Develop Reference

JQuery autocomplete filter to search from beginning of line- input to display label but submit value

I have an array of towns - each town has a label and a value. Then there is an HTML input which should display the town label selected and on submit send the relevant value. A JQuery script with a filter that chooses the town based on the beginning characters of the label and not the characters in the rest of the label body. I need the script to, filter as designed, but when a town is selected, the HTML id #dtags must display the label and the #dtag must submit the value via a hidden input.
I have two scripts, each one does ONE of the above successfully, but I am battling to get one script to combine both "features".
I am looking for some assistance to create a single JQuery script to achieve the above. My JQuery skills are limited and the code below is what I have managed to find through searching and adapting - credit to the originators.
Please see code below:-
<div class="ui-widget">
<input id="dtags" class="form-control col-md-8" placeholder="Choose Delivery Town" required>
<input id="dtag" type="hidden" name="deltown">
</div>
<script>
(function() {
var towns = [
{ "label": "AANDRUS, Bloemfontein", "value": 1 },
{ "label": "AANHOU WEN, Stellenbosch", "value": 2 },
{ "label": "ABBOTSDALE, Western Cape", "value": 3 },
{ "label": "ABBOTSFORD, East London", "value": 4 },
{ "label": "ABBOTSFORD, Johannesburg", "value": 5 },
{ "label": "ABBOTSPOORT, Limpopo", "value": 6 },
{ "label": "ABERDEEN, Eastern Cape", "value": 7 },
{ "label": "ACKERVILLE, Witbank", "value": 8 },
{ "label": "ACORNHOEK, Mphumalanga", "value": 9 },
{ "label": "ACTIVIA PARK, Germiston", "value": 10 }
];
$("#dtags").autocomplete({
source: towns
});
// Overrides the default autocomplete filter function to search only from the beginning of the string
$.ui.autocomplete.filter = function (array, term) {
var matcher = new RegExp("^" + $.ui.autocomplete.escapeRegex(term), "i");
return $.grep(array, function (value) {
return matcher.test(value.label || value.value || value);
});
};
})();
//Uses event.preventDefault(); to halt the default and works as below
// $("#dtags").autocomplete({
//minLength: 1,
//source: towns,
//select: function(event, ui) {
//event.preventDefault();
//$("#dtags").val(ui.item.label);
//$("#dtag").val(ui.item.value);
//}
//});
//});
//});
//});
</script>

In case this could help anyone in the future, this is the script that I managed to get working successfully as per the question - slight change as to using an external data source:-
<script>
(function() {
var towns = [<?php require_once("towns.txt")?>];
$("#dtags").autocomplete({
source: towns,
select: function( event, ui ) {
$("#dtags").val(ui.item.label);
$("#dtag").val(ui.item.value);
return false;
}
});
// Overrides the default autocomplete filter function to search only from the beginning of the string
$.ui.autocomplete.filter = function (array, term) {
var matcher = new RegExp("^" + $.ui.autocomplete.escapeRegex(term), "i");
return $.grep(array, function (value) {
return matcher.test(value.label || value.value || value);
});
};
})();
</script>

Country->State->City Dependent dropdown showing 'object [Object]

