Recursion over an array of object to create custom class object - javascript

I have an javascript array of object containing some parameters to be passed to custom class.
var classObjectDetails = [{
name: "objOne",
options: ["1","2"],
children: [{
name: "childOne_objOne",
options: null
children: [{
name: "childOne_childOne_objOne",
options: ["a", "b", "c", "d"],
}]
}, {
name: "childTwo_objOne",
options: null,
}]
}, {
name: "objTwo",
options: null,
}];
Above is sample object containing details. If i have a class like below,
class sampleClass {
constructor(objName, option) {
this.name = objName;
this.options = option;
this.children = [];
// Some other properties
}
// Some other functions
}
I want to write an efficient recursive function which in the end return me the array of sampleClass object.
objOne and objTwo being two object in array, with objOne having two children and so on as given in the classObjectDetails

You can create recursive function using forEach() loop and use data from each object in original array to create instance of your class that will have all methods of that class.
var data = [{"name":"objOne","options":["1","2"],"children":[{"name":"childOne_objOne","options":null,"children":[{"name":"childOne_childOne_objOne","options":["a","b","c","d"]}]},{"name":"childTwo_objOne","options":null}]},{"name":"objTwo","options":null}]
class sampleClass {
constructor(objName, option) {
this.name = objName;
this.options = option;
this.children = [];
}
getName() {
return this.name;
}
}
function create(data) {
var result = [];
data.forEach(function(e) {
var o = new sampleClass;
o.name = e.name;
o.options = e.options
if (e.children) {
var children = create(e.children)
if (children.length) o.children = children;
}
result.push(o)
})
return result;
}
var result = create(data);
console.log(result)
console.log(result[0].children[0].getName())

<script>
var classObjectDetails = [
{
name: "objOne",
options: ["1","2"],
children: [
{
name: "childOne_objOne",
options: null,
children: [
{
name: "childOne_childOne_objOne",
options: ["a", "b", "c", "d"],
}
]
},
{
name: "childTwo_objOne",
options: null,
}
]
},
{
name: "objTwo",
options: null,
}];
function parseJSONTosampleClass(classObjectDetail){
var sampleClasList = [];
for (var key in classObjectDetail) {
var child = classObjectDetail[key];
var obj = new sampleClass();
sampleClasList.push(obj);
obj.name = child["name"];
obj.options = child["options"];
obj.children = parseJSONTosampleClass(child["children"]);
}
return sampleClasList;
}
class sampleClass {
constructor(objName, option) {
this.name = objName;
this.options = option;
this.children = [];
}
}
parseJSONTosampleClass(classObjectDetails);
</script>

Related

Merge array of arrays based sub array index as keys (NodeJS/Javascript)

