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I have array object(x) that stores json (key,value) objects. I need to make sure that x only takes json object with unique key. Below, example 'id' is the key, so i don't want to store other json objects with 'item1' key.
x = [{"id":"item1","val":"Items"},{"id":"item1","val":"Items"},{"id":"item1","val":"Items"}]
var clickId = // could be "item1", "item2"....
var found = $.inArray(clickId, x); //
if(found >=0)
{
x.splice(found,1);
}
else{
x.push(new Item(clickId, obj)); //push json object
}
would this accomplish what you're looking for? https://jsfiddle.net/gukv9arj/3/
x = [
{"id":"item1","val":"Items"},
{"id":"item1","val":"Items"},
{"id":"item2","val":"Items"}
];
var clickId = [];
var list = JSON.parse(x);
$.each(list, function(index, value){
if(clickId.indexOf(value.id) === -1){
clickId.push(value.id);
}
});
You can't use inArray() because you are searching for an object.
I'd recommend rewriting a custom find using Array.some() as follows.
var x = [{"id":"item1","val":"Items"},{"id":"item1","val":"Items"},{"id":"item1","val":"Items"}]
var clickId = "item1";
var found = x.some(function(value) {
return value.id === clickId;
});
alert(found);
Almost 6 years later i ended up in this question, but i needed to fill a bit more complex array, with objects. So i needed to add something like this.
var values = [
{value: "value1", selected: false},
{value: "value2", selected: false}
//there cannot be another object with value = "value1" within the collection.
]
So I was looking for the value data not to be repeated (in an object's array), rather than just the value in a string's array, as required in this question. This is not the first time i think in doing something like this in some JS code.
So i did the following:
let valueIndex = {};
let values = []
//I had the source data in some other and more complex array.
for (const index in assetsArray)
{
const element = assetsArray[index];
if (!valueIndex[element.value])
{
valueIndex[element.value] = true;
values.push({
value: element.value,
selected: false
});
}
}
I just use another object as an index, so the properties in an object will never be repated. This code is quite easy to read and surely is compatible with any browser. Maybe someone comes with something better. You are welcome to share!
Hopes this helps someone else.
JS objects are great tools to use for tracking unique items. If you start with an empty object, you can incrementally add keys/values. If the object already has a key for a given item, you can set it to some known value that is use used to indicate a non-unique item.
You could then loop over the object and push the unique items to an array.
var itemsObj = {};
var itemsList = [];
x = [{"id":"item1","val":"foo"},
{"id":"item2","val":"bar"},
{"id":"item1","val":"baz"},
{"id":"item1","val":"bez"}];
for (var i = 0; i < x.length; i++) {
var item = x[i];
if (itemsObj[item.id]) {
itemsObj[item.id] = "dupe";
}
else {
itemsObj[item.id] = item;
}
}
for (var myKey in itemsObj) {
if (itemsObj[myKey] !== "dupe") {
itemsList.push(itemsObj[myKey]);
}
}
console.log(itemsList);
See a working example here: https://jsbin.com/qucuso
If you want a list of items that contain only the first instance of an id, you can do this:
var itemsObj = {};
var itemsList = [];
x = [{"id":"item1","val":"foo"},
{"id":"item2","val":"bar"},
{"id":"item1","val":"baz"},
{"id":"item1","val":"bez"}];
for (var i = 0; i < x.length; i++) {
var item = x[i];
if (!itemsObj[item.id]) {
itemsObj[item.id] = item;
itemsList.push(item);
}
}
console.log(itemsList);
This is late but I did something like the following:
let MyArray = [];
MyArray._PushAndRejectDuplicate = function(el) {
if (this.indexOf(el) == -1) this.push(el)
else return;
}
MyArray._PushAndRejectDuplicate(1); // [1]
MyArray._PushAndRejectDuplicate(2); // [1,2]
MyArray._PushAndRejectDuplicate(1); // [1,2]
This is how I would do it in pure javascript.