I'm building a dependent dropdown for country, state and city. It's not going very well. I've done extensive research on the subject on Stackoverflow and other sites on the web for the past few days and have not been able to get the '#state' select object to populate states based on the selected '#country' select object which is populating countries from json just fine. The states are not populating after the country is selected based on the 'change' method. I have an 'if' statement which says, 'if the selected #country === 'US' (which displays as North America), then load the US states and territories .json file.
After fiddling around with the code, I have finally been able to get the '#state' dropdown to at least display 'object [Object]', so I know I'm getting closer to a solution. I'm not quite sure why it's displaying 'object[Object]' in the state dropdown. It may be a 'type' error of some sort where json is being displayed as an object instead of a string as it should but I don't understand how to fix this in the context of my code.
Any help would be greatly appreciated.
Here is the HTML:
<!doctype html>
<html>
<head>
<title>Country->State->City</title>
</head>
<body>
Country:
<select id="country">
<pre><option selected value="base">Select Country</option><pre>
</select>
State:
<select id="state">
<option selected value="base">Select state</option>
</select>
City:
<select id="city">
<option selected value="base">Select City</option>
</select>
<script type = "text/javascript" src="jquery-2.2.4.min.js"></script>
<script type = "text/javascript" src="custom.js"></script>
</body>
</html>
jQuery
$(function(){
let countryOptions;
let stateOptions;
let gaCitiesOps;
$.getJSON('countries.json',function(data){
$.each(data, function(i,country) {
countryOptions+=
'<option value= "'+country.code+'">'
+country.name+
'</option>';
});
$('#country').html(countryOptions);
});
$("#country").change(function(){
if($(this).val()==="US"){
$.getJSON('us_states.json',function(data){
$.each(data, function(stateCode,stateName) {
stateOptions+='<option value="'+stateCode+'">'
+stateName+
'</option>';
});
$('#state').html(stateOptions);
});
}
});
$("#state").change(function(){
if($(this).val()==="GA"){
$.getJSON('GA_cities.json',function(data){
$.each(data, function(statecode,city) {
gaCitiesOps +='<option value="'+statecode+'">'
+city+
'</option>';
});
$('#city').html(gaCitiesOps);
});
}
});
});
Countries.json
[
{
"code": "US",
"name": "North America"
},
{
"code": "AG",
"name": "Antigua"
},
{
"code": "AU",
"name": "Australia"
},
{
"code": "AT",
"name": "Austria"
},
{
"code": "BG" ,
"name": "Bulgaria"
},
{
"code": "CA",
"name": "Canada"
},
.....ect
us_states.json
[
{
"stateCode": "AL",
"name": "Alabama"
},
{
"stateCode": "AR",
"name": "Arkansas"
},
{
"stateCode": "AS",
"name": "American Samoa"
},
{
"stateCode": "AZ",
"name": "Arizona"
},
{
"stateCode": "CA",
"name": "California"
},
.....etc
GA_cities.json
[
{
"code": "ALB",
"name": "ALBANY"
},
{
"code": "AMR",
"name": "AMERICUS"
},
{
"code": "ATH",
"name": "ATHENS"
},
{
"code": "ATL",
"name": "ATLANTA"
},
{
"code": "AUG",
"name": "AUGUSTA"
},
{
"code": "BAI",
"name": "BAINBRIDGE"
},
....etc
Thanks for your consideration!

You're using $.each incorrectly. First argument is the index/key, second is the value. In your case you iterate over array of objects - so first argument is an index and second is each contained object. Use this code for states:
$.each(data, function(index,stateObj) {
stateOptions+='<option value="'+stateObj.stateCode+'">'
+stateObj.name+
'</option>';
});
$('#state').html(stateOptions);
});
And this for cities:
$("#state").change(function(){
if($(this).val()==="GA"){
$.getJSON('GA_cities.json',function(data){
$.each(data, function(index,city) {
gaCitiesOps +='<option value="'+city.code+'">'
+city.name+
'</option>';
});
$('#city').html(gaCitiesOps);
});
}
});
You can also add options using JS APIs which is slightly better than constructing the entire options HTML as a string and dumping it into html(). See this question for the alternative methods.

console.log() is your best friend. Try logging the values you get from $.each and you will know why you're getting [object Object].
$.each(data, function(stateCode, stateName));
Output is stateCode 0, stateName {stateCode: "AL", name: "Alabama"}
$.each arguments are (key, value) and you are looping over an array so key (stateCode in this case) is index of the array.
ES6; If you wanna be fancy you can destructure the arguments to
$.each(key, {stateCode, name});

JavaScript - Find an object among an array of objects, inside an array of objects

I'm using Vue, lodash, etc.
{
"street": {
"id": "1",
"streetName": "test",
"buildings": [
{
"id": "1",
"buildingName": "test"
}
]
}
}
I have a setup similar to this. This is a singular object, I basically have an array of these.
All I get is a building.id value.
From it, I need to be able to find the building it belongs to, and there isn't any direct list of buildings for me to access.
Currently
I'm using a nested loop to loop through each site until I find the one that has a building with that id. I don't know if I'm doing it correctly, it doesn't feel correct.
for(var i = 0; i < streets.length; i++){
for(var x = 0; x < streets[i].buildings.length;x++){
if(streets[i].buildings[x].id == '2aec6bed-8cdd-4043-9041-3db4681c6d08'){
}
}
}
Any tips? Thanks.

You can use a combination of filter and some methods, like this:
var result = streets.filter(function(s) {
return s.street.buildings.some(function(b) {
return b.id === searchedId;
});
});
Using .some() method will return true if any building of the iterated buildings has the searchedId.
Using .filter() will filter the streets array to return only street object where the call of some() method on its buildings will return true, in other words which meets the condition of having an idequal to searchedId.
Demo:
var streets = [{
"street": {
"id": "1",
"streetName": "test",
"buildings": [{
"id": "1",
"buildingName": "test"
}]
}
}, {
"street": {
"id": "1",
"streetName": "test",
"buildings": [{
"id": '2aec6bed-8cdd-4043-9041-3db4681c6d08',
"buildingName": "test"
}]
}
}];
var searchedId = '2aec6bed-8cdd-4043-9041-3db4681c6d08';
var result = streets.filter(function(s) {
return s.street.buildings.some(function(b) {
return b.id === searchedId;
});
});
console.log(result);

If you're trying to get all the buildings in all streets by a buildingId, this solves the problem:
streetsList.map(streetItem => streetItem.street.buildings.find(building => building.id === searchedBuildingId)).filter(v => v);
.filter(v => v) is for filtering out falsy values since we want a clean result here.
If there can be more than a single building in a street with the same id, then use .some instead of .find in the example.

