JavaScript *itself* has nothing built in for handling query string parameters.
Code running in a (modern) browser you can use the [`URL` object](https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams) (which is part of the APIs browsers by browsers to JS):
<!-- begin snippet: js hide: false console: true babel: false -->
<!-- language: lang-js -->
var url_string = "http://www.example.com/t.html?a=1&b=3&c=m2-m3-m4-m5"; //window.location.href
var url = new URL(url_string);
var c = url.searchParams.get("c");
console.log(c);
<!-- end snippet -->
----------
For older browsers (including Internet Explorer), you can use [this polyfill](https://github.com/WebReflection/url-search-params) 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:
<!-- begin snippet: js hide: false console: true babel: false -->
<!-- language: lang-js -->
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);
<!-- end snippet -->
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);
JavaScript *itself* has nothing built in for handling query string parameters.
Code running in a (modern) browser you can use the [`URL` object](https://developer.mozilla.org/en-US/docs/Web/API/URLSearchParams) (which is part of the APIs browsers by browsers to JS):
<!-- begin snippet: js hide: false console: true babel: false -->
<!-- language: lang-js -->
var url_string = "http://www.example.com/t.html?a=1&b=3&c=m2-m3-m4-m5"; //window.location.href
var url = new URL(url_string);
var c = url.searchParams.get("c");
console.log(c);
<!-- end snippet -->
----------
For older browsers (including Internet Explorer), you can use [this polyfill](https://github.com/WebReflection/url-search-params) 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:
<!-- begin snippet: js hide: false console: true babel: false -->
<!-- language: lang-js -->
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);
<!-- end snippet -->
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);
