Develop Reference

Combine the result of two input fields with JavaScript?

I have as a result from an input form a couple of strings and I want them to convert them, so they fit as data for my ajax-request. I am looking for an easy way, but I can't get it right. Basically I want to convert/map this array:
[
{ name: "[1][apples]", value: "2" }
{ name: "[1][melons]", value: "1" }
{ name: "[2][apples]", value: "2" }
{ name: "[2][melons]", value: "4" }
{ name: "[3][apples]", value: "3" }
{ name: "[3][melons]", value: "2" }
]
into
[{"id": 1, "apples": 2, "melons": 1}, {"id": 2, "apples": 2, "melons": 4}, {...}]
Any idea? I would appreciate some hint? I could't not find an easy solution via html though.
Thanks

you can use a for loop to access each element and display them.
Refer to this link. For loop in multidimensional javascript array

Firstly, I have replaced the square brackets using a regular expression and formed a new array. After that, I have merged object having same ID using spread operator.
You can refer to the code below which solves this problem.
let array = [
{ name: "[1][apples]", value: "2" },
{ name: "[1][melons]", value: "1" },
{ name: "[2][apples]", value: "2" },
{ name: "[2][melons]", value: "4" },
{ name: "[3][apples]", value: "3" },
{ name: "[3][melons]", value: "2" }];
let newArray = [];
let result = [];
array.forEach((obj, i) => {
let nameArray = obj.name.replace(/[\[\]']+/g, ' ').trim().split(' ');
let o = {};
o['id'] = parseInt(nameArray[0]);
o[nameArray[1]] = obj.value;
newArray.push(o);
});
for(let i = 0; i< newArray.length; i++) {
for(let j = i+1; j < newArray.length; j++) {
if(newArray[i].id === newArray[j].id) {
let o = {...newArray[i], ...newArray[j]};
result.push(o);`enter code here`
}
}
}
console.log('Final result', result);

Thanks for the input. I think my question needed to be more specific:
(1) Yes, they are always in order.
(2) My names of my input-tags in html appear to be an multidimensional array. This is not the case! I tried something, but it turned out to be for php.
I found the follow workaround:
function apiAdapter() {
var arrayToCopy = $("#formsteps").serializeArray();
var copiedArray = [];
for (let i = 0; i < arrayToCopy.length; i += 2) {
var id = arrayToCopy[i].name.slice(arrayToCopy[i].name.indexOf('[') + 1, arrayToCopy[i].name.indexOf(']'));
copiedArray.push({ "id": id, "apples": arrayToCopy[i].value, "melons": arrayToCopy[i + 1].value })
}
return copiedArray;
}
As I am new to JavaScript I always look for better solutions. So thanks again for your posts.

Finding objects in a nested array along with their position

I've taken the following sample from a different question. And I am able to identify the object. But I also need to find our the position of that object. For example:
var arr = [{
Id: 1,
Categories: [{
Id: 1
},
{
Id: 2
},
]
},
{
Id: 2,
Categories: [{
Id: 100
},
{
Id: 200
},
]
}
]
If I want to find the object by the Id of the Categories, I can use the following:
var matches = [];
var needle = 100; // what to look for
arr.forEach(function(e) {
matches = matches.concat(e.Categories.filter(function(c) {
return (c.Id === needle);
}));
});
However, I also need to know the position of the object in the array. For example, if we are looking for object with Id = 100, then the above code will find the object, but how do I find that it's the second object in the main array, and the first object in the Categories array?
Thanks!

Well, if every object is unique (only in one of the categories), you can simply iterate over everything.
var arr = [{
Id: 1,
Categories: [{Id: 1},{Id: 2}]
},
{
Id: 2,
Categories: [{Id: 100},{Id: 200}]
}
];
var needle = 100;
var i = 0;
var j = 0;
arr.forEach(function(c) {
c.Categories.forEach(function(e) {
if(e.Id === needle) {
console.log("Entry is in position " + i + " of the categories and in position " + j + " in its category.");
}
j++;
});
j = 0;
i++;
});

function findInArray(needle /*object*/, haystack /*array of object*/){
let out = [];
for(let i = 0; i < haystack.lenght; i++) {
if(haystack[i].property == needle.property) {
out = {pos: i, obj: haystack[i]};
}
}
return out;
}
if you need the position and have to filter over an property of the object you can use a simple for loop. in this sample your result is an array of new object because there can be more mathches than 1 on the value of the property.
i hope it helps

Iterate over the array and set index in object where match found
var categoryGroups = [{
Id : 1,
Categories : [{
Id : 1
}, {
Id : 2
},
]
}, {
Id : 2,
Categories : [{
Id : 100
}, {
Id : 200
},
]
}
]
var filterVal = [];
var needle = 100;
for (var i = 0; i < categoryGroups.length; i++) {
var subCategory = categoryGroups[i]['Categories'];
for (var j = 0; j < subCategory.length; j++) {
if (subCategory[j]['Id'] == findId) {
filterVal.push({
catIndex : i,
subCatIndex : j,
id : needle
});
}
}
}
console.log(filterVal);