Presumably you have a streets object that contains street objects, like:
var streets = [
street :{ ... },
street :{ ... },
...
];
So you need to step into each street and iterate over the buildings. A for loop should be fairly efficient since it can return as soon as it finds the building. I don't think any of the built-in looping methods will do that.
The code in the OP won't work, as streets[i].buildings must be streets[i].streets.buildings and if(streets[i].buildings[x].id must be if(streets[i].street.buildings[x].id.
Below is a working for loop version, there's also a version using recent Array methods which are very much slower even on a very small dataset. According to jsperf, the for loop version is about 100 times faster in Safari, 10 times faster in Firefox and 50 times faster in Chrome.
I also think the for loop code is much more readable and therefore maintainable.
var streets = [{
"street": {
"id": "1",
"streetName": "test",
"buildings": [{
"id": "1",
"buildingName": "test"
}, {
"id": "2",
"buildingName": "test"
}]
}
}, {
"street": {
"id": "2",
"streetName": "test",
"buildings": [{
"id": "3",
"buildingName": "test"
}]
}
}
];
function getBldById(data, id) {
for (var i=0, iLen=streets.length; i<iLen; i++) {
var street = streets[i].street;
for (var j=0, jLen=street.buildings.length; j<jLen; j++) {
if (street.buildings[j].id == id) {
return street.buildings[j];
}
}
}
return null;
}
console.log(getBldById(streets, '1'));
function getBldById2(data, id) {
return data.map(streetObj =>
streetObj.street.buildings.find(building =>
building.id === id)
).filter(v => v)[0];
}
console.log(getBldById2(streets, '1'));

You might be missing street property, right?
I mean it should be: streets[i].street.buildings[x].id

Mapping and binding nested objects and arrays

I have an object and within this object I have items and one of the items is an array which also contains objects. A sample of the data is shown below.
I am using knockout to bind this data to the view so I think I need to implement a double loop for returning the objects and the objects within the child array to be able to bind them in the view.
Sample data:
"singers": {
"ijiyt6ih": {
"id": ObjectId('ijiyt6ih'),
"name": "John",
"songs": [
{
"id": ObjectId('okoiu8yi'),
"songName": "Hello There",
"year": "1980"
},
{
"id": ObjectId('sewfd323'),
"songName": "No More",
"year": "1983"
}
]
},
"98usd96w": {
"id": ObjectId('98usd96w'),
"name": "Jack",
"songs": [
{
"id": ObjectId('iew342o3'),
"songName": "Hurry Up",
"year": "1985"
}
]
}
}
I need to find a way to appropriately loop through this so that I can modify the returned data to bind it to the viewModel using knockout.
Here is how my viewModel looks like:
singersViewModel = function(data) {
var self = {
singerId: ko.observable(data.id),
singerName: ko.observable(data.name),
songName: ko.observable(...),
songYear: ko.observable(...)
};
I am not sure if I will have to return two different sets of data or not.
As for the looping. I was able to loop and return the list of singers to display on the page but I am not able to get the list of songs displayed within each singer.
Here is my loop so far:
var self = {},
singer,
tempSingers = [];
self.singers = ko.observableArray([]);
for (singer in singers) {
if (singers.hasOwnProperty(singer)) {
tempSingers.push(new singersViewModel(singers[singer]));
}
}
self.singers(tempSingers);
I tried to duplicate the same type of loop for songs within this loop but i would get an error using hasOwnProperty because songs is an array.