How to write a code that would merge my list in the following way? Performance is important. I want to convert the following array:
"list": [
[
"marketing",
"page_sections",
"PageOne"
],
[
"marketing",
"page_sections",
"PageTwo"
],
[
"webapp",
"page",
"pageone"
],
[
"webapp",
"page",
"pagetwo"
],
To the following format:
[
{
name: "marketing",
path: "marketing/",
children: [
{
name: "page_sections",
path: "marketing/page_sections",
children: [
{
name: "pageOne",
path: "marketing/page_sections/pageOne",
children: []
},
{
name: "pageTwo",
path: "marketing/page_sections/pageTwo",
children: []
},
}
],
},
{
name: "webapp",
path: "webapp/"
children: [
{
name: "page",
path: "webapp/page/"
children: [
{
name: "pageone",
path: "webapp/page/pageone"
children: []
},
{
name: "pagetwo",
path: "webapp/page/pagetwo"
children: []
},
}
]
},
]
The first index of sub array is parent, second index is child of parent, third index is child of second index (and so on).
The shortest approach is to iterate the nested names and look for an object with the same name. If not exist, create a new object. Return the children array as new level.
This approach features Array#reduce for iterating the outer array of data and for all inner arrays.
const
data = [["marketing", "page_sections", "PageOne"], ["marketing", "page_sections", "PageTwo"], ["webapp", "page", "pageone"], ["webapp", "page", "pagetwo"]],
result = data.reduce((r, names) => {
names.reduce((level, name, i, values) => {
let temp = level.find(q => q.name === name),
path = values.slice(0, i + 1).join('/') + (i ? '' : '/');
if (!temp) level.push(temp = { name, path, children: [] });
return temp.children;
}, r);
return r;
}, []);
console.log(result);
.as-console-wrapper { max-height: 100% !important; top: 0; }
Looking at the source, and your expected result.
What I would do is loop the list, and then do another loop inside the list. Mix this with Array.find..
Eg..
const data = {list:[
["marketing","page_sections","PageOne"],
["marketing","page_sections","PageTwo"],
["webapp","page","pageone"],
["webapp","page","pagetwo"]]};
function makeTree(src) {
const root = [];
for (const s of src) {
let r = root;
let path = '';
for (const name of s) {
path += `${name}/`;
let f = r.find(k => k.name === name);
if (!f) r.push(f = {name, path, children: []});
r = f.children;
}
}
return root;
}
console.log(makeTree(data.list));
.as-console-wrapper {
min-height: 100%;
}
You can do the following,
list= [
[
"marketing",
"page_sections",
"PageOne"
],
[
"marketing",
"page_sections",
"PageTwo"
],
[
"webapp",
"page",
"pageone"
],
[
"webapp",
"page",
"pagetwo"
],
];
getChildrenItem = (arr) => {
if(arr.length === 1) {
return { name: arr[0], children: []};
} else {
return { name: arr.splice(0,1)[0], children: [getChildrenItem([...arr])]};
}
}
merge = (srcArr, newObj) => {
const {name, children} = newObj;
let index = srcArr.findIndex(item => item.name === name);
if( index> -1) {
children.forEach(item => merge(srcArr[index].children, item))
return ;
} else {
srcArr.push(newObj);
return;
}
}
allObj = [];
list.forEach(item => {
let tempObj = getChildrenItem([...item]);
merge(allObj, tempObj);
});
console.log(allObj);
If Performance is an issue, I think this is one of the best solutions.
let list = [
["marketing", "page_sections", "PageOne"],
["marketing", "page_sections", "PageTwo"],
["webapp", "page", "pageone"],
["webapp", "page", "pagetwo"],
];
const dt = {};
const pushToOBJ = (Object, name) => {
if (Object[name]) return Object[name];
Object[name] = {
name,
children: {},
};
return Object[name];
};
for (let i = 0; i < list.length; i++) {
let subArray = list[i];
let st = pushToOBJ(dt, subArray[0]);
for (let j = 1; j < subArray.length; j++) {
st = pushToOBJ(st.children, subArray[j]);
}
}
let result = [];
const convertObjToChildArray = (obj) => {
if (obj === {}) return [];
let arr = Object.values(obj);
for (let i = 0; i < arr.length; i++) {
arr[i].children = convertObjToChildArray(arr[i].children);
}
return arr;
};
result = convertObjToChildArray(dt);
console.log(result);
No Use of JS find function, which already has O(n) Complexity.

Function variables as object field selector

I have the following function:
populateClinicRoomSelect(object) {
var selectArray = [];
var options = [];
for(var key in object) {
if(object.hasOwnProperty(key)) {
options = {
value: object[key].id,
label: object[key].RoomName,
};
selectArray = selectArray.concat(options);
}
}
return selectArray;
}
The idea is that takes two defined fields from the object array and places it in a new array. It works fine. I also have a few more functions exactly the same to this except the 'id' field and 'RoomName' field are different field names. Is there any way to pass 'id' and 'RoomName' as function variables to define them in the function?
Sure, you can pass field names as arguments and use [arg] accessors as you already do with [key]:
function populateClinicRoomSelect(object, valueField, labelField) {
var selectArray = [];
var options = [];
for(var key in object) {
if(object.hasOwnProperty(key)) {
options = {
value: object[key][valueField],
label: object[key][labelField],
};
selectArray = selectArray.concat(options);
}
}
return selectArray;
}
const object = {
a: {
id: 1,
room: 'first room'
},
b: {
id: 2,
room: 'second room'
}
}
const result = populateClinicRoomSelect(object, 'id', 'room');
console.log(result)
You mean like this?
function populateClinicRoomSelect(object, value, label) {
value = value || "id"; // defaults value to id
label = label || "RoomName"; // defaults label to RoomName
var selectArray = [];
var options = [];
for(var key in object) {
if(object.hasOwnProperty(key)) {
options = {
value: object[key][value],
label: object[key][label],
};
selectArray = selectArray.concat(options);
}
}
return selectArray;
}
let obj = { 1: { id:1, RoomName: "Blue Lounge" }, 2: { id:2, RoomName: "Red Lounge" } }
console.log(populateClinicRoomSelect(obj, 'id', 'RoomName'));

