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Object.entries()
const object = {
a: "some string",
b: 42,
};
for (const [key, value] of Object.entries(object)) {
console.log(`${key}: ${value}`);
}
// :
// "a: some string"
// "b: 42"
Object.entries(obj)
2 2
Object.entries() object for...in for...in Object.entries() for...in
const obj = { foo: "bar", baz: 42 };
console.log(Object.entries(obj)); // [ ['foo', 'bar'], ['baz', 42] ]
const arrayLike = { 0: "a", 1: "b", 2: "c" };
console.log(Object.entries(arrayLike)); // [ ['0', 'a'], ['1', 'b'], ['2', 'c'] ]
const randomKeyOrder = { 100: "a", 2: "b", 7: "c" };
console.log(Object.entries(randomKeyOrder)); // [ ['2', 'b'], ['7', 'c'], ['100', 'a'] ]
// getFoo
const myObj = Object.create(
{},
{
getFoo: {
value() {
return this.foo;
},
},
},
);
myObj.foo = "bar";
console.log(Object.entries(myObj)); // [ ['foo', 'bar'] ]
//
console.log(Object.entries("foo")); // [ ['0', 'f'], ['1', 'o'], ['2', 'o'] ]
// undefined null
console.log(Object.entries(100)); // []
Map() entries Object.entries Object Map
const obj = { foo: "bar", baz: 42 };
const map = new Map(Object.entries(obj));
console.log(map); // Map(2) {"foo" => "bar", "baz" => 42}
// for...of
const obj = { a: 5, b: 7, c: 9 };
for (const [key, value] of Object.entries(obj)) {
console.log(`${key} ${value}`); // "a 5", "b 7", "c 9"
}
//
Object.entries(obj).forEach(([key, value]) => {
console.log(`${key} ${value}`); // "a 5", "b 7", "c 9"
});
| ECMAScript 2027 LanguageSpecification # sec-object.entries |
Objectassign()create()defineProperties()defineProperty()entries()freeze()fromEntries()getOwnPropertyDescriptor()getOwnPropertyDescriptors()getOwnPropertyNames()getOwnPropertySymbols()getPrototypeOf()groupBy()hasOwn()is()isExtensible()isFrozen()isSealed()keys()preventExtensions()seal()setPrototypeOf()values()Object/Function| Web Proxy Viewer | New URL | Original Page |