We Keep Coding

How can I pass the zip to the button function?

I did wrap this in a form with a submit button, but realized that this attempted to go to a new page without performing the logic. How can I pass the zip code to the onclick button event? If this is completely wrong, can you provide guidance onto how to perform this correctly.
<input type="text" placeholder="Zip Code" pattern="[0-9]{5}" name="zip" required />
<button id="checker">Go!</button>
<script>
var b = document.getElementById("checker");
b.addEventListener("click", function checkZipCode(zip) {
var zipCodes = [26505, 26501, 26507, 26506];
for (i = 0; i <= zipCodes.length - 1; i++) {
if (zip == zipCodes[i]) {
alert("YES");
break;
}
}
}
</script>

You need to get the value of your input and you can do this with document.querySelector('[name="zip"]').value
var b = document.getElementById("checker");
b.addEventListener("click", function checkZipCode(zip) {
var zip = document.querySelector('[name="zip"]').value;
var zipCodes = [26505, 26501, 26507, 26506];
for (i = 0; i <= zipCodes.length - 1; i++) {
if (zip == zipCodes[i]) {
alert("YES");
break;
}
}
})
<input type="text" placeholder="Zip Code" pattern="[0-9]{5}" name="zip" required />
<button id="checker">Go!</button>

Just use getElementById('ELEMENT_NAME_HERE').value like so:
Go!
<script>
var b = document.getElementById("checker");
b.addEventListener("click", function checkZipCode(zip){
console.log('Clicked');
var enteredZip = document.getElementById("zip").value;
console.log(enteredZip);
var zipCodes=[26505, 26501, 26507, 26506];
for(i=0; i<=zipCodes.length-1; i++){
if(zip == zipCodes[i]){
alert("YES");
break;
}}});
</script>
https://plnkr.co/edit/ptyUAItwyaSmZXsD81xK?p=preview
You can't pass it in.

basically if this myfunction() will return a false then the form would not be submitted;
Also this would only be performed at the time of submittion of the form
https://www.w3schools.com/jsref/event_onsubmit.asp
<form onsubmit="myFunction()">
Enter name: <input type="text">
<input id='input-id' type="submit">
</form>
<script>
myfunction(){
if(/*some condition*/)
{
return false;
}
</script>
Also few things to consider since you seem new and people here are giving you very correct but specific solutions.
if you add a button to inside tag, that would submit the form on clicking it.
That is why many use a div which looks like a button by css. Mainly a clean solution to override the Button submit and also you can simply submit the form by Javascript.

Send only filled fields via GET

Look at simple form below:
<form method="GET" action="index.php">
<input type="text" name="price_min" >Min
<input type="text" name="price_max" >Max
</form>
When I send form with filled only one field, in my url I get empty values for not filled keys
(ex. index.php?price_min=).
Question:
How to remove empty keys from url?

You can parse serialized string and remove blank values. Then you can use post to necessary api using jQuery.
Sample
JSFiddle
$("#btn").on("click", function() {
var formjson = $("#frmTest").serialize();
var result = formjson.split("&").filter(function(val) {
return val.split("=")[1].length > 0;
}).join("&")
console.log("Serialized String:", formjson);
console.log("Processed String:", result);
// $.get('action.php', formjson, function(response){ ... })
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.0/jquery.min.js"></script>
<form id="frmTest">
<input type="text" name="price_min">Min
<input type="text" name="price_max">Max
</form>
<button id="btn">Test Serialize</button>

Use jQuery to send the fields like this
$('your_form').submit(function() {
var min_price = $("#min_price").val();
var max_price = $("#max_price").val();
var string = "";
if(min_price.length > 0){
string += "min_price="+min_price
}
if(max_price.length > 0){
string += "&max_price="+max_price
}
window.location.href = 'index.php?'+string;
});
Hope it helps!

