Suppose I have an object with depth-N like:
food = {
'Non-Animal': {
'Plants' : {
'Vegetables': {
...
}
},
'Minerals' : {
...
}
},
'Animal': {
...
}
}
And I want to add in this object the category 'Fruits', but I have to search the object where 'Plants' are and then add it. So I don't want to do in one statement:
food['Non-Animal']['Plants']['Fruits'] = {};
Since I want to search first where it belongs.
How can I add the fruits category to the object while iterating through it? What I have so far is:
addCategory(food, category, parent);
function addCategory(obj, category, parent_name) {
for (var key in obj) {
if (key == parent_name) {
obj[key][category] = {};
}
var p = obj[key];
if (typeof p === 'object') {
addCategory(p, category, parent);
} else {
}
}
}
How can I fix this routine to do this or is there a better way to do this?
If I'm understanding you correctly, I think you'd want your function to define a variadic parameter that takes individual names of the path you wish to traverse and create if necessary.
Using .reduce() for this makes it pretty easy.
const food = {
'Non-Animal': {
'Plants': {
'Vegetables': {}
},
'Minerals': {}
},
'Animal': {}
}
console.log(addCategory(food, "Non-Animal", "Plants", "Fruits"));
console.log(addCategory(food, "Non-Animal", "Minerals", "Gold"));
function addCategory(obj, ...path) {
return path.reduce((curr, name) => {
if (!curr) return null;
if (!curr[name]) return (curr[name] = {});
return curr[name];
// More terse but perhaps less readable
// return curr ? curr[name] ? curr[name] : (curr[name]={}) : null;
}, obj);
}
console.log(JSON.stringify(food, null, 2));
Looks fine. However you might want to terminate after adding the prop:
function addCategory(obj, category, parent_name) {
for (var key in obj) {
if (key == parent_name){
return obj[key][category] = {};
}
var p = obj[key];
if (typeof p === 'object') {
if(addCategory(p, category, parent)) return true;
}
}
}
I see only one mistake: The recursive call of addCategory cannot find the parent-variable, cause it's called parent_name in your scope.
var food = {
'Non-Animal': {
'Plants' : {
'Vegetables': {
}
},
'Minerals' : {}
},
'Animal': {}
}
function addCategory(obj, category, parent_name) {
for (var key in obj) {
if (key == parent_name){
obj[key][category] = {};
}
var p = obj[key];
if (typeof p === 'object') {
addCategory(p, category, parent_name);
} else {
}
}
}
console.log(food);
addCategory(food, 'Fruits', 'Plants');
console.log(food);
You can use reduce to create function that will take key as string and object as value that you want to assign to some nested object.
var food = {"Non-Animal":{"Plants":{"Vegetables":{}},"Minerals":{}},"Animal":{}}
function add(key, value, object) {
key.split('.').reduce(function(r, e, i, arr) {
if(r[e] && i == arr.length - 1) Object.assign(r[e], value);
return r[e]
}, object)
}
add('Non-Animal.Plants', {'Fruits': {}}, food)
console.log(food)
Related
I need to convert "flat object" like this (input data):
{
'prop1': 'value.1',
'prop2-subprop1': 'value.2.1',
'prop2-subprop2': 'value.2.2',
}
to immersion object like this (output data):
{
'prop1': 'value.1',
'prop2': {
'subprop1': 'value.2.1',
'subprop2': 'value.2.2'
}
}
Of course solution have to be prepare for no-limit deep level.
My solution does not work:
var inputData = {
'prop1': 'value.1',
'prop2-subprop1': 'value.2.1',
'prop2-subprop2': 'value.2.2',
};
function getImmersionObj(input, value) {
var output = {};
if ($.type(input) === 'object') { // first start
$.each(input, function (prop, val) {
output = getImmersionObj(prop.split('-'), val);
});
} else if ($.type(input) === 'array') { // recursion start
$.each(input, function (idx, prop) {
output[prop] = output[prop] || {};
output = output[prop];
});
}
return output;
}
console.log(getImmersionObj(inputData)); // return empty object
Can you help me find the problem in my code or maybe you know another one, better algorithm for conversion like my?
