URLSearchParams.set()

The set() method of the URLSearchParams interface sets the value associated with a given search parameter to the given value. If there were several matching values, this method deletes the others. If the search parameter doesn't exist, this method creates it.

Note: This feature is available in Web Workers

Syntax

URLSearchParams.set(name, value)

Parameters

name: The name of the parameter to set.
value: The value of the parameter to set.

Return value

Void.

Examples

Let's start with a simple example:

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

//Add a third parameter.
params.set('baz', 3);
params.toString(); // "foo=1&bar=2&baz=3"

Below is a real-life example demonstrating how to create a URL and set some search parameters.

You can copy and paste the example in a code environment like Codepen, JSFiddle, or the multi-line JavaScript interpreter in Firefox.

line #41: Comment out this line to stop dumping the search parameters to the console (debug()).
line #43: Dumps the generated object and its string representation to the console (info()).
line #44: Tries to automatically open a new window/tab with the generated URL (when uncommented).

'use strict'

function genURL(rExp, aText, bDebug=false){
  let theURL

  theURL= new URL('https://regexr.com')
  theURL.searchParams.set( 'expression', rExp.toString() )
  theURL.searchParams.set( 'tool', 'replace' )
  theURL.searchParams.set( 'input', '\u2911\u20dc' )// ⤑⃜
  theURL.searchParams.set( 'text', aText.join('\n') )
  if( bDebug ){
    // Display the key/value pairs
    for(var pair of theURL.searchParams.entries()) {
      console.debug(pair[0] + ' = \'' + pair[1] + '\'');
    }
    console.debug(theURL)
  }
  return theURL
}
var url = genURL(
  /(^\s*\/\/|\s*[^:]\/\/).*\s*$|\s*\/\*(.|\n)+?\*\/\s*$/gm  // single/multi-line comments
  // /(^\s*\/\/.*|\s*[^:]\/\/.*)/g                          // single-line comments
  ,[
    "These should work:",
    "",
    "// eslint-disable-next-line no-unused-vars",
    "lockPref( 'keyword.URL',\t\t'https://duckduckgo.com/html/?q=!+' )\t//      test",
    "/*",
    "  * bla bla    ",
    "*/",
    "",
    "/* bla bla */",
    "",
    "// bla bla ",
    "",
    "These shouldn\'t work:",
    "console.log(\"http://foo.co.uk/\")",
    "var url = \"http://regexr.com/foo.html?q=bar\"",
    "alert(\"https://mediatemple.net\")",
  ]
  , true
)
console.info( url, url.toString() )
// window.open( url, 'regex_site' )

Specifications

Specification
URL Standard # dom-urlsearchparams-set

Browser compatibility

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