var x = [{"id":"item1","val":"Items"},{"id":"item1","val":"Items"},{"id":"item1","val":"Items"}];
function unique(arr, comparator) {
var uniqueArr = [];
for (var i in arr) {
var found = false;
for (var j in uniqueArr) {
if (comparator instanceof Function) {
if (comparator.call(null, arr[i], uniqueArr[j])) {
found = true;
break;
}
} else {
if (arr[i] == uniqueArr[j]) {
found = true;
break;
}
}
}
if (!found) {
uniqueArr.push(arr[i]);
}
}
return uniqueArr;
};
u = unique(x, function(a,b){ return a.id == b.id; });
console.log(u);
y = [ 1,1,2,3,4,5,5,6,1];
console.log(unique(y));
Create a very readable solution with lodash.
x = _.unionBy(x, [new Item(clickId, obj)], 'id');
let x = [{id:item1,data:value},{id:item2,data:value},{id:item3,data:value}]
let newEle = {id:newItem,data:value}
let prev = x.filter(ele=>{if(ele.id!=new.id)return ele);
newArr = [...prev,newEle]
I am creating a JS object, then stringifying it and trying to loop through the key-value pairs, but it is giving weird results. Please help.
var gv_array = {};
var gv_cookie_name = "_gv";
var gv_cookie_expiry = 1;
var $inv = jQuery.noConflict();
$inv('.product-image').bind('inview', function(event, isInView) {
if (isInView) {
var a = $inv(this).data('productid');
if(jQuery.inArray(a,gv_array) === -1){
gv_array[a]=0;
}
// Converting the array into JSON to save it to cookie
var json_gv_arr = JSON.stringify(gv_array);
setCookie(gv_cookie_name,json_gv_arr,gv_cookie_expiry);
}
});
$inv(document).ready(function(){
setInterval('sendGV()',3000);
});
function sendGV(){
var gv_cookie_val = getCookie(gv_cookie_name);
gv_cookie_val = JSON.parse(gv_cookie_val);
var gv_cookie_array = new Array();
$inv.each( gv_cookie_val, function( key, value ) {
if(value == 0){
gv_cookie_array.push(key);
}
});
alert(gv_cookie_array);
}
The JS Object looks like this when i try to alert it.
{"2234":0,"4563":0,"4555":0}
I need to send ids from the object whose value is 0 to insert into database and just after a receive the success msg from AJAX, i need to change the status of the ids in the object to 1.
UPDATE: Even after parsing the JSON string, it doesnt do anything.
try as like following:
var data = {"2234":0,"4563":0,"4555":0};
$.each(data,function(key,value){
console.log(key+":"+value);
})
Pure javacript:
data = {"2234":0,"4563":0,"4555":0};
keys = Object.keys(data); // ["2234", "4563", "4555"]
for(i = 0; i < keys.length; i++){
console.log(data[keys[i]]); // 0, 0, 0
}
and for set the values:
for(i = 0; i < keys.length; i++){
data[keys[i]] = 1
}
console.log(data); // Object { 2234=1, 4563=1, 4555=1}
Say, I have a function F1 that will be called in many other function. F1 is meant to return a value VAL that will be used in F2. A promise is needed to retrieve that needed data that will help calculate VAL. Having F1 as a promise would cause a lot of confusion in F2, for F1 is often called inside IF statements and FOR loops. Let me illustrate this scenario:
function F1(param1, param2) {
var VAL = 0;
promise(param1, param2).then(function(data) {
for (var i = 0; i < data.length; i++) {
// Do some calculation here
}
});
return VAL;
}
function F2(x1, x2) {
var myArray = [],
someValue = 0;
if ([conditional expression]) {
someValue = F1(x1, x2);
call_some_function();
myArray.push({
val: someValue,
...
});
}
var x = someValue + y;
myArray.push({
id: x,
...
});
return myArray;
}
How do I make sure that F1 returns VAL (integer) so I can use it as a synchronous function?
Thanks in advance for your help.