You could use a function for spliting the path to the value and generate new objects for it.
function setValue(object, path, value) {
var way = path.split('-'),
last = way.pop();
way.reduce(function (o, k) {
return o[k] = o[k] || {};
}, object)[last] = value;
}
var object = { 'prop1': 'value.1', 'prop2-subprop1': 'value.2.1', 'prop2-subprop2': 'value.2.2' };
Object.keys(object).forEach(function (key) {
if (key.indexOf('-') !== -1) {
setValue(object, key, object[key]);
delete object[key];
}
});
console.log(object);
.as-console-wrapper { max-height: 100% !important; top: 0; }
var input = {
"property1": "value1",
"property2.property3": "value2",
"property2.property7": "value4",
"property4.property5.property6.property8": "value3"
}
function addProp(obj, path, pathValue) {
var pathArray = path.split('.');
pathArray.reduce(function (acc, value, index) {
if (index === pathArray.length - 1) {
acc[value] = pathValue;
return acc;
} else if (acc[value]) {
if (typeof acc[value] === "object" && index !== pathArray.length - 1) {
return acc[value];
} else {
var child = {};
acc[value] = child;
return child;
}
} else {
var child = {};
acc[value] = child;
return child;
}
}, obj);
}
var keys = Object.keys(input);
var output = {};
keys.forEach(function (k) {
addProp(output, k, input[k]);
});
console.log(output);
My problem is that a loop that is called in another for loop and should return an object does not return anything. When I set a breakpoint to the return statement the object is there but undefined in my callback function. types object is a global object that contains many objects as properties with the properties "title" and "id".
function searchObj(obj, query) {
for (var key in obj) {
var value = obj[key];
if (typeof value === 'object') {
searchObj(value, query)
}
if (value === query) {
return obj;
}
}
}
The function is called from here:
function callback(data){
var logs = [];
var results = data.d.results;
for (var i = 0; results.length; i++) {
var item = results[i];
var action = util.searchObj(types, item.ActionId);
var obj = {
'Created': item.Created,
'Text': String.format(action.title, item.Author.Title),
'Author': item.Author
}
logs.push(obj);
}
console.log(logs);
}
Try this:
function searchObj(obj, query) {
for (var key in obj) {
var value = obj[key];
if (typeof value === 'object') {
var result = searchObj(value, query);
if (result) {
return result;
}
}
if (value === query) {
return obj;
}
}
}
I'm trying to create a JavaScript function that creates an object using strings for structure and fills it from DOM data.
For example, the following strings could look like this:
some.example.here = "hello"
some.example.there = "hi"
other.example = "heyo"
Which should create this object:
{
some: {
example: {
here: "hello",
there: "hi"
},
other: {
example: "heyo
}
}
The data as said comes from DOM and is being load at the code segment labeled "read data into object". The data loads fine and the object structure is being setup fine as well, but the data is not being put into the data field.
Here's the code for the function:
function getDataFromElement(element) {
obj = {};
$(element)
.find("[data-value]")
.each(function() {
// create object node
valueObj = {};
currentValueObj = valueObj;
$.each($(this).attr("data-value").split("."), function(i, objpath) {
currentValueObj[objpath] = {};
currentValueObj = currentValueObj[objpath];
});
// read data into object
if($(this).is("[data-putvalue]") && $(this).attr("data-putvalue") != "html") {
currentValueObj = $(this).attr($(this).attr("data-putvalue"));
} else {
currentValueObj = $(this).html();
}
console.log(currentValueObj);
// combine with previous gathered data
obj = $.extend(true, {}, obj, valueObj);
});
return obj;
}
Does anyone know what to do?
