Develop Reference

JS Alert when items collected?

I have created a maze game where the user must collect all the coins in the maze, however I am trying to make an alert appear once the user has collected all the coins, not in any particular order just in general. The alert is being very troublesome at the moment and not working correctly and I'm not sure where I am going wrong based off my research into the matter. I am new to JavaScript so apologies for any clear mistakes.
EDIT I GOT TOLD TO REPHRASE MY QUESTION MORE DIRECTLY - SO THIS ISN'T A DUPLICATE QUESTION. I ALSO HAVE A MAP DECLARDED BUT CANNOT UPLOAD AS IT'S TOO MUCH CODE.
Also, when I say not working correctly, it will appear at random counts as supposed to when the last reward has been collected.
var el = document.getElementById('game');
function drawWorld(){
el.innerHTML = '';
for(var y = 0; y < map.length ; y = y + 1) {
for(var x = 0; x < map[y].length ; x = x + 1) {
if (map[y][x] === 1) {
el.innerHTML += "<div class='borders'></div>";
} else if (map[y][x] === 2) {
el.innerHTML += "<div class='reward'></div>";
} else if (map[y][x] === 3) {
el.innerHTML += "<div class='ground'></div>";
} else if (map[y][x] === 5) {
el.innerHTML += "<div class='character'></div>";
} else if (map[y][x] === 4) {
el.innerHTML += "<div class='ship'></div>";
}
}
el.innerHTML += "<br>";
}
winGame();
}
function restartGame(){
window.location.reload();
}
function winGame(){
if (!map[5].includes(2) && !map[2].includes(2) &&
!map[3].includes(2) && !map[2].includes(2) && !map[4].includes(2)
&& !map[2].includes(2))
alert("Well done!");
}
drawWorld();
document.onkeydown = function(event){
if (event.keyCode === 37){
if ( map[character.y][character.x-1] !== 1){
map[character.y][character.x] = 3;
character.x = character.x - 1;
map[character.y][character.x] = 5;
drawWorld();
}
} else if (event.keyCode === 38){
if ( map[character.y-1][character.x] !== 1){
map[character.y][character.x] = 3;
character.y = character.y - 1;
map[character.y][character.x] = 5;
drawWorld();
}
} else if (event.keyCode === 39){
if ( map[character.y][character.x+1] !== 1){
map[character.y][character.x] = 3;
character.x = character.x + 1;
map[character.y][character.x] = 5;
drawWorld();
}
} else if (event.keyCode === 40){
if ( map[character.y+1][character.x] !== 1){
map[character.y][character.x] = 3;
character.y = character.y + 1;
map[character.y][character.x] = 5;
drawWorld();
}
}
console.log(map)
}

clear javascript : determine which link was clicked

I have a cycle of links and I determined click event on them. And I want to define if navbar[1].clicked == true {doing something} else if navbar[2].cliked == true {doing something} etc. "By if else in " reveal functional callbackFn".
Here is the code:
var navbar = document.getElementById("navbar").getElementsByTagName("a");
for (var i = 0; i < navbar.length; i++) {
navbar[i].addEventListener('click', function() { reveal('top'); });
}
function reveal(direction) {
callbackFn = function() {
// this is the part where is running the turning of pages
classie.remove(pages[currentPage], 'page--current');
if (navbar[1].clicked == true) {
currentPage = 0;
} else if(navbar[1].clicked == true) {
currentPage = 1;
} else if(navbar[2].clicked == true) {
currentPage = 2;
} else if(navbar[3].clicked == true) {
currentPage = 3;
} else if(navbar[4].clicked == true) {
currentPage = 4;
};
classie.add(pages[currentPage], 'page--current');
};
}

This is typically a problem of closure.
You can make the following change
Here the call back function of the addEventListener is an IIFE, & in the reveal function pass the value of i
var navbar = document.getElementById("navbar").getElementsByTagName("a");
for (var i = 0; i < navbar.length; i++) {
navbar[i].addEventListener('click', (function(x) {
reveal('top',x);
}(i))};
}
In this function you will have access to
function reveal(direction,index) {
// not sure what this function is mean by, but you will have the value of `i` which is denote the clicked element
callbackFn = function() {
// this is the part where is running the turning of pages
classie.remove(pages[currentPage], 'page--current');
if (index == 1) {
currentPage = 0;
} else if (index == 1) {
currentPage = 1;
} else if (index == 2) {
currentPage = 2;
} else if (index == 3) {
currentPage = 3;
} else if (index == 4) {
currentPage = 4;
};
classie.add(pages[currentPage], 'page--current');
};
}

