I am trying to get the value of "type" from the object by iterating over it. The object looks like this.
{
"team": {
"table": [
{
"cityCode": 123,
"list": {
"players": [
{
"name": "peter",
"school": "x",
"awards": {
"type": "gold"
},
"year": 2019
}
]
}
},
{
"cityCode": 456,
"list": {
"players": [
{
"name": "Dave",
"school": "y",
"awards": {
"type": "silver"
},
"year": 2018
}
]
}
}
]
}
}
I am able to get the type values using this:
const table = team.table;
for (let i = 0; i < table.length; i++) {
const values = {
type: table[i].list.players
.filter((a) => a.awards != null)
.map((a) => a.awards.type)
.join(" "),
};
}
However, I want to use another filter on the "list" to filter non null lists. So how can I achieve that.
You want to check Check if 'list' key exists inside a team.table JSON object
you can check by
if(table[i].hasOwnProperty('list')){
}
code is
const table = team.table;
for (let i = 0; i < table.length; i++) {
if(table[i].hasOwnProperty('list')){
const values = {
type: table[i].list.players
.filter((a) => a.awards != null)
.map((a) => a.awards.type)
.join(" "),
};
}
}
1) You can get all type using flatMap and map as:
obj.team.table.flatMap((o) => o.list.players.map((o) => o.awards.type))
const obj = {
team: {
table: [
{
cityCode: 123,
list: {
players: [
{
name: "peter",
school: "x",
awards: {
type: "gold",
},
year: 2019,
},
],
},
},
{
cityCode: 456,
list: {
players: [
{
name: "Dave",
school: "y",
awards: {
type: "silver",
},
year: 2018,
},
],
},
},
],
},
};
const types = obj.team.table.flatMap((o) => o.list.players.map((o) => o.awards.type));
console.log(types);2) Using forEach and destructuring as:
const obj = {
team: {
table: [
{
cityCode: 123,
list: {
players: [
{
name: "peter",
school: "x",
awards: {
type: "gold",
},
year: 2019,
},
],
},
},
{
cityCode: 456,
list: {
players: [
{
name: "Dave",
school: "y",
awards: {
type: "silver",
},
year: 2018,
},
],
},
},
],
},
};
const table = obj.team.table;
const types = [];
for (let i = 0; i < table.length; i++) {
const { list: { players } } = table[i]
players.forEach(({ awards: { type }}) => types.push(type))
}
console.log(types);It will be cleaner to use forEach.
You will need 2 forEach due to your data structure.
But below code will:
awards is nullawards.type is nullconst data = {
"team": {
"table": [
{
"cityCode": 123,
"list": {
"players": [
{
"name": "peter",
"school": "x",
"awards": {
"type": "gold"
},
"year": 2019
}
]
}
},
{
"cityCode": 456,
"list": {
"players": [
{
"name": "Dave",
"school": "y",
"awards": {
"type": "silver"
},
"year": 2018
},
{
"name": "Dave",
"school": "y",
"awards": {
"type": "gold"
},
"year": 2016
}
]
}
},
{
"cityCode": 444,
"list": {
"players": [
{
"name": "James",
"school": "y",
"awards": {
"type": null
},
"year": 2016
}
]
}
},
{
"cityCode": 555,
"list": {
"players": [
{
"name": "Name 101",
"school": "y",
"awards": {
"type": "platinum"
},
"year": 2016
},
{
"name": "Name 102",
"school": "y",
"awards": {
"type": null
},
"year": 2016
},
{
"name": "Name 103",
"school": "y",
"awards": null,
"year": 2016
},
]
}
}
]
}
}
// Expanded your data with more items
const data1 = data.team.table;
let types = []
data1.forEach((item, index) => {
item.list.players.forEach((player) => {
const awards = player.awards;
if (awards !== null && awards.type !== null) {
types = [...types, awards.type];
}
})
})
// Get the list of types
console.log(types);
// Get unique list of types
let unique_types = [...new Set(types)]
console.log(unique_types);