Develop Reference

Duplicates in array of numbers failing

I have the following function to check for duplicates;
function hasDuplicates(array) {
return (new Set(array)).size !== array.length;
}
I use this to check if someone has not provided two of the same items to sell from his or her inventory, cause we won't allow him or her getting twice the amount of money he or her should.
It worked for a while but then I think someone who meant harm came in and breached it somehow. I've been testing for a while now and found that I can bypass this sytem by having my array like the following (ids of my inventories);
var array = [312, 329, 932]; //normal > should bypass
var array = [333, 333, 333]; //not normal > can't bypass
but then if you do this it allows you to bypass;
var array = [333, '333/', '333//'];
is there any way I can solve this quickily?
Edit
Database query that looks up the data anyways even if its provided as 333// strings.
database.query('SELECT * FROM `inventories` WHERE `id` = ' + database.pool.escape(id), function(err, row){

array.every(n => Number.isInteger(n))
Just ensure that everything is a number in the array.

You can do something like the following with hash,
and use regex to remove the special characters and leave it with a number only, (casting it to Number is also recommended).
var array = ['333//', 212, '333/'];
var hash = {};
array.forEach(num => {
if(!Number.isInteger(num)) {
num = Number(num.replace(/[^\w\s]/gi, ''));
}
if(!hash[num]) {
hash[num] = num;
}
})
var newArray = Object.values(hash);
console.log(newArray);

how can I filter an array without losing the index?

I have two really long arrays containing "picture names" and "picture files". The first one represents the actual name of the pictures, while the second one is just the file name. For example:
picturenames[0] = '0 - zero';
picturenames[1] = '1 - one';
picturenames[2] = '1 o\'clock';
...
picturefiles[0] = 'numbers-zero.jpg';
picturefiles[1] = 'numbers-one.jpg';
picturefiles[2] = 'time-1.jpg';
...
I have about 1000 items in each array in several languages (the picture files are always the same). I'm "recycling" these arrays from the previous application to save some time and avoid rewriting everything anew.
Desirable functionality: using the user's input in a textbox I want to filter the picturenames array and then show the correspondant picturefiles image.
The issue I'm facing: when I filter the picturenames array I lose the index and I can't "reach" the picture file name.
This is the code I'm using to filter the picturenames array.
var matches = picturenames.filter(function(windowValue){
if(windowValue) {
return windowValue.indexOf(textToFindLower) >= 0;
}
});
What would be the best way to do this?
UPDATE: the solution proposed by Ahmed is the best one, but for time reasons and negligible performance issues I'm just using a for loop to search trough the array, as follows:
var matchesCounter = new Array();
for (i = 0; i < picturenames.length; i++) {
if (picturenames[i].indexOf(textToFindLower) >= 0) {
matchesCounter.push(i);
}
}
console.log(matchesCounter);
for (i = 0; i < matchesCounter.length; i++) {
console.log(picturenames[i]);
console.log(picturefiles[i]);
}

Try this:
const foundIndicies = Object.keys(picturenames).filter(pictureName => {
pictureName.includes(textToFindLower)
});
// reference picturefiles[foundIndicies[0]] to get the file name
Though, it would be far nicer to have both the name and the file in a single object, like so:
const pictures = [
{
name: '0 - zero',
file: 'numbers-zero.jpg',
},
{
name: '1 - one',
file: 'numbers-one.jpg',
}
];
const foundPictures = pictures.filter(picture => picture.name.includes('zero'));
if (foundPictures[0]) console.log(foundPictures[0].file);

