{"id":48,"date":"2021-03-07T15:27:45","date_gmt":"2021-03-07T15:27:45","guid":{"rendered":"https:\/\/phptutorial.net\/?page_id=48"},"modified":"2025-04-05T14:18:46","modified_gmt":"2025-04-05T14:18:46","slug":"php-boolean","status":"publish","type":"page","link":"https:\/\/www.phptutorial.net\/php-tutorial\/php-boolean\/","title":{"rendered":"PHP Boolean"},"content":{"rendered":"\n<p><strong>Summary<\/strong>: in this tutorial, you&#8217;ll learn about the PHP Boolean data type and the boolean values<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id='introduction-to-php-boolean'>Introduction to PHP Boolean <a href=\"#introduction-to-php-boolean\" class=\"anchor\" id=\"introduction-to-php-boolean\" title=\"Anchor for Introduction to PHP Boolean\">#<\/a><\/h2>\n\n\n\n<p>A boolean value represents a truth value. In other words, a boolean value can be either <code>true<\/code> or <code>false<\/code>. PHP uses the <code>bool<\/code> type to represent boolean values.<\/p>\n\n\n\n<p>To represent boolean literals, you can use the <code>true<\/code> and <code>false<\/code> keywords. These keywords are case-insensitive. Therefore, the following are the same as <code>true<\/code>:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>True<\/code><\/li>\n\n\n\n<li><code>TRUE<\/code><\/li>\n<\/ul>\n\n\n\n<p>And the following are the same as <code>false<\/code>:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><span style=\"background-color: inherit; font-family: monospace; font-size: inherit;\"><code>False<\/code><\/span><\/li>\n\n\n\n<li><code>FALSE<\/code><\/li>\n<\/ul>\n\n\n\n<p>When you use non-boolean values in a boolean context, e.g., <code><a href=\"https:\/\/phptutorial.net\/php-tutorial\/php-if\/\">if<\/a><\/code> statement. PHP evaluates that value to a boolean value. The following values evaluate to <code>false<\/code>:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The keyword <code>false<\/code><\/li>\n\n\n\n<li>The <a href=\"https:\/\/phptutorial.net\/php-tutorial\/php-int\/\">integer<\/a> zero (0)<\/li>\n\n\n\n<li>The <a href=\"https:\/\/phptutorial.net\/php-tutorial\/php-float\/\">floating-point number<\/a> zero (0.0)<\/li>\n\n\n\n<li>The empty string (<code>''<\/code>) and the string <code>\"0\"<\/code><\/li>\n\n\n\n<li>The <code>NULL<\/code> value<\/li>\n\n\n\n<li>An empty array, i.e., an array with zero elements<\/li>\n<\/ul>\n\n\n\n<p>PHP evaluates other values to <code>true<\/code>.<\/p>\n\n\n\n<p>The following shows how to declare <a href=\"https:\/\/phptutorial.net\/php-tutorial\/php-variables\/\">variables<\/a> that hold Boolean values:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-1\" data-shcb-language-name=\"PHP\" data-shcb-language-slug=\"php\"><span><code class=\"hljs language-php\"><span class=\"hljs-meta\">&lt;?php<\/span>\n\n$is_submitted = <span class=\"hljs-keyword\">false<\/span>;\n$is_valid = <span class=\"hljs-keyword\">true<\/span>;<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-1\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PHP<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">php<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p>To check if a value is a Boolean, you can use the built-in function <code>is_bool()<\/code>. For example:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-2\" data-shcb-language-name=\"PHP\" data-shcb-language-slug=\"php\"><span><code class=\"hljs language-php\"><span class=\"hljs-meta\">&lt;?php<\/span>\n\n$is_email_valid = <span class=\"hljs-keyword\">false<\/span>;\n<span class=\"hljs-keyword\">echo<\/span> is_bool($is_email_valid);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-2\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PHP<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">php<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/phptutorial.net\/playground\/?q=PD9waHAKCiRpc19lbWFpbF92YWxpZCA9IGZhbHNlOwplY2hvIGlzX2Jvb2woJGlzX2VtYWlsX3ZhbGlkKTs\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>When you use the <code>echo<\/code> to show a boolean value, it&#8217;ll show <code>1<\/code> for <code>true<\/code> and nothing for <code>false<\/code>, which is not intuitive. To make it more obvious, you can use the <code><a href=\"https:\/\/phptutorial.net\/php-tutorial\/php-var_dump\/\">var_dump()<\/a><\/code> function. For example:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-3\" data-shcb-language-name=\"PHP\" data-shcb-language-slug=\"php\"><span><code class=\"hljs language-php\"><span class=\"hljs-meta\">&lt;?php<\/span>\n\n$is_email_valid = <span class=\"hljs-keyword\">false<\/span>;\nvar_dump($is_email_valid);\n\n$is_submitted = <span