1.0Salgudiyhttps://salgudiy.com/en/salgudiyhttps://salgudiy.com/en/author/salgudiy/rich600338<blockquote class="wp-embedded-content" data-secret="gcDgqT9rK6"><a href="https://salgudiy.com/en/js/index-length-confusion/">When .index and .length Team Up — It Gets Confusing, Right?</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://salgudiy.com/en/js/index-length-confusion/embed/#?secret=gcDgqT9rK6" width="600" height="338" title="“When .index and .length Team Up — It Gets Confusing, Right?” — Salgudiy" data-secret="gcDgqT9rK6" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); //# sourceURL=https://salgudiy.com/wp-includes/js/wp-embed.min.js </script> https://salgudiy.com/wp-content/uploads/2026/09/index-and-length-coding-with-melon-soda.webp15361400Understanding the difference between .length and .index → Learn to clearly distinguish that .length refers to the number of characters, while .index indicates the position of each character (starting from 0). Getting familiar with how the .substring() method works → Understand the rule that the start index is included, but the end index is not.