{"id":92,"date":"2016-11-27T14:16:07","date_gmt":"2016-11-27T12:16:07","guid":{"rendered":"http:\/\/celilsemi.erkiner.com\/blog\/?p=92"},"modified":"2020-05-22T06:37:18","modified_gmt":"2020-05-22T04:37:18","slug":"safe-usage-of-html5-storage","status":"publish","type":"post","link":"https:\/\/celilsemi.erkiner.com\/blog\/safe-usage-of-html5-storage\/","title":{"rendered":"Safe Usage Of HTML5 Storage"},"content":{"rendered":"<p>Old cookie days, before HTML5 and its useful APIs like localStorage, developers were limited to cookies as storage on client-side scripting.<\/p>\n<p>There were some advantages of cookies like being able to reach directly from some back-end solutions such as PHP and some disadvantages as well, such as storage size limitations, as low as 2mb per domain.<\/p>\n<p>HTML5 lets developers move on with different technologies and different capabilities. One of the biggest evolutions happening around HTML5 today is browser-based persistent storage solution called \u201clocalStorage\u201d.<\/p>\n<p>Unlike cookies, the storage limit is far larger (at least 5MB) and the information is never transferred to the server.<\/p>\n<p>It also comes with a high degree of uncertainty, because it is browser-based space and support can vary on different devices and browsers.<\/p>\n<p>Being sure what is possible before using these new APIs is the most important thing before full integration.<\/p>\n<h2 class=\"fusion-responsive-typography-calculated\" data-lineheight=\"60px\" data-fontsize=\"50\">How to measure HTML5 localStorage<\/h2>\n<p>First of all, checking the localStorage support is fairly simple; if the browser recognises the storage object as a function instead of undefined, it works.<code><\/code><code><br \/>\n<\/code><\/p>\n\n\n<div class=\"wp-block-codemirror-blocks-code-block code-block\"><pre class=\"CodeMirror\" data-setting=\"{&quot;showPanel&quot;:false,&quot;languageLabel&quot;:false,&quot;fullScreenButton&quot;:true,&quot;copyButton&quot;:true,&quot;mode&quot;:&quot;javascript&quot;,&quot;mime&quot;:&quot;text\/javascript&quot;,&quot;theme&quot;:&quot;material&quot;,&quot;lineNumbers&quot;:false,&quot;styleActiveLine&quot;:false,&quot;lineWrapping&quot;:true,&quot;readOnly&quot;:true,&quot;fileName&quot;:&quot;&quot;,&quot;language&quot;:&quot;JavaScript&quot;,&quot;maxHeight&quot;:&quot;400px&quot;,&quot;modeName&quot;:&quot;js&quot;}\">if (typeof(Storage) !== &quot;undefined&quot;) {\n\t\/\/ According to caniuse.com 94 percent of all browsers fall into here.\n\t\/\/ http:\/\/caniuse.com\/#search=localStorage\n} else {\n\t\/\/ Sorry! No Web Storage support..\n}<\/pre><\/div>\n\n\n\n<p>Hence, it seems like there isn\u2019t much to worry about since almost all the browsers support localStorage.<\/p>\n\n\n\n<p>Yet storage space browsers give, still varies and needs to be checked before usage to be error-free.<\/p>\n\n\n\n<p>Testing the capabilities is a bit more complex than this.<\/p>\n\n\n\n<div class=\"wp-block-codemirror-blocks-code-block code-block\"><pre class=\"CodeMirror\" data-setting=\"{&quot;showPanel&quot;:false,&quot;languageLabel&quot;:false,&quot;fullScreenButton&quot;:true,&quot;copyButton&quot;:true,&quot;mode&quot;:&quot;javascript&quot;,&quot;mime&quot;:&quot;text\/javascript&quot;,&quot;theme&quot;:&quot;material&quot;,&quot;lineNumbers&quot;:false,&quot;styleActiveLine&quot;:false,&quot;lineWrapping&quot;:true,&quot;readOnly&quot;:true,&quot;fileName&quot;:&quot;&quot;,&quot;language&quot;:&quot;JavaScript&quot;,&quot;maxHeight&quot;:&quot;400px&quot;,&quot;modeName&quot;:&quot;js&quot;}\">var b = 64; \/\/ testing block size\nvar i = 0;\nvar size = 0;\ntry {\n\t\/\/ Test up to 50 MB\n    for (var i = 0; i &lt; (1024*50); i += b) {\n    \tlocalStorage.setItem('test', new Array((i * 1024) + 1).join('d'));\n    }\n} catch (e) {\n\tlocalStorage.removeItem('test');\n\tsize = i ? i - b : 0;\n}<\/pre><\/div>\n\n\n\n<p><br>This code snippet can return max storage left with a block size error rate.<\/p>\n\n\n\n<p>The basic logic behind it is writing arbitrary data until the browser returns an error. As a result, code falls into catch and saves the last successfully stored size.<br>In conclusion, until HTML5 standards are sharp as a knife and default capabilities are certain to use, it is always better to test before use.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Old cookie days, before HTML5 and its useful APIs like localStorage, developers were limited to cookies as storage on client-side scripting. There were some advantages of cookies like being able to reach directly from some back-end solutions such as PHP and some disadvantages as well, such as storage size limitations, as low as 2mb per [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"default","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[7],"tags":[2,3,4],"class_list":["post-92","post","type-post","status-publish","format-standard","hentry","category-front-end","tag-html","tag-html5","tag-javascript"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/posts\/92","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/comments?post=92"}],"version-history":[{"count":7,"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/posts\/92\/revisions"}],"predecessor-version":[{"id":133,"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/posts\/92\/revisions\/133"}],"wp:attachment":[{"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/media?parent=92"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/categories?post=92"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/celilsemi.erkiner.com\/blog\/wp-json\/wp\/v2\/tags?post=92"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}