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encodeURI()

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since 2015 7.

encodeURI() URI UTF-8 , , , . ( .)

In this article

const uri = "https://mozilla.org/?x=";
const encoded = encodeURI(uri);
console.log(encoded);
// Expected output: "https://mozilla.org/?x=%D1%88%D0%B5%D0%BB%D0%BB%D1%8B"

try {
  console.log(decodeURI(encoded));
  // Expected output: "https://mozilla.org/?x="
} catch (e) {
  // Catches a malformed URI
  console.error(e);
}

js
encodeURI(URI);

URI

URI.

URI .

encodeURI() URI ( ) . "URI " . .

http://username:password@www.example.com:80/path/to/file.php?foo=316&bar=this+has+spaces#anchor

encodeURI() URI . , URI (" ") . (RFC 2396 )

encodeURI() .

   :

    A-Z a-z 0-9 ; , / ? : @ & = + $ - _ . ! ~ * ' ( ) #

encodeURI() encodeURIComponent() .

js
var set1 = ";,/?:@&=+$#"; //  
var set2 = "-_.!~*'()"; //  
var set3 = "ABC abc 123"; //   , 

console.log(encodeURI(set1)); // ;,/?:@&=+$#
console.log(encodeURI(set2)); // -_.!~*'()
console.log(encodeURI(set3)); // ABC%20abc%20123 ( %20 )

console.log(encodeURIComponent(set1)); // %3B%2C%2F%3F%3A%40%26%3D%2B%24%23
console.log(encodeURIComponent(set2)); // -_.!~*'()
console.log(encodeURIComponent(set3)); // ABC%20abc%20123 ( %20 )

encodeURI() XMLHttpRequest , HTTP GET POST . GET POST "&", "+", "=" . encodeURIComponent() .

- URIError .

js
// high-low pair ok
console.log(encodeURIComponent("\uD800\uDFFF"));

// lone high surrogate throws "URIError: malformed URI sequence"
console.log(encodeURIComponent("\uD800"));

// lone low surrogate throws "URIError: malformed URI sequence"
console.log(encodeURIComponent("\uDFFF"));

, URL RFC RFC3986 , IPv6 encodeURI() URL . .

js
function fixedEncodeURI(str) {
  return encodeURI(str).replace(/%5B/g, "[").replace(/%5D/g, "]");
}

Specification
ECMAScript 2027 LanguageSpecification
# sec-encodeuri-uri

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