Note: This feature is available in Web Workers.
The size read-only property of the URLSearchParams interface indicates the total number of search parameter entries.
A number indicating the total number of search parameter entries in the URLSearchParams object.
You can get the total number of search parameter entries like so:
const searchParams = new URLSearchParams("c=4&a=2&b=3&a=1");
searchParams.size; // 4Note how the a parameter is given twice, but size returns the number of all given entries (4) and not 3. To get the amount of unique keys, you can use a Set, for example:
[...new Set(searchParams.keys())].length; // 3The size property is useful for checking whether there are any search parameters at all:
const url = new URL("https://example.com?foo=1&bar=2");
if (url.searchParams.size) {
console.log("URL has search parameters!");
}