Here is the solution in my case.
Thank you brk for helping in any case, thanks again.
// determine clicked item
var n;
$('#navbar a').click(function(){
if($(this).attr('id') == 'a') {
n = 0;
} else if($(this).attr('id') == 'b') {
n = 1;
} else if($(this).attr('id') == 'c') {
n = 2;
} else if($(this).attr('id') == 'd') {
n = 3;
} else if($(this).attr('id') == 'e') {
n = 4;
};
});
var pages = [].slice.call(document.querySelectorAll('.pages > .page')),
currentPage = 0,
revealerOpts = {
// the layers are the elements that move from the sides
nmbLayers : 3,
// bg color of each layer
bgcolor : ['#52b7b9', '#ffffff', '#53b7eb'],
// effect classname
effect : 'anim--effect-3'
};
revealer = new Revealer(revealerOpts);
// clicking the page nav
document.querySelector("#a").addEventListener('click', function() { reveal('cornertopleft'); });
document.querySelector("#b").addEventListener('click', function() { reveal('bottom'); });
document.querySelector("#c").addEventListener('click', function() { reveal('left'); });
document.querySelector("#d").addEventListener('click', function() { reveal('right'); });
document.querySelector("#e").addEventListener('click', function() { reveal('top'); });
// moving clicked item's `n` into the function
function reveal(direction) {
var callbackTime = 750;
callbackFn = function() {
classie.remove(pages[currentPage], 'page--current');
currentPage = n;
classie.add(pages[currentPage], 'page--current');
};
revealer.reveal(direction, callbackTime, callbackFn);
}

NaN error equation

In this javascript code I try to solve a quadratic equation, I've been working on it for an hour and this should tell me the value of a, b and c where y is a(x^2). I'm a relative javascript beginner and would love some help. Why are the values of a, b and c not numbers? The variable names are in italian, in english and in something else(Not even I know what), but I commented what they are. That's one of my bad traits as a student that usually works alone, sorry if it's not easy to understand.
<script type="text/javascript">
var equa=prompt("Scrivi l'equazione senza spazi usando x come incognita e y come x^2");
var a = 0.0; b = 0.0; c = 0.0;//ax2+bx+c
var prima = true; //before or after equal?
var ope = 1;//1add 2sub 3mul 4div
var lasto = 0.0;//last number, used for div and mul
var lastos = 3; //1a2b3c
var errore=0;//is something messed up?
for(var i = 0; i < equa.length;i=i){
if(equa.charAt(i)=='='){
prima = false;
i++;
}else if(equa.charAt(i)=='+'){
ope=1;
i++;
}else if(equa.charAt(i)=='-'){
ope=2;
i++;
}else if(equa.charAt(i)=='*'){
ope=3;
i++;
}else if(equa.charAt(i)=='/'){
ope=4;
i++;
}else{
var nume = "";//Current number in string form
while(i<equa.length && equa.charAt(i)>'0' && equa.charAt(i)<'9'){
nume+=equa.charAt(i);
i++;
}
var lasnum = 0.0;//current number in float form
var lasval = 3; //1a2b3c
if(equa.charAt(i) == 'x'){
lasnum=parseFloat(nume);
lasval = 2;
}else if(equa.charAt(i) == 'y'){
lasnum=parseFloat(nume);
lasval = 1;
}else{
lasnum = parseFloat(nume);
lasval=3;
}
i++;
if( (ope == 1 || ope == 2) && !(equa.charAt(i) =='*' || equa.charAt(i) == '/')){
if(lasval == 1){
if(prima) a+=lasnum;
else a-=lasnum;
}
else if(lasval == 2){
if(prima) b+=lasnum;
else b-=lasnum;
}
else {
if(prima) c+=lasnum;
else c-=lasnum;
}
}else if( (ope==1 || ope == 2) && (equa.charAt(i) =='*' || equa.charAt(i) == '/')){
//zitto e fermo
lasto=lasnum;
lastos=lasval;
}else if( (ope==3||ope == 4)){
if(ope==3){
if(lastos==3){
lasnum*=lasto;
}
if(lastos == 2){
if(lastval==3){
lasnum*=lasto;
lastval=2;
}
if(lastval==2){
lasnum*=lasto;
lastval=1;
}
if(lastval==1){
errore=1;
}
}
if(lastos == 1){
if(lastval == 3){
lasnum*=lasto;
lastval=1;
}else{
errore=1;
}
}
}
if(ope == 4){
if(lastos == 1){
if(lastval==3){
lasnum/=lasto;
lastval=1;
}
if(lastval==2){
lasnum/=lasto;
lastval=2;
}
if(lastval==1){
lasnum/=lasto;
lastval=3;
}
}
if(lastos == 2){
if(lastval==1){
errore=1;
}
if(lastval==2){
lasnum/=lasto;
lastval=3;
}
if(lastval==3){
lasnum/=lasto;
lastval=2;
}
}
if(lastos == 3){
if(lastval==3){
lasnum/=lasto;
}else{
errore=1;
}
}
}
if(equa.charAt(i) =='*' || equa.charAt(i) == '/'){
lasto=lasnum;
lasto=lasval;
}else{
if(lasval == 1){
if(prima) a+=lasnum;
else a-=lasnum;
}
else if(lasval == 2){
if(prima) b+=lasnum;
else b-=lasnum;
}
else {
if(prima) c+=lasnum;
else c-=lasnum;
}
lasto=0;
lastos=3;
}
}
}
}
if(errore==0){
alert("a ="+a+" b="+b+" c="+c);
}else{
alert("AOOOOOOo");
}
</script>