Here is solution using reduce:
var arr = [{ Id: 1, Categories: [{ Id: 1 }, { Id: 2 }, ] }, { Id: 2, Categories: [{ Id: 100 }, { Id: 200 }, ] } ]
const findPositions = (id) => arr.reduce((r,c,i) => {
let indx = c.Categories.findIndex(({Id}) => Id == id)
return indx >=0 ? {mainIndex: i, categoryIndex: indx} : r
}, {})
console.log(findPositions(100)) // {mainIndex: 1, categoryIndex: 0}
console.log(findPositions(1)) // {mainIndex: 0, categoryIndex: 0}
console.log(findPositions(200)) // {mainIndex: 1, categoryIndex: 1}
console.log(findPositions(0)) // {}

Beside the given answers with fixt depth searh, you could take an recursive approach by checking the Categories property for nested structures.
function getPath(array, target) {
var path;
array.some(({ Id, Categories = [] }) => {
var temp;
if (Id === target) {
path = [Id];
return true;
}
temp = getPath(Categories, target);
if (temp) {
path = [Id, ...temp];
return true;
}
});
return path;
}
var array = [{ Id: 1, Categories: [{ Id: 1 }, { Id: 2 },] }, { Id: 2, Categories: [{ Id: 100 }, { Id: 200 }] }];
console.log(getPath(array, 100));
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problems with for loop inside another for loop Javascript

I have problems in going through these two for loops, I need to get the same elements from the first array within the cycle, but the values ​​are being repeated. I know that they are repeated depending on the data of the second array.
I tried to make comparisons but I could not get the result I want.
var array = [
{
grouper: 1
},
{
grouper: 2
},
{
grouper: 3
},
{
grouper: 4
},
];
var array2 = [
{
value: 1,
grouper: 1,
status: 100
},
{
value: 2,
grouper: 2,
status: 100
},
{
value: 3,
grouper: 3,
status: 100
}
];
for(var i = 0; i<array.length; i++){
for(var j = 0; j<array2.length; j++){
if(array2[j].grouper == array[i].grouper){
console.log(array[i].grouper+'-'+array2[j].value);
}
}
}
This is the result I want, I need all the groupers from the first array and the values from the second array:
1-1
2-2
3-3
4-
The grouper 4, does not have value, but I need to show it.
I need the second array because I'm going to compare with the data from the second array
I do not know if I am doing the process wrong. I hope you can help me.

You could simply track if there was a match (variable shown), and if there were not any, display a "half" line:
var array = [{grouper: 1},{grouper: 2},{grouper: 3},{grouper: 4},];
var array2 = [
{value: 1, grouper: 1, status: 100},
{value: 2, grouper: 2, status: 100},
{value: 3, grouper: 3, status: 100}
];
for(var i = 0; i<array.length; i++){
var shown=false;
for(var j = 0; j<array2.length; j++){
if(array2[j].grouper == array[i].grouper){
console.log(array[i].grouper+'-'+array2[j].value);
shown=true;
}
}
if(!shown){
console.log(array[i].grouper+"-");
}
}

First of all, with the example you provided I believe you want to get back:
1,2,3
There is no 4th object inside of array2, so your conditional (array2[j].grouper == array[i].grouper will never evaluate to true.
The question here is whether you are always comparing the same indexes? In this example, you're comparing array[0] to array2[0] to see if grouper in array equals grouper in array2... that's it????
In that case you just do one loop:
for (var i = 0; i < array.length; i++) {
if (array[i].grouper == array2[i].grouper) {
console.log(array[i].grouper+'-'+array2[j].value);
}
}

#FabianSierra ... with your provided example one just needs to handle the not fulfilled if clause/condition in the most inner loop.
A more generic approach additionally might take into account changing field names (keys). Thus a function and Array.reduce / Array.find based approach provides better code reuse. An example implementation then might look similar to that ...
var array = [{ // in order.
grouper: 1
}, {
grouper: 2
}, {
grouper: 3
}, {
grouper: 4
}];
var array2 = [{ // not in the order similar to `array`.
value: 22,
grouper: 2,
status: 200
}, {
value: 33,
grouper: 3,
status: 300
}, {
value: 11,
grouper: 1,
status: 100
}];
function collectRelatedItemValuesByKeys(collector, item) {
var sourceKey = collector.sourceKey;
var targetKey = collector.targetKey;
var targetList = collector.targetList;
var resultList = collector.result;
var sourceValue = item[sourceKey];
var targetValue;
var relatedItem = targetList.find(function (targetItem) {
return (targetItem[sourceKey] === sourceValue);
});
if (typeof relatedItem !== 'undefined') {
targetValue = relatedItem[targetKey];
} else if (typeof targetValue === 'undefined') {
targetValue = ''; // `relatedItem` does not exist.
}
resultList.push([sourceValue, targetValue].join('-'));
return collector;
}
var resultList = array.reduce(collectRelatedItemValuesByKeys, {
sourceKey: 'grouper',
targetKey: 'value',
targetList: array2,
result: []
}).result;
console.log('resultList : ', resultList);
resultList = array.reduce(collectRelatedItemValuesByKeys, {
sourceKey: 'grouper',
targetKey: 'status',
targetList: array2,
result: []
}).result;
console.log('resultList : ', resultList);
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Retrieving data from JSON object

