There are many questions about this, but none of them solved my problem.
I have this object:
const default_keys = {
l: 1,
t: 5,
o: 10,
r: 50,
w: 100,
y: 500,
m: 1000,
f: 5000,
a: 10000,
z: 50000,
d: 100000,
q: 1000000
};
so, among all these key:value items, I want to know which key has the value = 100 (in this case it should return "w");
is it possible?
EDIT: I tried this solution, but it didn't work because it only works with fixed key names:
const object1 = {
a: {val: "aa"},
b: {val: "bb"},
c: {val: "cc"}
};
let a = Object.values(object1).find((obj) => {
return obj.val == "bb"
});
in this case the fixed name is "val", but in my case there is no fixed name..
One way would be to iterate thru Object.entries.
const default_keys = {
l: 1,
t: 5,
o: 10,
r: 50,
w: 100,
y: 500,
m: 1000,
f: 5000,
a: 10000,
z: 50000,
d: 100000,
q: 1000000
};
function getKey(object, value){
for (const [k, v] of Object.entries(object)) {
if(v == value) return k;
}
}
console.log(getKey(default_keys, 100));Another way would be to use find.
const default_keys = {
l: 1,
t: 5,
o: 10,
r: 50,
w: 100,
y: 500,
m: 1000,
f: 5000,
a: 10000,
z: 50000,
d: 100000,
q: 1000000
};
function getKey(object, value) {
let entry = Object.entries(object).find(item => item[1] == value);
if (entry) return entry[0];
}
console.log(getKey(default_keys, 100));Using for...in:
const getKeyWithValue = (obj = {}, value) => {
let key;
for(const prop in default_keys) {
if(default_keys[prop] === value) {
key = prop;
break;
}
}
return key;
}
const default_keys = { l: 1, t: 5, o: 10, r: 50, w: 100, y: 500, m: 1000, f: 5000, a: 10000, z: 50000, d: 100000, q: 1000000 };
console.log( getKeyWithValue(default_keys, 100) );You could take an object with switched key/value pairs and get the key by taking the value as key.
const
keys = { l: 1, t: 5, o: 10, r: 50, w: 100, y: 500, m: 1000, f: 5000, a: 10000, z: 50000, d: 100000, q: 1000000 },
values = Object.fromEntries(Object.entries(keys).map(([k, v]) => [v, k]));
console.log(values[100]);