EDIT:
Here is how the code looks like:
function myFunc(x, y) {
return init()
.then(function() {
return getData(x, y).then(function(data) {
if (data.length == 0) return [];
var id, name,
firstPass = true,
headIn = 0,
headOut = 0,
currentHead = 0,
payWtIn = 0,
payWtOut = 0,
expectedAdg = 0,
weight = 0,
results = [];
for (var i = 0; i < data.length; i++) {
if (firstPass) {
id = data[i].id();
name = data[i].name();
headIn = data[i].headIn();
headOut = data[i].headOut();
expectedAdg = data[i].expectedAdg();
firstPass = false;
}
if (id != data[i].id()) {
buildFunc();
reset();
}
headIn += data[i].headIn();
headOut += data[i].headOut();
payWtIn += data[i].payWtIn();
payWtOut += data[i].payWtOut();
}
buildFunc();
return results;
function buildFunc() {
currentHead = headIn - headOut;
var headDays = getHeadDays({ locationId: locationId, groupId: groupId, callDate: null });
var totalWeight = headIn != 0
? ((((headDays * expectedAdg) + payWtIn) / headIn) * currentHead) + payWtOut
: 0;
results.push({
id: id,
name: name,
headIn: headIn,
headOut: headOut,
headDays: headDays,
currentHd: currentHead,
totalWt: totalWeight
});
}
function reset() {
id = data[i].id();
name = data[i].name();
headIn = data[i].headIn();
headOut = data[i].headOut();
expectedAdg = data[i].expectedAdg();
payWtIn = 0;
payWtOut = 0;
weight = 0;
}
});
});
}
function getHeadDays(params) {
var VAL = 0;
promise(params.a, params.b).then(function(data) {
for (var i = 0; i < data.length; i++) {
// Make calculation to determine VAL here
}
});
return VAL;
}
The init function loads needed entities in the cache (I'm working with BreezeJs) for querying. The getData function gets raw data that are sorted by id from database, and those data are used to determine the results array. As the data are looped through, as long as the id of each record is the same, headIn, headOut, payWtIn and payWtOut are incremented by the record fields, and when the previous and current id are different, we can calculate totalWeight and push a new record to the results array with the buildFunc function. Inside that buildFunc function, we retrieve the headDays in order to calculate totalWeight. The getHeadDays function will be called in many other functions. Please, let me know if you have any questions. Thanks in advance for your help.
You can't.
If you need to return a promise, then that is because the value won't be available until some event happens, and the function will (or at least may) return before then. That's the point of promises.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Dynamic object property name
I want to dynamically generate access to an object's property.
If I try to access mydata[i].val.name I get somename.
If I try it like mydata[i] + bar[j] (where bar[j] === '.val.name') it fails.
How do I dynamically create something like this? So that I can access any property of an object using a user generated value?
Some code:
If I have an object I want to be able to iterate through its properties, gathering the ones I am interested in. Ideally I would like something like the following:
var processData = function (data, keys, values) {
var returnData = [], i, j, k;
var parsedData = JSON.parse(data);
var keys = keys || null;
var values = values || null;
var datalen = parsedData.length;
for (i = 0; i < datalen; i++) {
returnData[i] = {};
for(j = 0; j< keys.length; j++){
for(k = 0; k < values.length; k++){
returnData[i][keys[j]] = parsedData[i] + values;
}
}
}
return returnData;
};
and then use it like:
var keys = ["foo","bar"];
var values = [".val.name", ".val.date"];
processData(data, keys, values);
But this does not work and in console I see foo="[object Object].val.name" rather than the expected foo="ACME Industries".
If you want to stick to your pattern of constructing the subscript as a string with dots in it you have to roll your own lookup function, like so:
function descend(object, sub) {
var handle = object,
stack = sub.split('.'),
history = [],
peek;
while (handle[stack[0]]) {
if (peek) {
history.push(peek);
}
peek = stack.shift();
handle = handle[peek];
}
if (stack.length > 0) {
history.push(peek);
throw "Traversal error, could not descend to '" + stack.join('.') + "' from '" + history.join('.') + "'.";
}
return handle;
}
var x = {
a: {
b: {
c: 15
},
d: 4
}
};
console.log(descend(x, "a"));
console.log(descend(x, "a.b"));
console.log(descend(x, "a.b.c"));
console.log(descend(x, "a.d"));
function processData(data, keys, values) {
if (keys.length !== values.length) {
throw "Mismatched keys and value lookups";
}
var i,
len = keys.length,
gathered = {},
k,
scratch,
v;
for (i = 0; i < len; i += 1) {
k = descend(data, keys[i]);
scratch = values[i].split('.');
scratch.shift();
v = descend(k, scratch.join('.'));
gathered[keys[i]] = v;
}
return gathered;
}
var data = {
foo: {
val: {
name: "ACME Industries"
}
},
bar: {
val: {
date: (new Date())
}
}
};
var keys = ["foo","bar"];
var values = [".val.name", ".val.date"];
processData(data, keys, values);
Please note: this will not be nearly as performant as coding without this style of lookup.
