How to get the value from the GET parameters?
JavaScript itself has nothing built in for handling query string parameters.
Code running in a (modern) browser you can use the URL object (which is part of the APIs provided by browsers to JS):
var url_string = "http://www.example.com/t.html?a=1&b=3&c=m2-m3-m4-m5"; //window.location.hrefvar url = new URL(url_string);var c = url.searchParams.get("c");console.log(c);For older browsers (including Internet Explorer), you can use this polyfill or the code from the original version of this answer that predates URL:
You could access location.search, which would give you from the ? character on to the end of the URL or the start of the fragment identifier (#foo), whichever comes first.
Then you can parse it with this:
function parse_query_string(query) { var vars = query.split("&"); var query_string = {}; for (var i = 0; i < vars.length; i++) { var pair = vars[i].split("="); var key = decodeURIComponent(pair[0]); var value = decodeURIComponent(pair[1]); // If first entry with this name if (typeof query_string[key] === "undefined") { query_string[key] = decodeURIComponent(value); // If second entry with this name } else if (typeof query_string[key] === "string") { var arr = [query_string[key], decodeURIComponent(value)]; query_string[key] = arr; // If third or later entry with this name } else { query_string[key].push(decodeURIComponent(value)); } } return query_string;}var query_string = "a=1&b=3&c=m2-m3-m4-m5";var parsed_qs = parse_query_string(query_string);console.log(parsed_qs.c);You can get the query string from the URL of the current page with:
var query = window.location.search.substring(1);var qs = parse_query_string(query);
Most implementations I've seen miss out URL-decoding the names and the values.
Here's a general utility function that also does proper URL-decoding:
function getQueryParams(qs) { qs = qs.split('+').join(' '); var params = {}, tokens, re = /[?&]?([^=]+)=([^&]*)/g; while (tokens = re.exec(qs)) { params[decodeURIComponent(tokens[1])] = decodeURIComponent(tokens[2]); } return params;}//var query = getQueryParams(document.location.search);//alert(query.foo);
function gup( name, url ) { if (!url) url = location.href; name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]"); var regexS = "[\\?&]"+name+"=([^&#]*)"; var regex = new RegExp( regexS ); var results = regex.exec( url ); return results == null ? null : results[1];}gup('q', 'hxxp://example.com/?q=abc')