Filter a dom object of input tags

I am building an object from a form that is currently rendered server side. I collect all the check boxes displayed in the image below and I am trying to sort them in a way that all the check boxes under each step (1, 2, 3 etc) is a single object based on the property parentNode.
Currently the document.querySelectorAll('.checkboxes') fetches all the checkboxes in following format.
var newObj = [
{
name: 'one',
parentNode: {
id: 'stepOne'
}
},
{
name: 'two',
parentNode: {
id: 'stepTwo'
}
},
{
name: 'three',
parentNode: {
id: 'stepOne'
}
},
]
The new object should be:
var newObj = {
stepOne: [
{
name: 'one',
parentNode: {
id: 'stepOne'
}
},
{
name: 'three',
parentNode: {
id: 'stepOne'
}
},
],
stepTwo: [
{
name: 'two',
parentNode: {
id: 'stepTwo'
}
},
]
}
Usually I do something like this:
let stepOne = function(step) {
return step.parentNode.getAttribute('id') === 'stepOne';
}
let stepTwo = function(step) {
return step.parentNode.getAttribute('id') === 'stepTwo';
}
let allTheStepOnes = fetchCheckBoxes.filter(stepOne);
But filter doesn't work on dom object and this seems inefficient as well.
Proper way of doing this is a forEach loop and using associative arrays like this:
let newObject = {};
originalObject.forEach((item)=>{
let step = item.parentNode.id
if (newObj[step] === undefined) {
newObj[step] = []
}
newObj[step].push(item)
})
Using reduce we can reduce your current array into the new structure.
return newObj.reduce(function(acc, item) {
If acc[item.parentNode.id] has been defined before, retrieve this. Otherwise set it to an empty array:
acc[item.parentNode.id] = (acc[item.parentNode.id] || [])
Add the item to the array and then return it:
acc[item.parentNode.id].push(item);
return acc;
We set the accumulator as {} to start with.
Snippet to show the workings.
var newObj = [{
name: 'one',
parentNode: {
id: 'stepOne'
}
}, {
name: 'two',
parentNode: {
id: 'stepTwo'
}
}, {
name: 'three',
parentNode: {
id: 'stepOne'
}
}, ];
var newOrder = function(prevList) {
return prevList.reduce(function(acc, item) {
acc[item.parentNode.id] = (acc[item.parentNode.id] || [])
acc[item.parentNode.id].push(item);
return acc;
}, {});
}
console.log(newOrder(newObj));
This function should do the trick
function mapObj(obj) {
var result = {};
for(var i = 0; i < obj.length; i++) {
var e = obj[i];
result[e.parentNode.id] = result[e.parentNode.id] || [];
result[e.parentNode.id].push(e);
}
return result;
}

Recreate an array of nested objects recursively

I have an array of nested objects created by a user. I need to recursively check the array for if checked is set to true and recreate the nested array of objects as shown below.
With my original attempt I was able to recursively get through the nested array. However, every time it recursed I would overwrite my previous information.
$scope.newPropertyTemplate = [];
function checkProps (item, props){
debugger
var obj = {};
var arr = [];
for(var i in props){
if(props[i].checked === true){
obj.property = item;
arr.push(props[i].name);
obj.subProperties = arr;
}
if(props[i].properties){
checkProps(props[i].name, props[i].properties);
}
}
return obj;
}
for(var i = 0; i < $scope.propertyTemplate.length; i++){
if($scope.propertyTemplate[i].properties !== null){
$scope.newPropertyTemplate.push(checkProps($scope.propertyTemplate[i].name, $scope.propertyTemplate[i].properties));
// $scope.newPropertyTemplate.push( newItem.property = $scope.propertyTemplate[i].name );
}
else {
$scope.newPropertyTemplate.push($scope.propertyTemplate[i].name);
}
}
Here's an example of the nested array:
[
{name: "allocation",
properties:[
{
name: "oid",
checked: true,
properties: null,
type: "integer"
},
{
name: "person",
checked: false,
properties: [
{
name: "Expires",
checked: true,
properties: null,
type: "timestamp"
},
{
name: "State/Province",
checked: true,
properties: null,
type: "string"
}
]
],
type: "allocation"
]
Here's an example of the converted array of objects:
[
{property: "allocation",
subProperties: [
"oid",
{property: "person",
subProperties: [
"Expires",
"State/Province"
]
}
]
}
]
This should work. The returned obj from your recursive checkProps function was not being stored.
var data = [{
name: "allocation",
properties: [{
name: "oid",
checked: true,
properties: null,
type: "integer"
}, {
name: "person",
checked: false,
properties: [{
name: "Expires",
checked: true,
properties: null,
type: "timestamp"
}, {
name: "State/Province",
checked: true,
properties: null,
type: "string"
}]
},
],
type: "allocation"
}];
function process(paths) {
var arr = [];
data.forEach(function(template) {
var resultObj = {};
recurse(template, resultObj);
arr.push(resultObj);
});
console.log(arr);
}
function recurse(template, obj) {
obj.property = template.name;
if (template.properties == null)
return;
obj.subProperties = [];
template.properties.forEach(function(prop) {
var res = {};
if (prop.properties != null)
recurse(prop, res);
else if (prop.checked)
res = prop.name;
if (res)
obj.subProperties.push(res);
});;
}
process(data);