If you try:
new Object() + '.john.doe'
It will concatenate as a string, so you’ll get "[object Object].john.doe".
You should create a function that can handle dynamic property names instead (and there are plenty of those). You also might want to loose the ".foo.bar" syntax as a string (unless you plan to use eval()) and work solely with arrays instead.
If I understand correctly you need to use
mydata[i]["val"]["name"]
So, I'd use something like this:
var result =getItemByValuesPath(myData[i],values);
alert(result);
function getItemByValuesPath(item, values)
{
var result = item;
var vals = values.split(".");
for(var j=0; j<values.length; j++)
{
if(result==undefined)
{
return null;
}
result = result[values[j]];
}
}
I've got a JSON response that looks like this:
{
"COLUMNS":["SETTING_NAME","SETTING_VALUE","COLOR"],
"DATA": [
["setting_1",100.0,"yellow"],
["setting_2",150.0,"red"],
["setting_3",30.0,"green"],
["setting_4",11.0,"blue"]
]
}
How do I find the 'color' for the setting 'setting_4'? Acceptable solutions would either be am easy way to access the data, or a function to transform this into an exploded key/value array like
[
setting_1_value: '100',
setting_1_color: 'yellow',
setting_2_value: "150"
...
]
You can use this code to put the data into the type of data structure that you asked for:
var response = {"COLUMNS":["SETTING_NAME","SETTING_VALUE","COLOR"],
"DATA":[["setting_1",100.0,"yellow"],["setting_2",150.0,"red"],
["setting_3",30.0,"green"],["setting_4",11.0,"blue"]]};
var data = response.DATA;
var columns = response.COLUMNS;
var hash = {}, item, name, i;
var cols = {};
// remember order of columns
for (i = 0; i < columns.length; i++) {
cols[columns[i]] = i;
}
// fetch data from correct column
for (i = 0; i < data.length; i++) {
item = data[i];
name = item[cols["SETTING_NAME"]];
hash[name + "_value"] = item[cols["SETTING_VALUE"]];
hash[name + "_color"] = item[cols["COLOR"]];
}
hash.num = data.length;
As you requested, this gives you a data structure like this so you can directly read any value you want:
{
"setting_1_value":100,
"setting_1_color":"yellow",
"setting_2_value":150,
"setting_2_color":"red",
"setting_3_value":30,
"setting_3_color":"green",
"setting_4_value":11,
"setting_4_color":"blue",
"num":4
}
jsFiddle here: http://jsfiddle.net/jfriend00/HZmYN/ that generated this result.
Personally, I would rather use this code to parse it into this type of data structure:
var response = {"COLUMNS":["SETTING_NAME","SETTING_VALUE","COLOR"],
"DATA":[["setting_1",100.0,"yellow"],["setting_2",150.0,"red"],
["setting_3",30.0,"green"],["setting_4",11.0,"blue"]]};
var data = response.DATA;
var columns = response.COLUMNS;
var newData = [], item, obj, i, num, match;
var cols = {};
// remember order of columns
for (i = 0; i < columns.length; i++) {
cols[columns[i]] = i;
}
for (i = 0; i < data.length; i++) {
item = data[i];
obj = {};
obj.value = item[cols["SETTING_VALUE"]];
obj.color = item[cols["COLOR"]];
obj.name = item[cols["SETTING_NAME"]];
match = obj.name.match(/\d+$/);
if (match && match.length > 0) {
obj.settingNumber = parseInt(match[0], 10);
}
newData.push(obj);
}
// now sort the array by the number in the name setting
newData.sort(function(a, b) {
return(a.settingNumber- b.settingNumber);
});
And generates this data structure:
[
{"value":100,"color":"yellow","name":"setting_1","settingNumber":1},
{"value":150,"color":"red","name":"setting_2","settingNumber":2},
{"value":30,"color":"green","name":"setting_3","settingNumber":3},
{"value":11,"color":"blue","name":"setting_4","settingNumber":4}
]
Illustrated in this jsFiddle: http://jsfiddle.net/jfriend00/A23Jd/.