Since the expected input should be in the format "15y+3x+5=20" for example, then this is a simple regular expression:
var equa = prompt("Scrivi l'equazione senza spazi usando x come incognita e y come x^2");
var regex = /^([0-9.]+)y\+([0-9.]+)x\+([0-9.]+)=([0-9.]+)$/;
var matches = regex.exec(equa);
if (matches) {
var a = parseFloat(matches[1]);
var b = parseFloat(matches[2]);
var c = parseFloat(matches[3]) - parseFloat(matches[4]);
var discriminant = b*b - 4*a*c;
if (discriminant < 0) {
alert('No real solutions');
}
else {
var root = Math.sqrt(discriminant);
alert('Root: ' + ((-b + root)/(2*a)) + ', ' + ((-b - root)/(2*a)));
}
}
else {
alert("AOOOOOOo");
}

How to use AJAX or JSON in this code?

I am creating a website application that allows users to select a seat, if it is not already reserved, and reserve it.
I have created a very round about way of getting the seats that are previously reserved using iFrames, however that was temporarily, now I need to make it secure and "proper javascript code" using proper practices. I have no clue what AJAX (or JSON) is, nor how to add it to this code, but it needs to get the file "seatsReserved"+this.id(that is the date)+"Que.html" and compare the string of previously reserved seats to see which class to make the element. If this is horrible, or if any of the other things could work better, I am open to criticism to everything. Thank you all!
Here is the javascript code:
A little side note, all of the if statements are due to different amount of seats in each row
<script>
var i = " 0 ";
var counter = 0;
var leng=0;
document.getElementById("Show1").addEventListener("click", changeDay);
document.getElementById("Show2").addEventListener("click", changeDay);
document.getElementById("Show3").addEventListener("click", changeDay);
function changeDay() {
var iFrame = document.getElementById("seatList");
iFrame.src = "seatsReserved" + this.id + "Que.html";
document.getElementById('date').innerHTML = this.id;
var seatsTaken = iFrame.contentWindow.document.body.innerHTML;
var k = 0;
let = 'a';
var lc = 0;
for (lc = 1; lc <= 14; lc++) {
if (lc == 1) {
leng = 28;
}
else if (lc == 2) {
leng = 29;
}
else if (lc == 3) {
leng = 32;
}
else if (lc == 4 || lc == 6 || lc == 12 || lc == 14) {
leng = 33;
}
else if (lc == 5 || lc == 13) {
leng = 34;
}
else if (lc == 8 || lc == 10) {
leng = 35;
}
else {
leng = 36;
}
for (k = 1; k <= leng; k++) {
if (seatsTaken.indexOf((" " +
let +k + " ")) <= -1) {
seat = document.getElementById(let +k);
seat.removeEventListener("click", selectedSeat);
}
else {
document.getElementById(let +k).className = "openseat";
document.getElementById(let +k).removeEventListener("click", doNothing);
}
}
let = String.fromCharCode(let.charCodeAt(0) + 1);
}
}
function loadChanges() {
var iFrame = document.getElementById("seatList");
var seatsTaken = iFrame.contentWindow.document.body.innerHTML;
var k = 0;
let = 'a';
var lc = 0;
var leng = 0;
for (lc = 1; lc <= 14; lc++) {
if (lc == 1) {
leng = 28;
}
else if (lc == 2) {
leng = 29;
}
else if (lc == 3) {
leng = 32;
}
else if (lc == 4 || lc == 6 || lc == 12 || lc == 14) {
leng = 33;
}
else if (lc == 5 || lc == 13) {
leng = 34;
}
else if (lc == 8 || lc == 10) {
leng = 35;
}
else {
leng = 36;
}
for (k = 1; k <= leng; k++) {
if (seatsTaken.indexOf((" " +
let +k + " ")) <= -1) {
seat = document.getElementById(let +k);
seat.addEventListener("click", selectedSeat);
seat.className = "openseat";