You can add one property index during the filtering time, then later on you can use the index.
var matches = picturenames.filter(function(windowValue, index){
if(windowValue) {
windowValue.index = index;
return windowValue.comparator(textToFindLower) >= 0;// Need to define comparator function
}
});
Later on you can access by using like follows:
picturefiles[matches[0].index]
However, the solution will work on object, not primitive type string.
If your data type is string, then you have to convert as object and put the string as a property value like name. The snippet is given below:
var picturenames = [];
var picturefiles = [];
picturenames.push({name:'0 - zero'});
picturenames.push({name:'1 - one'});
picturenames.push({name:'1 o\'clock'});
picturefiles.push({name:'numbers-zero.jpg'});
picturefiles.push({name:'numbers-one.jpg'});
picturefiles.push({name: 'time-1.jpg'});
var textToFindLower = "0";
var matches = picturenames.filter(function(windowValue, index){
if(windowValue) {
windowValue.index = index;
return windowValue.name.indexOf(textToFindLower) >= 0;
}
});
console.log(matches);

How to remove all characters before specific character in array data

I have a comma-separated string being pulled into my application from a web service, which lists a user's roles. What I need to do with this string is turn it into an array, so I can then process it for my end result. I've successfully converted the string to an array with jQuery, which is goal #1. Goal #2, which I don't know how to do, is take the newly created array, and remove all characters before any array item that contains '/', including '/'.
I created a simple work-in-progress JSFiddle: https://jsfiddle.net/2Lfo4966/
The string I receive is the following:
ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC
ABCD/ in the string above can change, and may be XYZ, MNO, etc.
To convert to an array, I've done the following:
var importUserRole = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',');
Using console.log, I get the following result:
["ABCD", "ABCD/Admin", "ABCD/DataManagement", "ABCD/XYZTeam", "ABCD/DriverUsers", "ABCD/RISC"]
I'm now at the point where I need the code to look at each index of array, and if / exists, remove all characters before / including /.
I've searched for a solution, but the JS solutions I've found are for removing characters after a particular character, and are not quite what I need to get this done.

You can use a single for loop to go through the array, then split() the values by / and retrieve the last value of that resulting array using pop(). Try this:
for (var i = 0; i < currentUserRole.length; i++) {
var data = currentUserRole[i].split('/');
currentUserRole[i] = data.pop();
}
Example fiddle
The benefit of using pop() over an explicit index, eg [1], is that this code won't break if there are no or multiple slashes within the string.
You could go one step further and make this more succinct by using map():
var importUserRole = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',').map(function(user) {
return user.split('/').pop();
});
console.log(currentUserRole);

You can loop through the array and perform this string replace:
currentUserRole.forEach(function (role) {
role = role.replace(/(.*\/)/g, '');
});

$(document).ready(function(){
var A=['ABCD','ABCD/Admin','ABCD/DataManagement','ABCD/XYZTeam','ABCD/DriverUsers','ABCD/RISC'];
$.each(A,function(i,v){
if(v.indexOf('/')){
var e=v.split('/');
A[i]=e[e.length-1];
}
})
console.log(A);
});

You could replace the unwanted parts.
var array = ["ABCD", "ABCD/Admin", "ABCD/DataManagement", "ABCD/XYZTeam", "ABCD/DriverUsers", "ABCD/RISC"];
array = array.map(function (a) {
return a.replace(/^.*\//, '');
});
console.log(array);

var importUserRole = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',');
for(i=0;i<currentUserRole.length;i++ ){
result = currentUserRole[i].split('/');
if(result[1]){
console.log(result[1]+'-'+i);
}
else{
console.log(result[0]+'-'+i);
}
}
In console, you will get required result and array index

I would do like this;
var iur = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC',
arr = iur.split(",").map(s => s.split("/").pop());
console.log(arr);

You can use the split method as you all ready know string split method and then use the pop method that will remove the last index of the array and return the value remove pop method
var importUserRole = ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',');
for(var x = 0; x < currentUserRole.length; x++;){
var data = currentUserRole[x].split('/');
currentUserRole[x] = data.pop();
}
Here is a long way
You can iterate the array as you have done then check if includes the caracter '/' you will take the indexOf and substact the string after the '/'
substring method in javaScript
var importUserRole = 'ABCD,ABCD/Admin,ABCD/DataManagement,ABCD/XYZTeam,ABCD/DriverUsers,ABCD/RISC';
var currentUserRole = importUserRole.split(',');
for(var x = 0; x < currentUserRole.length; x++){
if(currentUserRole[x].includes('/')){
var lastIndex = currentUserRole[x].indexOf('/');
currentUserRole[x] = currentUserRole[x].substr(lastIndex+1);
}
}