The reason I prefer this structure, is you can more easily access the "n" settings as an array of objects:
newData[0].color
newData[0].value
newData[0].name
newData[1].color
....
And, it's easier to iterate through the various settings
Using $.grep will allow you to access the data without mapping them before:
var json={"COLUMNS":["SETTING_NAME","SETTING_VALUE","COLOR"],
"DATA":[["setting_1",100.0,"yellow"],
["setting_2",150.0,"red"],
["setting_3",30.0,"green"],
["setting_4",11.0,"blue"]]}
alert($.grep(json.DATA, function(item){return(item[0]=='setting_4');})[0][2])//returns 'blue'
//or using the labels provided by COLUMNS:
alert($.grep(json.DATA,
function(a){return(a[0]=='setting_4');})[0][$.inArray('COLOR',json.COLUMNS)])
You can do this with a simple for loop:
var obj = {"COLUMNS":["SETTING_NAME","SETTING_VALUE","COLOR"],
"DATA":[["setting_1",100.0,"yellow"],["setting_2",150.0,"red"],
["setting_3",30.0,"green"],["setting_4",11.0,"blue"]]};
for(var i = 0; i < obj.DATA.length; i++)
{
var row = obj.DATA[i]
if (row[0] == 'setting_4')
{
console.log(row[2]);
break;
}
}
Prints:
blue
You could simply reduce that list of DATA:
DATA.reduce(function (value, item) { if (item[0] === "setting_4") return item[2] })
You could wrap that whole thing into a function for easier use, passing in the "setting_4" part. E.g.
var getColour = function (id) {
return DATA.reduce(function (value, item) {
if (item[0] === id) return item[2]
})
}
UPDATE: you could zip the two lists together, perhaps that would make access easier?
obj['DATA'].map(function (row) {
return obj['COLUMNS'].reduce(function (memo, columnName, index) {
memo[columnName] = row[index]
return memo
}, {})
})
This will return something like the following:
[{
COLOR: "yellow",
SETTING_NAME: "setting_1",
SETTING_VALUE: 100
}]
A generic algorithm for translating the dataset into a more-easily-addressed structure.
var json = {
"COLUMNS": [
"SETTING_NAME",
"SETTING_VALUE",
"COLOR"],
"DATA": [
["setting_1",100.0,"yellow"],
["setting_2",150.0,"red"],
["setting_3",30.0,"green"],
["setting_4",11.0,"blue"]
]
};
function translateJSON(json) {
var oHash = {};
var data = json['DATA'];
var cols = json['COLUMNS'];
for(var i = 0, imax = data.length; i < imax; i++) {
var row = data[i]; // shorthand
for(var j = 1, jmax = cols.length; j < jmax; j++) {
var c = cols[j]; // shorthand
oHash[(row[0] + '_' + c.replace(/[^_]+_/, '')).toLowerCase()] = row[j];
}
}
return oHash;
}
var h = translateJSON(json);
console.log(h['setting_4_color']);
Edit: updated the code. translateJSON will transform the JSON into the data structure you described, for easier property access. If you anticipate needing to access more than one property from the same JSON payload, it will be much more efficient to do a one-time transform before data access than to use something like $.grep, and much less terse than doing the column-name cross-referencing by hand.
That said, I don't think the target data structure you asked for is necessarily the best one. Assuming you can't change the structure of the JSON payload, it would still probably be better to transform that into something like:
data = {
'setting_1': { 'value': 100.0, 'color': 'yellow' },
'setting_2': { 'value': 150.0, 'color': 'red' }
...
};