I have response JSON object which has a series array of objects like this:
{
series: [
{
name: 'a',
data: [1,2,3]
},
{
name: 'b',
data: [4,5,6]
}
]
}
What I want is to retrieve the data values corresponding to the name value.
So far I have come to this:
$scope.nameArr[i] = response.series[i].name;
which is giving me correct name array but for the corresponding data value my below code is failing
for(var i=0; i<response.series.length; i++) {
$scope.nameArr[i] = response.series[i].name;
for (var j=0; j<response.series[i].data.length; j++){
$scope.dataArr[j] = response.series[i].data[j];
}
}

You could use array.filter to get the data by name.
The for loop would also work and you don't need the nested loop for this.
I would prefer the filter because it's easier to read but the for-loop is probably a bit faster in execution time.
Please have a look at the demo below or in this fiddle.
var response = {
series: [{
name: 'a',
data: [1, 2, 3]
}, {
name: 'b',
data: [4, 5, 6]
}]
};
function getDataByName(name) {
return response.series.filter(function(item, index) {
console.log(item);
return (item.name == name);
});
}
var filtered = getDataByName('a');
console.log(filtered[0].data);
$('#result').append('with filter: ' + JSON.stringify(filtered[0].data) + '<br/>');
var item, series = [];
var queryByName = 'a';
for (var i = 0; i < response.series.length; i++) {
item = response.series[i];
if (item.name == queryByName) {
series.push(item);
}
}
$('#result').append('with for loop: ' + JSON.stringify(series[0].data));
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="result"></div>

Try this:
angular.forEach(series,function(item,index){
$scope.nameArr.push(item.name);
$scope.dataArr.push(item.data);
})

Javascript solution, just change the way you do the foreach loop to
angular.forEach(array, function(item)....etc
Here:
var x = {
series: [
{
name: 'a',
data: [1,2,3]
},
{
name: 'b',
data: [4,5,6]
}
]
}
var results = [];
x.series.forEach(function(item) {
item.data.forEach(function(subitem) {
results.push(subitem);
})
});
console.log(results)
https://jsfiddle.net/6worooos/1/

Javascript: A fast way to check if an element is in a two-dimensional array?

I have a nodes_object array, which has the structure of the following kind:
nodes_object = {
1: {
source: '001',
name: 'A',
target: '004',
name: 'B'
},
2: {
source: '003',
name: 'C',
target: '001',
name: 'A'
},
}
Then I also have an array sorted which is structured in the following way:
sorted = {
1: {
val: '001',
count: '100'
},
2: {
val: '003',
count: '80'
}
I need to create a function, which would reiterate through the nodes_object, check if BOTH the source and the target are contained in one of the sorted val parameters, and if yes, proceed further.
So far I came up with the function below, which first reiterates through the nodes_object, then reiterates through the sorted to see if any of the elements is present within it, but I'm wondering if there's a faster and a more efficient way to do that?
Thank you!
for (var i = 0; i < nodes_object.length; i++) {
var sourcein = null;
var targetin = null;
for (var j = 0; j < sorted.length; j++) {
if (sorted[j].val == nodes_object[i][0]) {
sourcein = 1;
}
if (sorted[j].val == nodes_object[i][2]) {
targetin = 1;
}
}
if ((sourcein) && (targetin)) {
// Perform the function
}
}

First of all, to create arrays you use [], not {}. So it should be:
nodes_object = [
{
source: '001',
name: 'A',
target: '004',
name: 'B'
},
{
source: '003',
name: 'C',
target: '001',
name: 'A'
},
];
and similarly for sorted.
Make an object whose keys are the val objects you want to test.
hash = {};
for (var k = 0; k < sorted.length; k++) {
hash[sorted[k]] = true;
}
Then you can use in hash to test whether something is found in sorted:
var sourcein, targetin;
for (var i = 0; i < nodes_object.length; i++) {
sourcein = nodes_object[i].source in hash;
targetin = nodes_object[i].target in hash;
if (sourcein && targetin) {
...
}
}