Javascript form submits to new page -- how can I keep it on the same page?

beginner programmer here. Trying to create a very primitive "chat interface", in JSP where I type in some words, they're stored in an array, then, ideally, spit back out on the same page. I've got the code somewhat working, but it loads to a new page.
I've tried a number of different things that I read on the net, including trying to add "return false" to my showChats function, trying to change the submit to a button and doing "onclick", but it's still not working, always loads a new page. Any ideas on how to solve this?
Thanks in advance. Here's the code:
<script>
counter = 0;
//Array containing initial elements.
var chats = [];
function show_array(array) {
array[counter] = document.getElementById("chatlet").value;
for (x = 0; x < array.length; x++){
document.write(array[x] + "<br/>");
}
counter++;
}
</script>
<form action="agenda2.jsp" method="get" onsubmit="show_array(chats)" >
<p>
<textarea id="chatlet" rows="10" cols="30"></textarea>
</p>
<input type="submit" value="Send Chat">
</form>
</body>
</html>

You need to add return keyword with onsubmit like onsubmit="return show_array(chats)" and then return false in the JS function.
Code:
<form action="agenda2.jsp" method="get" onsubmit="return show_array(chats)" >
JS
counter = 0;
var chats = [];
function show_array(array) {
array[counter] = document.getElementById("chatlet").value;
for (x = 0; x < array.length; x++) {
document.write(array[x] + "<br/>");
}
counter++;
return false;
}
DEMO

Using query you could do below
$('form').submit(function (e) {
e.preventDefault();
$.ajax({
type: "POST",
url: $(this).attr('action'),
data: 'get form data',
success: function (res) {
// handle response here
}
});
});

In the end of your function show_array() you have to add return false; Or in other case you might concider using jQuery and do this:
Give your form a class or id
<form class="myform">
....
</form>
<script>
$("myform").on('submit', function(e) {
e.preventDefault();
});
</script>
Regards!

javascript form validation object

Please i just started learning javascript, In order to build my skill. I gave myself a javascript project to build an object validator.The first method i created is checkEmpty. This method check for empty field. But for reason unknow to me the method don't work.
This is the html form
<form name="myForm">
<input type="text" class="required email" name='fName'/>
<input type="text" class="required number" name="lName"/>
<input type="submit" value="submit" name="submit" id="submit"/>
</form>
This is the javascript that called the validator object
window.onload = function(){
var validate = new FormValidator('myForm');
var submit = document.getElementById('submit');
//this method won't work for internet explorer
submit.addEventListener('click',function(){return checkLogic();},false);
var checkLogic = function(){
validate.checkEmpty('fName');
};
}
This is the javascript object called Formvalidation
function FormValidator(myForm){
//check ur error in stack overflow;
this.myForm = document.myForm;
this.error = '';
if(typeof this.myForm === 'undefined'){
alert('u did not give the form name ');
return;
}
}
//this method will check wheather a field is empty or not
FormValidator.prototype.checkEmpty = function(oEmpty){
var oEmpty = this.myForm.oEmpty;
if(oEmpty.value === '' || oEmpty.value.length === 0){
this.error += "Please Enter a valid Error Message \n";
}
FormValidator.printError(this.error);
};
This method printout the error;
FormValidator.printError = function(oData){
alert(oData);
};

After formatting your code it got a lot easier to find out what went wrong. I assume you are trying to validate the input fields from your html code.
Your code is falling on its nose the first time in line 1 of the method checkEmpty():
FormValidator.prototype.checkEmpty = function(oEmpty){
var oEmpty = this.myForm.oEmpty;
if(oEmpty.value === '' || oEmpty.value.length === 0){
this.error += "Please Enter a valid Error Message \n";
}
FormValidator.printError(this.error);
};
In the first line you are hiding the methods argument oEmpty with the var oEmpty statement from line 1
There are several other issues like overusing methods and members. The following code is probably what you wanted:
1.) index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"/>
<title></title>
</head>
<body>
<form name="myForm">
<input id="fName" name='fName' type="text"/>
<input id="lName" name="lName" type="text"/>
<input id="submit" name="submit" type="submit" value="submit"/>
</form>
<script src="main.js"></script>
</body>
</html>
2.) main.js
function InputFieldValidator(inputFieldName){
this.inputFieldName = inputFieldName;
this.inputField = document.getElementById(this.inputFieldName);
if(this.inputField === 'undefined'){
alert('No input field: ' + this.inputFieldName);
}
}
InputFieldValidator.prototype.validate = function(){
if(this.inputField.value === ''){
alert('Please enter valid text for input field: ' + this.inputFieldName);
}
};
window.onload = function(){
var fNameValidator = new InputFieldValidator('fName'),
lNameValidator = new InputFieldValidator('lName'),
submitButton = document.getElementById('submit');
submitButton.addEventListener('click', function (){
fNameValidator.validate();
lNameValidator.validate();
});
};
If you like you can wrap the input field validators from above easily in a form validator.

