Given a URL, the task is to validate it. Here we are going to declare a URL valid or Invalid by matching it with the JavaScript RegExp. We’re going to discuss a few methods.
Example 1: This example validates the URL = ‘https://www.geeksforgeeks.org’ by using Regular Expression.
html
<h1 style="color:green;"> GeeksForGeeks</h1><p id="GFG_UP" style="font-size: 15px; font-weight: bold;"></p><button onclick="gfg_Run()"> click here</button><p id="GFG_DOWN" style="color:green; font-size: 20px; font-weight: bold;"></p><script> var el_up = document.getElementById("GFG_UP"); var el_down = document.getElementById("GFG_DOWN"); var expression =/[-a-zA-Z0-9@:%_\+.~#?&//=]{2,256}\.[a-z]{2,4}\b(\/[-a-zA-Z0-9@:%_\+.~#?&//=]*)?/gi; var regex = new RegExp(expression); var url = 'www.geeksforgeeks.org'; el_up.innerHTML = "URL = '" + url + "'"; function gfg_Run() { var res = ""; if (url.match(regex)) { res = "Valid URL"; } else { res = "Invalid URL"; } el_down.innerHTML = res; }</script> |
Output:
Validate URL using regular expression
Example 2: This example validates the URL = ‘https://www.neveropenorg'(Which is wrong) by using different Regular Expression than previous one.
html
<h1 style="color:green;"> GeeksForGeeks</h1><p id="GFG_UP" style="font-size: 15px; font-weight: bold;"></p><button onclick="gfg_Run()"> click here</button><p id="GFG_DOWN" style="color:green; font-size: 20px; font-weight: bold;"></p><script> var el_up = document.getElementById("GFG_UP"); var el_down = document.getElementById("GFG_DOWN"); var expression =/(https?:\/\/(?:www\.|(?!www))[a-zA-Z0-9][a-zA-Z0-9-]+[a-zA-Z0-9]\.[^\s]{2,}|www\.[a-zA-Z0-9][a-zA-Z0-9-]+[a-zA-Z0-9]\.[^\s]{2,}|https?:\/\/(?:www\.|(?!www))[a-zA-Z0-9]+\.[^\s]{2,}|www\.[a-zA-Z0-9]+\.[^\s]{2,})/gi; var regex = new RegExp(expression); var url = 'www.geekforneveropenorg'; el_up.innerHTML = "URL = '" + url + "'"; function gfg_Run() { var res = ""; if (url.match(regex)) { res = "Valid URL"; } else { res = "Invalid URL"; } el_down.innerHTML = res; }</script> |
Output:
Validate URL using regular expression