I would do it like this:
var createObject = function(model, name, value) {
var nameParts = name.split("."),
currentObject = model;
for (var i in nameParts) {
var part = nameParts[i];
if (i == nameParts.length-1) {
currentObject[part] = value;
break;
}
if (typeof currentObject[part] == "undefined") {
currentObject[part] = {};
}
currentObject = currentObject[part];
}
};
And then use it like that:
var model = {};
createObject(model, "some.example.here", "hello");
createObject(model, "some.example.there", "hi");
createObject(model, "other.example", "heyo");
Probably this can suit you (adapted from another project of mine, adapt and use as needed):
NOTE the element's name is taken as key and value as the value
function fields2model( $elements, dataModel )
{
$elements.each(function( ){
var $el = $(this),
name = $el.attr('name'),
key, k, i, o, val
;
key = name;
val = $el.val() || '';
k = key.split('.'); o = dataModel;
while ( k.length )
{
i = k.shift( );
if ( k.length )
{
if ( !o.hasOwnProperty( i ) ) o[ i ] = /^\d+$/.test( k[0] ) ? [ ] : { };
o = o[ i ];
}
else
{
o[ i ] = val;
}
}
});
}
Example use:
<input name="some.example.here" value="hello" />
<input name="some.example.there" value="hi" />
var model = {};
fields2model($('input,textarea,select'), model);
The example elements above will give the below model:
model = {
some: {
example: {
here: "hello",
there: "hi"
}
};
Some functional implementation:
const value = 'hello';
'some.example.here'.split('.').reverse().reduce((reduction, segment, index) => {
const result = {};
if (index === 0) {
result[segment] = value;
} else {
result[segment] = reduction;
}
return result;
}, {})
#theFreedomBanana +1
Works for me
const magicFunction = (string, value) =>
string
.split('.')
.reverse()
.reduce((acc, cur, index) => ({ [cur]: index === 0 ? value : acc }), {});
I have a json object which looks like this:
var testJ = {"ROOT":{
dir : 'app',
files : [
'index.html',
{
dir : 'php',
files: [
'a.php',
{
dir : 'extras',
files : [
'a.js',
'b.js'
]
}
]
}
]
}};
I need to extract all the files and append into an array (index.html,a.php,a.js..etc)
For this I wrote a javascript code as follows:
var arr=[];
function scan(obj,append)
{
var k;
if (obj instanceof Object) {
for (k in obj){
if (obj.hasOwnProperty(k)){
if(k=='files')
{
scan( obj[k],1 );
}
}
}
} else {
body += 'found value : ' + obj + '<br/>';
if(append == 1)
arr.push(obj);
alert("Arr"+ arr);
};
};
scan(testJ,0);
I am not able to figure out where am I going wrong. Could some give me pointers?
var res = [];
function gather(j) {
for (var k in j) {
if (k === 'files') {
addFiles(j[k]);
} else if (typeof j[k] === 'object') {
gather(j[k]);
}
}
}
function addFiles(f) {
for (var i = 0; i < f.length; i++) {
if (typeof f[i] === "string") {
body += 'found value : ' + obj + '<br/>';
res.push(f[i]);
} else {
gather(f[i]);
}
}
}
gather(testJ);
Free tips:
instanceof is some cancerous stuff. Why does instanceof return false for some literals?
Always, always use === for comparison, not ==
I also wouldn't blindly use hasOwnProperty unless you're afraid the thing you're operating on might have a modified prototype, https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...in just for simplicity.
How about a map reduce approach?:
function mapJ(subject) {
return subject.files.map(function(item) {
if (typeof item === "string") {
return item;
} else {
return parseJ(item);
}
});
}
function reduceJ(subject) {
return subject.reduce(function(prev, cur) {
return prev.concat(cur);
}, []);
}
function parseJ(subject) {
return reduceJ(mapJ(subject));
}
var result = parseJ(testJ));
I have an object which contains an unknown number of other objects. Each (sub-)object may contain boolean values as strings and I want to change them to real boolean values. Here's an example object:
var myObj = {
my1stLevelKey1: "true",
my1stLevelKey2: "a normal string",
my1stLevelKey3: {
my2ndLevelKey1: {
my3rdLevelKey1: {
my4thLevelKey1: "true",
my4thLevelKey2: "false"
}
},
my2ndLevelKey2: {
my3rdLevelKey2: "FALSE"
}
}
}
What I want in the end is this:
var myObj = {
my1stLevelKey1: true,
my1stLevelKey2: "a normal string",
my1stLevelKey3: {
my2ndLevelKey1: {
my3rdLevelKey1: {
my4thLevelKey1: true,
my4thLevelKey2: false
}
},
my2ndLevelKey2: {
my3rdLevelKey2: false
}
}
}
Important is that the number sub-objects/levels is unknown. How can I do this effectively by either using classic JavaScript or Mootools?
