<\/em><\/strong>
<\/figcaption><\/figure>\n\n\n\n

undefined<\/em><\/strong> is of type undefined<\/em><\/strong><\/a><\/p>\n\n\n\n

Conclusion<\/h1>\n\n\n\n

Summary:<\/em><\/strong><\/p>

undefined<\/em><\/strong> is something which is not defined and is of undefined<\/em><\/strong> type<\/p>

null<\/em><\/strong> is empty and having no value and is of object<\/em><\/strong> type<\/p><\/blockquote>\n\n\n\n

There are many thing which is still to explore by us in JavaScript. JavaScript really very deep and powerful. Invest your time to learn JavaScript by considering example for each concept you learn.<\/p>\n","protected":false},"excerpt":{"rendered":"

Difference between \u2018null\u2019 and \u2018undefined\u2019? Many of you still think that in JavaScript, null and undefined are same, but answer is: null !== undefined 1. null The value null represents the intentional absence of any object value. It is one of JavaScript’s primitive values and is treated as falsy for boolean operations. If I say null is an object? Would you believe me? Watch below […]<\/p>\n","protected":false},"author":1,"featured_media":68,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[22,4,10],"tags":[9,27,28],"class_list":["post-67","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","category-javascript","category-ngpune","tag-javascript","tag-null","tag-undefined"],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/codecasm.com\/blogs\/wp-content\/uploads\/2021\/01\/maxresdefault.jpg?fit=1280%2C720&ssl=1","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/posts\/67","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/comments?post=67"}],"version-history":[{"count":7,"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/posts\/67\/revisions"}],"predecessor-version":[{"id":78,"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/posts\/67\/revisions\/78"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/media\/68"}],"wp:attachment":[{"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/media?parent=67"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/categories?post=67"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/codecasm.com\/blogs\/wp-json\/wp\/v2\/tags?post=67"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}