How to find a node in a tree with JavaScript

I have and object literal that is essentially a tree that does not have a fixed number of levels. How can I go about searching the tree for a particualy node and then return that node when found in an effcient manner in javascript?
Essentially I have a tree like this and would like to find the node with the title 'randomNode_1'
var data = [
{
title: 'topNode',
children: [
{
title: 'node1',
children: [
{
title: 'randomNode_1'
},
{
title: 'node2',
children: [
{
title: 'randomNode_2',
children:[
{
title: 'node2',
children: [
{
title: 'randomNode_3',
}]
}
]
}]
}]
}
]
}];
Basing this answer off of #Ravindra's answer, but with true recursion.
function searchTree(element, matchingTitle){
if(element.title == matchingTitle){
return element;
}else if (element.children != null){
var i;
var result = null;
for(i=0; result == null && i < element.children.length; i++){
result = searchTree(element.children[i], matchingTitle);
}
return result;
}
return null;
}
Then you could call it:
var element = data[0];
var result = searchTree(element, 'randomNode_1');
Here's an iterative solution:
var stack = [], node, ii;
stack.push(root);
while (stack.length > 0) {
node = stack.pop();
if (node.title == 'randomNode_1') {
// Found it!
return node;
} else if (node.children && node.children.length) {
for (ii = 0; ii < node.children.length; ii += 1) {
stack.push(node.children[ii]);
}
}
}
// Didn't find it. Return null.
return null;
Here's an iterative function using the Stack approach, inspired by FishBasketGordo's answer but taking advantage of some ES2015 syntax to shorten things.
Since this question has already been viewed a lot of times, I've decided to update my answer to also provide a function with arguments that makes it more flexible:
function search (tree, value, key = 'id', reverse = false) {
const stack = [ tree[0] ]
while (stack.length) {
const node = stack[reverse ? 'pop' : 'shift']()
if (node[key] === value) return node
node.children && stack.push(...node.children)
}
return null
}
This way, it's now possible to pass the data tree itself, the desired value to search and also the property key which can have the desired value:
search(data, 'randomNode_2', 'title')
Finally, my original answer used Array.pop which lead to matching the last item in case of multiple matches. In fact, something that could be really confusing. Inspired by Superole comment, I've made it use Array.shift now, so the first in first out behavior is the default.
If you really want the old last in first out behavior, I've provided an additional arg reverse:
search(data, 'randomNode_2', 'title', true)
My answer is inspired from FishBasketGordo's iterativ answer. It's a little bit more complex but also much more flexible and you can have more than just one root node.
/**searchs through all arrays of the tree if the for a value from a property
* #param aTree : the tree array
* #param fCompair : This function will receive each node. It's upon you to define which
condition is necessary for the match. It must return true if the condition is matched. Example:
function(oNode){ if(oNode["Name"] === "AA") return true; }
* #param bGreedy? : us true to do not stop after the first match, default is false
* #return an array with references to the nodes for which fCompair was true; In case no node was found an empty array
* will be returned
*/
var _searchTree = function(aTree, fCompair, bGreedy){
var aInnerTree = []; // will contain the inner children
var oNode; // always the current node
var aReturnNodes = []; // the nodes array which will returned
// 1. loop through all root nodes so we don't touch the tree structure
for(keysTree in aTree) {
aInnerTree.push(aTree[keysTree]);
}
while(aInnerTree.length > 0) {
oNode = aInnerTree.pop();
// check current node
if( fCompair(oNode) ){
aReturnNodes.push(oNode);
if(!bGreedy){
return aReturnNodes;
}
} else { // if (node.children && node.children.length) {
