Map.prototype.has()
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
O método has()
retorna um booleano indicando se o elemento com a chave especificada existe ou não.
Experimente
const map1 = new Map();
map1.set("bar", "foo");
console.log(map1.has("bar"));
// Expected output: true
console.log(map1.has("baz"));
// Expected output: false
Sintaxe
js
has(key);
Parâmetros
key
-
A chave do elemento que será testado no objeto
Map
.
Valor retornado
true
se o elemento com a chave especificada existe no objeto Map
, de outra forma será retornado false
.
Exemplos
Usando has()
js
let myMap = new Map();
myMap.set("bar", "foo");
myMap.has("bar"); // retorna true
myMap.has("baz"); // retorna false
Especificações
Specification |
---|
ECMAScript® 2025 Language Specification # sec-map.prototype.has |
Compatibilidade com navegadores
Report problems with this compatibility data on GitHubdesktop | mobile | server | ||||||||||||
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has |
Legend
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- Full support
- Full support
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