class=\"hljs-keyword\">true<\/span>;\nvar_dump($is_submitted);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-3\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PHP<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">php<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><a href=\"https:\/\/phptutorial.net\/playground\/?q=PD9waHAKCiRpc19lbWFpbF92YWxpZCA9IGZhbHNlOwp2YXJfZHVtcCgkaXNfZW1haWxfdmFsaWQpOwoKJGlzX3N1Ym1pdHRlZCA9IHRydWU7CnZhcl9kdW1wKCRpc19zdWJtaXR0ZWQpOw\" target=\"_blank\" rel=\"noreferrer noopener\">Try it<\/a><\/p>\n\n\n\n<p>Output:<\/p>\n\n\n<pre class=\"wp-block-code\" aria-describedby=\"shcb-language-4\" data-shcb-language-name=\"PHP\" data-shcb-language-slug=\"php\"><span><code class=\"hljs language-php\">bool(<span class=\"hljs-keyword\">false<\/span>)\nbool(<span class=\"hljs-keyword\">true<\/span>)<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-4\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">PHP<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">php<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<h2 class=\"wp-block-heading\" id='summary'>Summary <a href=\"#summary\" class=\"anchor\" id=\"summary\" title=\"Anchor for Summary\">#<\/a><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>A boolean value represents a truth value, which is either <code>true<\/code> or <code>false<\/code>.<\/li>\n\n\n\n<li>PHP evaluates the following values to false: false, 0, 0.0, empty string (&#8220;&#8221;), &#8220;0&#8221;, NULL, an empty array; other values are <code>true<\/code>.<\/li>\n<\/ul>\n<div class=\"helpful-block-content\" data-title=\"\">\n\t<header>\n\t\t<div class=\"wth-question\">Did you find this tutorial useful?<\/div>\n\t\t<div class=\"wth-thumbs\">\n\t\t\t<button\n\t\t\t\tdata-post=\"48\"\n\t\t\t\tdata-post-url=\"https:\/\/www.phptutorial.net\/php-tutorial\/php-boolean\/\"\n\t\t\t\tdata-post-title=\"PHP Boolean\"\n\t\t\t\tdata-response=\"1\"\n\t\t\t\tclass=\"wth-btn-rounded wth-yes-btn\"\n\t\t\t>\n\t\t\t\t<svg\n\t\t\t\t\txmlns=\"http:\/\/www.w3.org\/2000\/svg\"\n\t\t\t\t\tviewBox=\"0 0 24 24\"\n\t\t\t\t\tfill=\"none\"\n\t\t\t\t\tstroke=\"currentColor\"\n\t\t\t\t\tstroke-width=\"2\"\n\t\t\t\t\tstroke-linecap=\"round\"\n\t\t\t\t\tstroke-linejoin=\"round\"\n\t\t\t\t\tclass=\"feather feather-thumbs-up block w-full h-full\"\n\t\t\t\t>\n\t\t\t\t\t<path\n\t\t\t\t\t\td=\"M14 9V5a3 3 0 0 0-3-3l-4 9v11h11.28a2 2 0 0 0 2-1.7l1.38-9a2 2 0 0 0-2-2.3zM7 22H4a2 2 0 0 1-2-2v-7a2 2 0 0 1 2-2h3\"\n\t\t\t\t\t><\/path>\n\t\t\t\t<\/svg>\n\t\t\t\t<span class=\"sr-only\"> Yes <\/span>\n\t\t\t<\/button>\n\n\t\t\t<button\n\t\t\t\tdata-response=\"0\"\n\t\t\t\tdata-post=\"48\"\n\t\t\t\tdata-post-url=\"https:\/\/www.phptutorial.net\/php-tutorial\/php-boolean\/\"\n\t\t\t\tdata-post-title=\"PHP Boolean\"\n\t\t\t\tclass=\"wth-btn-rounded wth-no-btn\"\n\t\t\t>\n\t\t\t\t<svg\n\t\t\t\t\txmlns=\"http:\/\/www.w3.org\/2000\/svg\"\n\t\t\t\t\tviewBox=\"0 0 24 24\"\n\t\t\t\t\tfill=\"none\"\n\t\t\t\t\tstroke=\"currentColor\"\n\t\t\t\t\tstroke-width=\"2\"\n\t\t\t\t\tstroke-linecap=\"round\"\n\t\t\t\t\tstroke-linejoin=\"round\"\n\t\t\t\t>\n\t\t\t\t\t<path\n\t\t\t\t\t\td=\"M10 15v4a3 3 0 0 0 3 3l4-9V2H5.72a2 2 0 0 0-2 1.7l-1.38 9a2 2 0 0 0 2 2.3zm7-13h2.67A2.31 2.31 0 0 1 22 4v7a2.31 2.31 0 0 1-2.33 2H17\"\n\t\t\t\t\t><\/path>\n\t\t\t\t<\/svg>\n\t\t\t\t<span class=\"sr-only\"> No <\/span>\n\t\t\t<\/button>\n\t\t<\/div>\n\t<\/header>\n\n\t<div class=\"wth-form hidden\">\n\t\t<div class=\"wth-form-wrapper\">\n\t\t\t<div class=\"wth-title\"><\/div>\n\t\t\t\n\t\t\t<textarea class=\"wth-message\"><\/textarea>\n\n\t\t\t<button class=\"btn btn-primary wth-btn-submit\">Send<\/button>\n\t\t\t<button class=\"btn wth-btn-cancel\">Cancel<\/button>\n\t\t\n\t\t<\/div>\n\t<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Summary: in this tutorial, you&#8217;ll learn about the PHP Boolean data type and the boolean values Introduction to PHP Boolean # A boolean value represents a truth value. In other words, a boolean value can be either true or false. PHP uses the bool type to represent boolean values. To represent boolean literals, you can [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":15,"menu_order":9,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-48","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/pages\/48","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/comments?post=48"}],"version-history":[{"count":5,"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/pages\/48\/revisions"}],"predecessor-version":[{"id":2953,"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/pages\/48\/revisions\/2953"}],"up":[{"embeddable":true,"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/pages\/15"}],"wp:attachment":[{"href":"https:\/\/www.phptutorial.net\/wp-json\/wp\/v2\/media?parent=48"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}