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decodeURIComponent()

Baseline Widely available

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

decodeURIComponent() Uniform Resource Identifier (URI), encodeURIComponent .

In this article

function containsEncodedComponents(x) {
  // ie ?,=,&,/ etc
  return decodeURI(x) !== decodeURIComponent(x);
}

console.log(containsEncodedComponents("%3Fx%3Dtest")); // ?x=test
// Expected output: true

console.log(containsEncodedComponents("%D1%88%D0%B5%D0%BB%D0%BB%D1%8B")); // 
// Expected output: false


decodeURIComponent(encodedURI)

encodedURI

, Uniform Resource Identifier.

, Uniform Resource Identifier (URI), .

URIError (" URI").

URI .

URL

js
decodeURIComponent("JavaScript_%D1%88%D0%B5%D0%BB%D0%BB%D1%8B");
// "JavaScript_"

js
try {
  var a = decodeURIComponent("%E0%A4%A");
} catch (e) {
  console.error(e);
}

// URIError: malformed URI sequence

Specification
ECMAScript 2027 LanguageSpecification
# sec-decodeuricomponent-encodeduricomponent

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