// find other objects, 1. check all properties of the node if they are arrays
for(keysNode in oNode){
// true if the property is an array
if(oNode[keysNode] instanceof Array){
// 2. push all array object to aInnerTree to search in those later
for (var i = 0; i < oNode[keysNode].length; i++) {
aInnerTree.push(oNode[keysNode][i]);
}
}
}
}
}
return aReturnNodes; // someone was greedy
}
Finally you can use the function like this:
var foundNodes = _searchTree(data, function(oNode){ if(oNode["title"] === "randomNode_3") return true; }, false);
console.log("Node with title found: ");
console.log(foundNodes[0]);
And if you want to find all nodes with this title you can simply switch the bGreedy parameter:
var foundNodes = _searchTree(data, function(oNode){ if(oNode["title"] === "randomNode_3") return true; }, true);
console.log("NodeS with title found: ");
console.log(foundNodes);
FIND A NODE IN A TREE :
let say we have a tree like
let tree = [{
id: 1,
name: 'parent',
children: [
{
id: 2,
name: 'child_1'
},
{
id: 3,
name: 'child_2',
children: [
{
id: '4',
name: 'child_2_1',
children: []
},
{
id: '5',
name: 'child_2_2',
children: []
}
]
}
]
}];
function findNodeById(tree, id) {
let result = null
if (tree.id === id) {
return tree;
}
if (Array.isArray(tree.children) && tree.children.length > 0) {
tree.children.some((node) => {
result = findNodeById(node, id);
return result;
});
}
return result;}
You have to use recursion.
var currChild = data[0];
function searchTree(currChild, searchString){
if(currChild.title == searchString){
return currChild;
}else if (currChild.children != null){
for(i=0; i < currChild.children.length; i ++){
if (currChild.children[i].title ==searchString){
return currChild.children[i];
}else{
searchTree(currChild.children[i], searchString);
}
}
return null;
}
return null;
}
ES6+:
const deepSearch = (data, value, key = 'title', sub = 'children', tempObj = {}) => {
if (value && data) {
data.find((node) => {
if (node[key] == value) {
tempObj.found = node;
return node;
}
return deepSearch(node[sub], value, key, sub, tempObj);
});
if (tempObj.found) {
return tempObj.found;
}
}
return false;
};
const result = deepSearch(data, 'randomNode_1', 'title', 'children');
This function is universal and does search recursively.
It does not matter, if input tree is object(single root), or array of objects (many root objects). You can configure prop name that holds children array in tree objects.
// Searches items tree for object with specified prop with value
//
// #param {object} tree nodes tree with children items in nodesProp[] table, with one (object) or many (array of objects) roots
// #param {string} propNodes name of prop that holds child nodes array
// #param {string} prop name of searched node's prop
// #param {mixed} value value of searched node's prop
// #returns {object/null} returns first object that match supplied arguments (prop: value) or null if no matching object was found
function searchTree(tree, nodesProp, prop, value) {
var i, f = null; // iterator, found node
if (Array.isArray(tree)) { // if entry object is array objects, check each object
for (i = 0; i < tree.length; i++) {
f = searchTree(tree[i], nodesProp, prop, value);
if (f) { // if found matching object, return it.
return f;
}
}
} else if (typeof tree === 'object') { // standard tree node (one root)
if (tree[prop] !== undefined && tree[prop] === value) {
return tree; // found matching node
}
}
if (tree[nodesProp] !== undefined && tree[nodesProp].length > 0) { // if this is not maching node, search nodes, children (if prop exist and it is not empty)
return searchTree(tree[nodesProp], nodesProp, prop, value);
} else {
return null; // node does not match and it neither have children
}
}
I tested it localy and it works ok, but it somehow won't run on jsfiddle or jsbin...(recurency issues on those sites ??)
run code :
var data = [{
title: 'topNode',
children: [{
title: 'node1',
children: [{
title: 'randomNode_1'