access javascript array element by JSON object key

I have an array that looks like this
var Zips = [{Zip: 92880, Count:1}, {Zip:91710, Count:3}, {Zip:92672, Count:0}]
I would like to be able to access the Count property of a particular object via the Zip property so that I can increment the count when I get another zip that matches. I was hoping something like this but it's not quite right (This would be in a loop)
Zips[rows[i].Zipcode].Count
I know that's not right and am hoping that there is a solution without looping through the result set every time?
Thanks

I know that's not right and am hoping that there is a solution without
looping through the result set every time?
No, you're gonna have to loop and find the appropriate value which meets your criteria. Alternatively you could use the filter method:
var filteredZips = Zips.filter(function(element) {
return element.Zip == 92880;
});
if (filteredZips.length > 0) {
// we have found a corresponding element
var count = filteredZips[0].count;
}
If you had designed your object in a different manner:
var zips = {"92880": 1, "91710": 3, "92672": 0 };
then you could have directly accessed the Count:
var count = zips["92880"];

In the current form, you can not access an element by its ZIP-code without a loop.
You could transform your array to an object of this form:
var Zips = { 92880: 1, 91710: 3 }; // etc.
Then you can access it by
Zips[rows[i].Zipcode]
To transform from array to object you could use this
var ZipsObj = {};
for( var i=Zips.length; i--; ) {
ZipsObj[ Zips[i].Zip ] = Zips[i].Count;
}

Couple of mistakes in your code.
Your array is collection of objects
You can access objects with their property name and not property value i.e Zips[0]['Zip'] is correct, or by object notation Zips[0].Zip.
If you want to find the value you have to loop

If you want to keep the format of the array Zips and its elements
var Zips = [{Zip: 92880, Count:1}, {Zip:91710, Count:3}, {Zip:92672, Count:0}];
var MappedZips = {}; // first of all build hash by Zip
for (var i = 0; i < Zips.length; i++) {
MappedZips[Zips[i].Zip] = Zips[i];
}
MappedZips is {"92880": {Zip: 92880, Count:1}, "91710": {Zip:91710, Count:3}, "92672": {Zip:92672, Count:0}}
// then you can get Count by O(1)
alert(MappedZips[92880].Count);
// or can change data by O(1)
MappedZips[92880].Count++;
alert(MappedZips[92880].Count);
jsFiddle example

function getZip(zips, zipNumber) {
var answer = null;
zips.forEach(function(zip){
if (zip.Zip === zipNumber) answer = zip;
});
return answer;
}
This function returns the zip object with the Zip property equal to zipNumber, or null if none exists.

did you try this?
Zips[i].Zip.Count

Assign new value to variable using itself

This doesn't work but I can't see why it wouldn't? any help people? :)
params = qs.split("=", 2),
id = params[1];
if(id.indexOf("?") != -1){
id = id.split("?", 1);
}
basically I want to change the value of 'ID' if the IF statement is true, if not.. it skips it and the value Id remains the default.
Thanks

The result of id = id.split("?", 1) is an array (of at most 1 item), but I think you want id to be a string. That would explain why id is not a string like you want.
I agree with the other comments. Please show us the URL string you want to parse and tell us which piece you're trying to get. Usually, you look for ? first, separate after that and then divide up various key=value sections.
If you had a URL like this:
http://www.example.com?foo=bar
Here's a simple function that gets you all the query parameters into an object:
function getParms(url) {
var sections, key, pieces = url.split("?");
var results = {};
if (pieces.length > 1) {
sections = pieces[1].split("&");
for (var i = 0; i < sections.length; i++) {
key = sections[i].split("=");
results[key[0]] = key[1];
}
}
return(results);
}
Working demo: http://jsfiddle.net/jfriend00/kNG3u/