URLSearchParams: append() method

Note: This feature is available in Web Workers.

The append() method of the URLSearchParams interface appends a specified key/value pair as a new search parameter.

As shown in the example below, if the same key is appended multiple times it will appear in the parameter string multiple times for each value.

Syntax

js
append(name, value)

Parameters

name

The name of the parameter to append.

value

The value of the parameter to append.

Return value

None (undefined).

Examples

undefined

Adding the same parameter multiple times

js
const url = new URL("https://example.com?foo=1&bar=2");
const params = new URLSearchParams(url.search);

// Add a second foo parameter.
params.append("foo", 4);
// Query string is now: 'foo=1&bar=2&foo=4'

Specifications

See also