}
else {
document.getElementById(let +k).className = "notAvailible";
document.getElementById(let +k).addEventListener("click", doNothing);
}
}
let = String.fromCharCode(let.charCodeAt(0) + 1);
}
i = " 0 ";
counter = 0;
document.getElementById("seatString").innerHTML = i;
document.getElementById("getSeats").value = i;
document.getElementById("seatnums").innerHTML = counter;
}
i = document.getElementById("seatString").innerHTML;
counter = document.getElementById("seatnums").innerHTML;
function selectedSeat() {
var w = this.id;
var l = (" " + w);
var b = (" " + w + " ");
if (counter < 5) {
if (i.indexOf(b) <= 0) {
this.className = "closedseat";
i = i + b;
i = i.replace(" 0 ", " ");
document.getElementById("seatString").innerHTML = i;
document.getElementById("getSeats").value = i;
counter = counter + 1;
document.getElementById("seatnums").innerHTML = counter;
}
else if (i.indexOf(b) > 0) {
this.className = "openseat";
i = i.replace(b, "");
document.getElementById("seatString").innerHTML = i;
document.getElementById("getSeats").value = i;
counter = counter - 1;
document.getElementById("seatnums").innerHTML = counter;
}
}
else if (i.indexOf(b) > 0) {
this.className = "openseat";
i = i.replace(b, "");
document.getElementById("seatString").innerHTML = i;
document.getElementById("getSeats").value = i;
counter = counter - 1;
document.getElementById("seatnums").innerHTML = counter;
}
}
function doNothing() {
}
var rannum = Math.random() * 1000;
document.getElementById('getConfirmation').value = rannum;
</script>

How to display the names of all controls(textboxes & dropdowns) which are empty in my page

I get the message Validation Failed if any of my controls are empty, but I would want to display the names of the controls which are empty. These controls are dynamically created on the page.
Below is the code that I am using now
function validateinput() {
var arrTextBox = document.getElementsByTagName("input");
var ddlTextBox = document.getElementsByTagName("select");
var retVal = 1;
for (i = 0; i < arrTextBox.length; i++) {
if (arrTextBox[i].type == "text" && arrTextBox[i].getAttribute("IsMandatory") == "Y" && arrTextBox[i].value == ""){
retVal = 0;
}
}
for (j = 0; j < ddlTextBox.length; j++) {
if (ddlTextBox[j].getAttribute("IsMandatory") == "Y" && ddlTextBox[j].value == "") {
retVal = 0;
}
}
if (retVal == 0) {
alert("Validation Failed");
return false;
}
else {
alert("Validation Success");
return true;
}
}

Okay, I see from the comments that you need some more specific assistance. Try this:
function validateinput() {
var emptySelects = '';
var emptyTextboxes = '';
var arrTextBox = document.getElementsByTagName("input");
var ddlTextBox = document.getElementsByTagName("select");
var retVal = 1;
for (i = 0; i < arrTextBox.length; i++) {
if (arrTextBox[i].type == "text" && arrTextBox[i].getAttribute("IsMandatory") == "Y" && arrTextBox[i].value == ""){
retVal = 0;
emptyTextboxes+= ' ' + arrTextBox[i].name;
}
}
for (j = 0; j < ddlTextBox.length; j++) {
if (ddlTextBox[j].getAttribute("IsMandatory") == "Y" && ddlTextBox[j].value == "") {
retVal = 0;
emptySelects += ' ' + ddlTextBox[j].name;
}
}
if (retVal == 0) {
alert("Validation Failed");
if (emptyTextboxes != '') alert('The following textboxes are empty:' + emptyTextboxes);
if (emptySelects != '') alert('The following selections are empty:' + emptySelects);
return false;
}
else {
alert("Validation Success");
return true;
}
}