Given an array like this, where the maximum depth can be 3 levels and where we don't know at what level the researched item could be:
const data = {
id: '1',
children: [
{
id: '2',
name: 'nameTest',
children: [
{
id: '3'
name: 'deepLevel'
}
]
}
}
how can I add a property to the third level knowing only the value 'deepLevel' ? we are allowed to use lodash and strongly encouraged to use ES6.
the final dataStructure should be
Given an array like this, where the maximum depth can be of 3 levels:
const data = {
id: '1',
children: [
{
id: '2',
name: 'nameTest',
children: [
{
id: '3'
name: 'deepLevel'
addedProperty: true,
}
]
}
}
An approach was to separate the tasks of finding a nested item by a custom(izable) entry (key-value pair) and assigning additional custom data to the found item.
Thus one e.g. could implement two methods recursivelyFindItemByEntry which is based on self recursion and a simple assignToObjectWithFirstMatchingNestedEntry which assigns provided data to the result of the former function invocation ...
function recursivelyFindItemByEntry(obj, [key, value]) {
let item;
if (!!obj && (typeof obj === 'object')) {
if (
obj.hasOwnProperty(key) &&
(obj[key] === value)
) {
item = obj;
} else if (
obj.hasOwnProperty('children') &&
Array.isArray(obj.children)
) {
obj.children.some(child => {
item = recursivelyFindItemByEntry(child, [key, value]);
return !!item;
});
}
}
return item;
}
function assignToObjectWithFirstMatchingNestedEntry(obj, [key, value], data) {
Object.assign(
recursivelyFindItemByEntry(obj, [key, value]) ?? {},
data ?? {}
);
return obj;
}
const data = {
id: '1',
children: [{
id: '2',
name: 'nameTest',
children: [{
id: '3',
name: 'deepLevel',
}, {
id: '4',
name: 'deepLevel',
}],
}, {
id: '5',
name: 'nameTest',
children: [{
id: '6',
name: 'deepLevel',
}, {
id: '7',
name: 'deepLevelTarget',
// addedProperty: true,
}, {
id: '8',
name: 'deepLevel',
}],
}, {
id: '9',
name: 'nameTest'
}, {
id: '10',
name: 'nameTestTarget'
}, {
id: '11',
name: 'nameTest'
}],
};
console.log(
"recursivelyFindItemByEntry(data, ['name', 'deepLevelTarget']) ...",
recursivelyFindItemByEntry(data, ['name', 'deepLevelTarget'])
);
console.log(
"recursivelyFindItemByEntry(data, ['id', '10']) ...",
recursivelyFindItemByEntry(data, ['id', '10'])
);
console.log('\n');
console.log(
"recursivelyFindItemByEntry(data, ['id', 'foo']) ...",
recursivelyFindItemByEntry(data, ['id', 'foo'])
);
console.log(
"recursivelyFindItemByEntry(data, ['id', '1']) ...",
recursivelyFindItemByEntry(data, ['id', '1'])
);
console.log('\n');
console.log(
"assignToObjectWithFirstMatchingNestedEntry(data, ['name', 'deepLevelTarget']), { addedProperty: true } ...",
assignToObjectWithFirstMatchingNestedEntry(data, ['name', 'deepLevelTarget'], { addedProperty: true })
);.as-console-wrapper { min-height: 100%!important; top: 0; }