This is the right way to define functions this way:
var FormValidator = function(myForm){ /* function body */ };
FormValidator.prototype.checkEmpty = function(oEmpty){ /* function body */ };
Than, after instantiating the object, you can call FormValidator.checkEmpty(value) like you did.

how to add the input values in an array

i just like to ask regarding adding data in a array. But the data which i wanted to put is from a table of input boxes.. Here's the code that i've been practicing to get data:
http://jsfiddle.net/yajeig/4Nr9m/69/
I have an add button that everytime I click that button, it will store data in my_data variable.
i want to produce an output in my variable something like this:
my_data = [ {plank:"1",thickness:"4",width:"6",length:"8",qty:"1",brdFt:"16"}]
and if i would add another data again, it will add in that variable and it be something like this:
my_data = [ {plank:"1",thickness:"4",width:"6",length:"8",qty:"1",brdFt:"16"},
{plank:"2",thickness:"5",width:"6",length:"2",qty:"1",brdFt:"50"}]
the code that i have right now is really bad, so please help.
Currently my output:
1,4,6,4,1

You should be able to iterate over all of the textboxes using the following:
function add(e) {
var obj = {};
$('#addItem input[type="text"]')
.each(function(){obj[this.name] = this.value;});
myItems.push(obj);
}
Where myItems is a global container for your items and #addItem is your form.
Updated jsfiddle.
If you use a form and a submit button then you should be able to implement a non-JavaScript method to add your information so that the site will be accessible to people without JavaScript enabled.

Try this, sorry for modifying your form, but it works well:
HTML:
<form method="post" action="#" id="add_plank_form">
<p><label for="plank_number">Plank number</label>
<p><input type="text" name="plank_number" id="plank_number"/></p>
<p><label for="plank_width">Width</label>
<p><input type="text" name="plank_width" id="plank_width"/></p>
<p><label for="plank_length">Length</label>
<p><input type="text" name="plank_length" id="plank_length"/></p>
<p><label for="plank_thickness">Thickness</label>
<p><input type="text" name="plank_thickness" id="plank_thickness"/></p>
<p><label for="plank_quantity">Quantity</label>
<p><input type="text" name="plank_quantity" id="plank_quantity"/></p>
<p><input type="submit" value="Add"/>
</form>
<p id="add_plank_result"></p>
Javascript:
$(document).ready(function() {
var plank_data = Array();
$('#add_plank_form').submit(function() {
// Checking data
$('#add_plank_form input[type="text"]').each(function() {
if(isNaN(parseInt($(this).val()))) {
return false;
}
});
var added_data = Array();
added_data.push(parseInt($('#plank_number').val()));
added_data.push(parseInt($('#plank_width').val()));
added_data.push(parseInt($('#plank_length').val()));
added_data.push(parseInt($('#plank_thickness').val()));
added_data.push(parseInt($('#plank_quantity').val()));
$('#add_plank_form input[type="text"]').val('');
plank_data.push(added_data);
// alert(JSON.stringify(plank_data));
// compute L x W x F for each plank data
var computed_values = Array();
$('#add_plank_result').html('');
for(var i=0; i<plank_data.length; i++) {
computed_values.push(plank_data[i][1] * plank_data[i][2] * plank_data[i][3] / 12);
$('#add_plank_result').append('<input type="text" name="plank_add[]" value="' + computed_values[i] + '"/>');
}
return false;
});
});

Iterate through all keys, and add the values.
(code written from mind, not tested)
var added = { };
for (var i = 0; i < my_data.length; i ++) {
var json = my_data[i];
for (var key in json) {
if (json.hasOwnProperty(key)) {
if (key in added) {
added[key] += json[key];
} else {
added[key] = json[key];
}
}
}
}

You can use the javascript array push function :
var data = [{plank:"1",thickness:"4",width:"6",length:"8",qty:"1",brdFt:"16"}];
var to_add = [{plank:"2",thickness:"5",width:"6",length:"2",qty:"1",brdFt:"50"}];
data = data.concat(to_add);

Sorry I only glanced at the other solutions.
$(document).ready(function() {
var myData=[];
var myObject = {}
$("input").each(function() {
myObject[this.id]=this.value
});
alert(myObject["plank"])
myData.push(myObject)
});