I have a large Object containing addresses and numbers.
{
'0x2bac18ad331A3137AbEC3a029dBb3A6cC25835ea': 1,
'0x22Bf3f4EA7862739024C122aDDd2FB2981c076a7': 3,
'0x9E6E8b584F26503C84661674dCD7821099c8a51d': 1,
'0x37D74ca0F842817C6FC4Ea267cF2d49DEa0C06a8': 1,
'0xDf92913902087aD0Bfac39659B60CebE1100595a': 1
// ...
}
and I try to swap key/values and store all addresses with the same number value in an Array, thinking of something like this:
var newObj = {
"1": [addr1, addr2, addr3],
"2": [addr1, addr2, addr3],
"3": [addr1, addr2, addr3]
//...
}
I found a way to swap like this:
function swaptoArray(json){
var ret = {};
for(var key in json){
ret[json[key]] = key;
}
return ret;
}
but I am having trouble making the value-part an Array containing many addresses. I tried this, but don't understand the wrong result. Any hints?
function swaptoArray(json){
var ret = {};
var newArray = [];
for(var key in json){
ret[json[key]] = newArray.push(key);
}
return ret;
}
Result:
{ '1': 5, '3': 2 }
You need an array as result for every value as key for the result.
function group(object) {
const result = {};
for (const key in object) (result[data[key]] ??= []).push(key);
return result;
}
const data = {
'0x2bac18ad331A3137AbEC3a029dBb3A6cC25835ea': 1,
'0x22Bf3f4EA7862739024C122aDDd2FB2981c076a7': 3,
'0x9E6E8b584F26503C84661674dCD7821099c8a51d': 1,
'0x37D74ca0F842817C6FC4Ea267cF2d49DEa0C06a8': 1,
'0xDf92913902087aD0Bfac39659B60CebE1100595a': 1
}
console.log(group(data));Here's a solution using Object.entries:
const obj = {
'0x2bac18ad331A3137AbEC3a029dBb3A6cC25835ea': 1,
'0x22Bf3f4EA7862739024C122aDDd2FB2981c076a7': 3,
'0x9E6E8b584F26503C84661674dCD7821099c8a51d': 1,
'0x37D74ca0F842817C6FC4Ea267cF2d49DEa0C06a8': 1,
'0xDf92913902087aD0Bfac39659B60CebE1100595a': 1
}
const objArr = Object.entries(obj)
function getArray(key) {
let ret = []
objArr.forEach(item => {
if(item[1] === key) ret.push(item[0])
})
return ret
}
function swaptoArray(json) {
let ret = {}
for (let key in json) {
const newKey = json[key]
ret[newKey] = getArray(newKey)
}
return ret
}
console.log(swaptoArray(obj))