I have an array of objects and I need to scroll through them and add Maria and Cristiano's battlesWon, in the end I need to display how many BattleWon each one won as shown in the example
const array = [
{
id: '147acaa3-363c-4a28-af43-fcc035a1d500',
arena: 'Philippine Arena',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
logs: [ [Object] ]
},
{
id: 'b2ef2d28-d84d-4cc9-946f-3d57b8ce05ab',
arena: 'Greensboro Coliseum',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
logs: [ [Object] ]
}
]
Expected:
{
Cristiano: 0,
Maria: 2
}
CodePudding user response：
I think one possible solution is to loop over the array using forEach and then adding the values to a results dictionary, as you can see here:
let list = [
{
id: '147acaa3-363c-4a28-af43-fcc035a1d500',
arena: 'Philippine Arena',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
logs: [[Object]]
},
{
id: 'b2ef2d28-d84d-4cc9-946f-3d57b8ce05ab',
arena: 'Greensboro Coliseum',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
logs: [[Object]]
}
]
let results = {
Cristiano: 0,
Maria: 0
}
list.forEach(arena => {
results[arena.firstParticipant.name] = arena.firstParticipant.battlesWon
results[arena.secondParticipant.name] = arena.secondParticipant.battlesWon
})
console.log(results)CodePudding user response：
Please use this code.
const arr = [
{
id: '147acaa3-363c-4a28-af43-fcc035a1d500',
arena: 'Philippine Arena',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
logs: [ [Object] ]
},
{
id: 'b2ef2d28-d84d-4cc9-946f-3d57b8ce05ab',
arena: 'Greensboro Coliseum',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
logs: [ [Object] ]
}
]
let result = {};
arr.forEach(val => {
['firstParticipant', 'secondParticipant'].forEach(key => {
if(result.hasOwnProperty(val[key]['name'])) {
result[val[key]['name']] = val[key]['battlesWon'];
} else {
result[val[key]['name']] = val[key]['battlesWon'];
}
})
})
console.log(result);CodePudding user response：
You can do this:
const json = [
{
id: '147acaa3-363c-4a28-af43-fcc035a1d500',
arena: 'Philippine Arena',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
logs: [ [Object] ]
},
{
id: 'b2ef2d28-d84d-4cc9-946f-3d57b8ce05ab',
arena: 'Greensboro Coliseum',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
logs: [ [Object] ]
}
]
var newJson = new Array();
json.map((battle) => {
newJson[battle.firstParticipant.name] = newJson[battle.firstParticipant.name] != null ? battle.firstParticipant.battlesWon newJson[battle.firstParticipant.name] : battle.firstParticipant.battlesWon;
newJson[battle.secondParticipant.name] = newJson[battle.secondParticipant.name] != null ? battle.secondParticipant.battlesWon newJson[battle.secondParticipant.name] : battle.secondParticipant.battlesWon;
});
CodePudding user response：
You can use Array.prototype.reduce to go through each entry in your data, and then write participant data into the accumulator. The advantage is that you don't need to create a separate object outside your function.
Then, in each iteration of the reduce(), you simply use a generic function that writes participant data into the accumulator:
function handleParticipant(participant, acc) {
const { name, battlesWon } = participant;
acc[name] = (acc[name] || 0) battlesWon;
}
The real logic is in the line acc[name] = (acc[name] || 0) battlesWon, that basically says: if name is found in the dictionary, then add battlesWon to its value, otherwise you add battlesWon to a starting value of 0.
See proof-of-concept below:
const data = [
{
id: '147acaa3-363c-4a28-af43-fcc035a1d500',
arena: 'Philippine Arena',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
}
},
{
id: 'b2ef2d28-d84d-4cc9-946f-3d57b8ce05ab',
arena: 'Greensboro Coliseum',
firstParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644',
name: 'Maria',
battlesWon: 1
},
secondParticipant: {
address: '0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661',
name: 'Cristiano',
battlesWon: 0
}
}
];
function handleParticipant(participant, acc) {
const { name, battlesWon } = participant;
acc[name] = (acc[name] || 0) battlesWon;
}
const battlesWonByName = data.reduce((acc, cur) => {
const { firstParticipant, secondParticipant } = cur;
handleParticipant(firstParticipant, acc);
handleParticipant(secondParticipant, acc);
return acc;
}, {});
console.log(battlesWonByName);CodePudding user response：
You can easily achieve the result using reduce
arr.reduce((acc, curr) => {
const { firstParticipant: { name: a, battlesWon: m }, secondParticipant: { name: b, battlesWon: n } } = curr;
acc[a] = (acc[a] ?? 0) m
acc[b] = (acc[b] ?? 0) n
return acc;
}, {});
1)
const arr = [
{
id: "147acaa3-363c-4a28-af43-fcc035a1d500",
arena: "Philippine Arena",
firstParticipant: {
address: "0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661",
name: "Cristiano",
battlesWon: 0,
},
secondParticipant: {
address: "0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644",
name: "Maria",
battlesWon: 1,
},
logs: [[Object]],
},
{
id: "b2ef2d28-d84d-4cc9-946f-3d57b8ce05ab",
arena: "Greensboro Coliseum",
firstParticipant: {
address: "0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644",
name: "Maria",
battlesWon: 1,
},
secondParticipant: {
address: "0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661",
name: "Cristiano",
battlesWon: 0,
},
logs: [[Object]],
},
];
const result = arr.reduce((acc, curr) => {
const {
firstParticipant: { name: name1, battlesWon: battlesWon1 },
secondParticipant: { name: name2, battlesWon: battlesWon2 },
} = curr;
acc[name1] ? (acc[name1] = battlesWon1) : (acc[name1] = battlesWon1);
acc[name2] ? (acc[name2] = battlesWon2) : (acc[name2] = battlesWon2);
return acc;
}, {});
console.log(result);2)
const arr = [
{
id: "147acaa3-363c-4a28-af43-fcc035a1d500",
arena: "Philippine Arena",
firstParticipant: {
address: "0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661",
name: "Cristiano",
battlesWon: 0,
},
secondParticipant: {
address: "0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644",
name: "Maria",
battlesWon: 1,
},
logs: [[Object]],
},
{
id: "b2ef2d28-d84d-4cc9-946f-3d57b8ce05ab",
arena: "Greensboro Coliseum",
firstParticipant: {
address: "0x3ba59bcc1a02cb46e7de35fb0bacc860bf075644",
name: "Maria",
battlesWon: 1,
},
secondParticipant: {
address: "0x3ba59bcc1a02cb46e7de35fb0bacc860bf075661",
name: "Cristiano",
battlesWon: 0,
},
logs: [[Object]],
},
];
const result = arr.reduce((acc, { firstParticipant, secondParticipant }) => {
acc[firstParticipant.name]
? (acc[firstParticipant.name] = firstParticipant.battlesWon)
: (acc[firstParticipant.name] = firstParticipant.battlesWon);
acc[secondParticipant.name]
? (acc[secondParticipant.name] = secondParticipant.battlesWon)
: (acc[secondParticipant.name] = secondParticipant.battlesWon);
return acc;
}, {});
console.log(result);