Recursion is your friend
(function (obj) { // IIFE so you don't pollute your namespace
// define things you can share to save memory
var map = Object.create(null);
map['true'] = true;
map['false'] = false;
// the recursive iterator
function walker(obj) {
var k,
has = Object.prototype.hasOwnProperty.bind(obj);
for (k in obj) if (has(k)) {
switch (typeof obj[k]) {
case 'object':
walker(obj[k]); break;
case 'string':
if (obj[k].toLowerCase() in map) obj[k] = map[obj[k].toLowerCase()]
}
}
}
// set it running
walker(obj);
}(myObj));
The obj[k].toLowerCase() is to make it case-insensitive
Walk each level of the object and replace boolean string values with the appropriate booleans. If you find an object, recurse in and replace again.
You can use Object.keys to grab all the members of each object, without worrying about getting inherited properties that you shouldn't.
var myObj = {
my1stLevelKey1: "true",
my1stLevelKey2: "a normal string",
my1stLevelKey3: {
my2ndLevelKey1: {
my3rdLevelKey1: {
my4thLevelKey1: "true",
my4thLevelKey2: "false"
}
},
my2ndLevelKey2: {
my3rdLevelKey2: "FALSE"
}
}
};
function booleanizeObject(obj) {
var keys = Object.keys(obj);
keys.forEach(function(key) {
var value = obj[key];
if (typeof value === 'string') {
var lvalue = value.toLowerCase();
if (lvalue === 'true') {
obj[key] = true;
} else if (lvalue === 'false') {
obj[key] = false;
}
} else if (typeof value === 'object') {
booleanizeObject(obj[key]);
}
});
}
booleanizeObject(myObj);
document.getElementById('results').textContent = JSON.stringify(myObj);
<pre id="results"></pre>
JavaScript data structures elegantly can be sanitized by recursive functional reduce approaches.
var myObj = {
my1stLevelKey1: "true",
my1stLevelKey2: "a normal string",
my1stLevelKey3: {
my2ndLevelKey1: {
my3rdLevelKey1: {
my4thLevelKey1: "true",
my4thLevelKey2: "false"
}
},
my2ndLevelKey2: {
my3rdLevelKey2: "FALSE"
}
}
};
myObj = Object.keys(myObj).reduce(function sanitizeBooleanStructureRecursively (collector, key) {
var
source = collector.source,
target = collector.target,
value = source[key],
str
;
if (value && (typeof value == "object")) {
value = Object.keys(value).reduce(sanitizeBooleanStructureRecursively, {
source: value,
target: {}
}).target;
} else if (typeof value == "string") {
str = value.toLowerCase();
value = ((str == "true") && true) || ((str == "false") ? false : value)
}
target[key] = value;
return collector;
}, {
source: myObj,
target: {}
}).target;
console.log(myObj);
Plain javascript recursion example:
function mapDeep( obj ) {
for ( var prop in obj ) {
if ( obj[prop] === Object(obj[prop]) ) mapDeep( obj[prop] );
else if ( obj[prop].toLowerCase() === 'false' ) obj[prop] = false;
else if ( obj[prop].toLowerCase() === 'true' ) obj[prop] = true;
}
};
And MooTools example, by extending the Object type with custom mapDeep() function:
Object.extend( 'mapDeep', function( obj, custom ) {
return Object.map( obj, function( value, key ) {
if ( value === Object( value ) )
return Object.mapDeep( value, custom );
else
return custom( value, key );
});
});
myObj = Object.mapDeep( myObj, function( value, key ) {
var bool = { 'true': true, 'false': false };
return value.toLowerCase() in bool ? bool[ value.toLowerCase() ] : value;
})