}, {
title: 'node2',
children: [{
title: 'randomNode_2',
children: [{
title: 'node2',
children: [{
title: 'randomNode_3',
}]
}]
}]
}]
}]
}];
var r = searchTree(data, 'children', 'title', 'randomNode_1');
//var r = searchTree(data, 'children', 'title', 'node2'); // check it too
console.log(r);
It works in http://www.pythontutor.com/live.html#mode=edit (paste the code)
no BS version:
const find = (root, title) =>
root.title === title ?
root :
root.children?.reduce((result, n) => result || find(n, title), undefined)
This is basic recursion problem.
window.parser = function(searchParam, data) {
if(data.title != searchParam) {
returnData = window.parser(searchParam, children)
} else {
returnData = data;
}
return returnData;
}
here is a more complex option - it finds the first item in a tree-like node with providing (node, nodeChildrenKey, key/value pairs & optional additional key/value pairs)
const findInTree = (node, childrenKey, key, value, additionalKey?, additionalValue?) => {
let found = null;
if (additionalKey && additionalValue) {
found = node[childrenKey].find(x => x[key] === value && x[additionalKey] === additionalValue);
} else {
found = node[childrenKey].find(x => x[key] === value);
}
if (typeof(found) === 'undefined') {
for (const item of node[childrenKey]) {
if (typeof(found) === 'undefined' && item[childrenKey] && item[childrenKey].length > 0) {
found = findInTree(item, childrenKey, key, value, additionalKey, additionalValue);
}
}
}
return found;
};
export { findInTree };
Hope it helps someone.
A flexible recursive solution that will work for any tree
// predicate: (item) => boolean
// getChildren: (item) => treeNode[]
searchTree(predicate, getChildren, treeNode) {
function search(treeNode) {
if (!treeNode) {
return undefined;
}
for (let treeItem of treeNode) {
if (predicate(treeItem)) {
return treeItem;
}
const foundItem = search(getChildren(treeItem));
if (foundItem) {
return foundItem;
}
}
}
return search(treeNode);
}
find all parents of the element in the tree
let objects = [{
id: 'A',
name: 'ObjA',
children: [
{
id: 'A1',
name: 'ObjA1'
},
{
id: 'A2',
name: 'objA2',
children: [
{
id: 'A2-1',
name: 'objA2-1'
},
{
id: 'A2-2',
name: 'objA2-2'
}
]
}
]
},
{
id: 'B',
name: 'ObjB',
children: [
{
id: 'B1',
name: 'ObjB1'
}
]
}
];
let docs = [
{
object: {
id: 'A',
name: 'docA'
},
typedoc: {
id: 'TD1',
name: 'Typde Doc1'
}
},
{
object: {
id: 'A',
name: 'docA'
},
typedoc: {
id: 'TD2',
name: 'Typde Doc2'
}
},
{
object: {
id: 'A1',
name: 'docA1'
},
typedoc: {
id: 'TDx1',
name: 'Typde Doc x1'
}
},
{
object: {
id: 'A1',
name: 'docA1'
},
typedoc: {
id: 'TDx2',
name: 'Typde Doc x1'
}
},
{
object: {
id: 'A2',
name: 'docA2'
},
typedoc: {
id: 'TDx2',
name: 'Type de Doc x2'
}
},
{
object: {
id: 'A2-1',
name: 'docA2-1'
},
typedoc: {
id: 'TDx2-1',
name: 'Type de Docx2-1'
},
},
{
object: {
id: 'A2-2',
name: 'docA2-2'
},
typedoc: {
id: 'TDx2-2',
name: 'Type de Docx2-2'
},
},
{
object: {
id: 'B',
name: 'docB'
},
typedoc: {
id: 'TD1',
name: 'Typde Doc1'
}
},
{
object: {
id: 'B1',
name: 'docB1'
},
typedoc: {
id: 'TDx1',
name: 'Typde Doc x1'
}
}
];
function buildAllParents(doc, objects) {
for (let o = 0; o < objects.length; o++) {
let allParents = [];
let getAllParents = (o, eleFinded) => {
if (o.id === doc.object.id) {
doc.allParents = allParents;
eleFinded = true;
return { doc, eleFinded };
}
if (o.children) {
allParents.push(o.id);
for (let c = 0; c < o.children.length; c++) {
let { eleFinded, doc } = getAllParents(o.children[c], eleFinded);
if (eleFinded) {
return { eleFinded, doc };
} else {
continue;
}
}
}
return { eleFinded };
};
if (objects[o].id === doc.object.id) {
doc.allParents = [objects[o].id];
return doc;
} else if (objects[o].children) {
allParents.push(objects[o].id);
for (let c = 0; c < objects[o].children.length; c++) {
let eleFinded = null;`enter code here`
let res = getAllParents(objects[o].children[c], eleFinded);
if (res.eleFinded) {
return res.doc;
} else {