In the included snippet you can see how you can map the original data to a viewmodel that can be bound to a view.
I've left the ids as regular properties, and converted the names into observables, so thatthey can be edited. At the bottom you can see the current viewmodel state.
There is also a sample view which iterates the list of singers, and also the list of song within each singer.
As you can see I'm implementing the solution using mapping. For mapping you need to implement a callback that receives each original object and returns a new one with a new structure. For example this part of the code
_.map(_singers, function(singer) {
return {
id: singer.id,
name: ko.observable(singer.name),
// ... songs:
})
iterates over each singer (the sample data in the question), and for each one creates a new object with the id, an observable which includes the name (and the mapping of songs, which I don't show in this fragment).
NOTE: I'm using lodash, but many browsers support map natively as an array function
var ObjectId = function (id) { return id; }
var singers = {
"ijiyt6ih": {
"id": ObjectId('ijiyt6ih'),
"name": "John",
"songs": [
{
"id": ObjectId('okoiu8yi'),
"songName": "Hello There",
"year": "1980"
},
{
"id": ObjectId('sewfd323'),
"songName": "No More",
"year": "1983"
}
]
},
"98usd96w": {
"id": ObjectId('98usd96w'),
"name": "Jack",
"songs": [
{
"id": ObjectId('iew342o3'),
"songName": "Hurry Up",
"year": "1985"
}
]
}
};
var SingersVm = function(_singers) {
var self = this;
self.singers = _.map(_singers, function(singer) {
return {
id: singer.id,
name: ko.observable(singer.name),
songs: _.map(singer.songs, function(song) {
return {
name: ko.observable(song.songName),
id: song.id
};
})
};
});
return self;
};
var vm = new SingersVm(singers);
//console.log(vm);
ko.applyBindings(vm);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/3.10.1/lodash.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div data-bind="foreach: singers">
<div>
<input data-bind="value: name"/> (<span data-bind="text: id"></span>)
<ul data-bind="foreach:songs">
<li>
<input data-bind="value: name"/> (<span data-bind="text: id"></span>)
</li>
</ul>
</div>
</div>
<pre data-bind="html: ko.toJSON($root,null,2)">
</pre>

Populate a variable using jQuery based on selections in a drop down

I'm trying to build a nested array in jQuery based on a user's selection from a drop down menu. This will be used in a JSON request at a later date.
So far my code does produce (almost) the required result, however no matter order i select the options from my drop down menu, the output (which i log in the console at the end) is always the same.
$('#comboGenre').change(function () {
var values = $('#comboGenre').val();
var parsedJSON = JSON.parse($data); //Data returned from ajax request
for (var i = 0; i < values.length; i += 1) {
$genreList = parsedJSON.genre[i];
console.log($genreList);
}
});
So if i select RPG and Action from my drop down, the output gives me RPG and Driving. If i selected RPG, Driving and Action (in that order), i get what i would expect RPG, Driving and Action.
So it's just iterating through my JSON, when really it should be returning the 'selected' option.
How can i achieve this?
My JSON looks like this if it's useful:
{"genres": [{
"genre": "RPG",
"publishers": [{
"publisher": "Square",
"games": [{
"game": "FFX",
"rating": [
12, 15
]
}]
}]
},
{
"genre": "Driving",
"publishers": [{
"publisher": "Turn10",
"games": [{
"game": "Forza",
"rating": [
5
]
}]
}]
},
{
"genre": "Action",
"publishers": [{
"publisher": "EA",
"games": [{
"game": "COD",
"rating": [
18, 20
]
}]
}]
}
]}
EDIT:
I've also tried this:
$('#comboGenre').change(function () {
var parsedJSON = JSON.parse($data);
$genreList = "";
$.each(parsedJSON.genres, function(index, value){
$genreList = parsedJSON.genres[index];
console.log($genreList);
});
});
And i end up getting ALL the objects in my JSON, so from here, i'm only wanting to add the selected object to the $genreList variable.

If you broke out some of the logic and created a genre finding function and used the selected string to find the proper object you could then put the object into the variable you will use later. I do some checking to ensure that the genre that has been selected isn't already in my array which is because I am using the multiple select
JSFiddle: http://jsfiddle.net/vkTFq/
Code:
$(function(){
var selectedGenres = [];
var genres =[{"genre":"RPG","publishers":[{"publisher":"Square","games":[{"game":"FFX","rating":[12,15]}]}]},{"genre":"Driving","publishers":[{"publisher":"Turn10","games":[{"game":"Forza","rating":[5]}]}]},{"genre":"Action","publishers":[{"publisher":"EA","games":[{"game":"COD","rating":[18,20]}]}]}]
$('#comboGenre').change(function() {
$(this).find(":selected").each(function() {
var selectedGenre = findGenre($(this).val())
if (!genreAlreadySelected(selectedGenre.genre)) {
selectedGenres.push(selectedGenre);
};
});
console.log (JSON.stringify(selectedGenres));
});
function genreAlreadySelected(genre){
for(var i = 0; i < selectedGenres.length; i++){
if (genre == selectedGenres[i].genre) {
return true;
};
return false;
}
}
function findGenre(genre){
for(var i = 0; i < genres.length; i ++){
console.log(genre)
if(genre == genres[i].genre){
return genres[i];
}
}
};
});