continue;
}
}
}
}
}
docs = docs.map(d => buildAllParents(d, objects`enter code here`))
This is an iterative breadth first search. It returns the first node that contains a child of a given name (nodeName) and a given value (nodeValue).
getParentNode(nodeName, nodeValue, rootNode) {
const queue= [ rootNode ]
while (queue.length) {
const node = queue.shift()
if (node[nodeName] === nodeValue) {
return node
} else if (node instanceof Object) {
const children = Object.values(node)
if (children.length) {
queue.push(...children)
}
}
}
return null
}
It would be used like this to solve the original question:
getParentNode('title', 'randomNode_1', data[0])
Enhancement of the code based on "Erick Petrucelli"
Remove the 'reverse' option
Add multi-root support
Add an option to control the visibility of 'children'
Typescript ready
Unit test ready
function searchTree(
tree: Record<string, any>[],
value: unknown,
key = 'value',
withChildren = false,
) {
let result = null;
if (!Array.isArray(tree)) return result;
for (let index = 0; index < tree.length; index += 1) {
const stack = [tree[index]];
while (stack.length) {
const node = stack.shift()!;
if (node[key] === value) {
result = node;
break;
}
if (node.children) {
stack.push(...node.children);
}
}
if (result) break;
}
if (withChildren !== true) {
delete result?.children;
}
return result;
}
And the tests can be found at: https://gist.github.com/aspirantzhang/a369aba7f84f26d57818ddef7d108682
Wrote another one based on my needs
condition is injected.
path of found branch is available
current path could be used in condition statement
could be used to map the tree items to another object
// if predicate returns true, the search is stopped
function traverse2(tree, predicate, path = "") {
if (predicate(tree, path)) return true;
for (const branch of tree.children ?? [])
if (traverse(branch, predicate, `${path ? path + "/" : ""}${branch.name}`))
return true;
}
example
let tree = {
name: "schools",
children: [
{
name: "farzanegan",
children: [
{
name: "classes",
children: [
{ name: "level1", children: [{ name: "A" }, { name: "B" }] },
{ name: "level2", children: [{ name: "C" }, { name: "D" }] },
],
},
],
},
{ name: "dastgheib", children: [{ name: "E" }, { name: "F" }] },
],
};
traverse(tree, (branch, path) => {
console.log("searching ", path);
if (branch.name === "C") {
console.log("found ", branch);
return true;
}
});
output
searching
searching farzanegan
searching farzanegan/classes
searching farzanegan/classes/level1
searching farzanegan/classes/level1/A
searching farzanegan/classes/level1/B
searching farzanegan/classes/level2
searching farzanegan/classes/level2/C
found { name: 'C' }
In 2022 use TypeScript and ES5
Just use basic recreation and built-in array method to loop over the array. Don't use Array.find() because this it will return the wrong node. Use Array.some() instead which allow you to break the loop.
interface iTree {
id: string;
children?: iTree[];
}
function findTreeNode(tree: iTree, id: string) {
let result: iTree | null = null;
if (tree.id === id) {
result = tree;
} else if (tree.children) {
tree.children.some((node) => {
result = findTreeNode(node, id);
return result; // break loop
});
}
return result;
}
const flattenTree = (data: any) => {
return _.reduce(
data,
(acc: any, item: any) => {
acc.push(item);
if (item.children) {
acc = acc.concat(flattenTree(item.children));
delete item.children;
}
return acc;
},
[]
);
};
An Approach to convert the nested tree into an object with depth 0.
We can convert the object in an object like this and can perform search more easily.
The following is working at my end:
function searchTree(data, value) {
if(data.title == value) {
return data;
}
if(data.children && data.children.length > 0) {
for(var i=0; i < data.children.length; i++) {
var node = traverseChildren(data.children[i], value);
if(node != null) {
return node;
}
}
}
return null;
}

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