How to print javascript while loop result in html textarea? - javascript

Prints '2 x 10 = 20' but not the whole table when the input is 2. I tried various means. But the result is same.
No error. Just like to print the whole multiplication table.
function loop() {
var i = 1;
var x = document.getElementById("num").value;
//document.getElementById("result").value = result;
while (i <= 10) {
document.getElementById("result").value = x + " x " + i + " = " + i * x;
i++;
}
}
<h1>While loop: </h1>
<p>The while loop keeps repeating an action until an associated condition returns false.</p>
<img src="images/loop.jpg" /><br/>
<img src="images/loop2.jpg" /><br/>
<body>
<p>JavaScripts Runs:</p>
<script src="while_1loop.js">
</script><br/> What number table would you like to have?<input type="number" name="" id="num" /><br>
<button type="button" onclick="loop()" ;>Start</button><br>
<textarea rows="12" cols="15" id="result" readonly>
</textarea><br/>

You are always changing the value of 'result' rather than adding to it:
function loop() {
var i = 1;
var x = document.getElementById("num").value;
//document.getElementById("result").value = result;
while (i <= 10) {
var result = document.getElementById("result");
var sum = document.createTextNode(x + " x " + i + " = " + i * x + "\n");
result.appendChild(sum);
i++;
}
}
<h1>While loop: </h1>
<p>The while loop keeps repeating an action until an associated condition returns false.</p>
<img src="images/loop.jpg" /><br/>
<img src="images/loop2.jpg" /><br/>
<body>
<p>JavaScripts Runs:</p>
<script src="while_1loop.js">
</script><br/> What number table would you like to have?<input type="number" name="" id="num" /><br>
<button type="button" onclick="loop()" ;>Start</button><br>
<textarea rows="12" cols="15" id="result" readonly>
</textarea><br/>

If I understand what you mean,
You rewrite whole textarea with this code:
document.getElementById("result").value = x + " x " + i + " = " + i * x;
but you need add new result after older results. Something like this:
var oldValue = document.getElementById("result").value;
var result = x + " x " + i + " = " + i * x;
document.getElementById("result").value = oldValue + '\n' + result;

Related

Trying to get the HTML displayed to change every time a new button is clicked with jquery

let table = 6;
let i = 1;
$(function() {
let $newOperatorButton = $('button');
$newOperatorButton.on('click', function math(){
let msgOperator = '';
let expression;
let operator = $(this).attr("value");
if(operator === '+'){
msgOperator = ' + ';
expression = (table + i);
while(i < 11){
msg += table + msgOperator + i + ' = ' + (table + i) + '<br />';
i++;
}
} else if (operator === '-') {
msgOperator = ' - ';
expression = (table - i);
while(i < 11){
msg += table + msgOperator + i + ' = ' + (table - i) + '<br />';
i++;
}
some code missing but it adds multiplication and division
let el = document.getElementById('blackboard');
el.innerHTML = msg;
}
);
});
This code is inside the body tag in my index.html
<section id="page">
<section id="blackboard"></section>
</section>
<form id="operator">
<button name="add" type="button" value="+">+</button>
<button name="subtract" type="button" value="-">-</button>
<button name="multiply" type="button" value="x">x</button>
<button name="division" type="button" value="/">/</button>
</form>
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script src="/index.js"></script>
I have it so it prints out a table with 10 numbers depending on the button clicked. For ex. table = 6 and i = 1 is 6+1=7.... 6+10=16
You need an if statement at the end that reset your equations and variables.
after you've run your equation "i" is still equal to 11 so it never passes into the while loops again, you also need to empty your message so it doesn't keep adding addition text to your existing text.
$("#blackboard").html(msg)
if (i == 11) {
i = 1
msg = ""
}

Simple Calculator Test

When I process my code in the browser all I get is this:
I use the following code that does not work as intended:
function compute() {
p=document.getElementById("principal").value;
r=document.getElementById("rate").value;
n=document.getElementById("years").value;
result=document.getElementById("result");
result.innerHTML="If you deposit " + p + ",";
result.innerHTML="at an interest rate of " + r + ".";
result.innerHTML="in the year " + (newDate - n);
result.innerHTML="You will receive an amount of " + (p*n*r/100) + ",";
}
With a small number of modifications, the compute function should work very well.
The changes:
Ensure all our input values are converted to numbers.
Create a result output element (id="result") to show the results.
Append output to result string, then assign this to result element innerHTML.
Create getFutureValue function to get total amount after n years.
function getFutureValue(principal, interestRatePercent, termYears) {
return principal*Math.pow(1 + interestRatePercent/100, termYears);
}
function showResult(result) {
document.getElementById("result").innerHTML = result;
}
function compute() {
// Ensure all values are _numbers_
p = Number(document.getElementById("principal").value);
r = Number(document.getElementById("rate").value);
n = Number(document.getElementById("years").value);
const newDate = new Date();
newDate.setFullYear(newDate.getFullYear() + n);
let result = "If you deposit $" + p + ", ";
result += "at an interest rate of " + r + "%, ";
result += "in the year " + (newDate.getFullYear());
result += ", you will receive an amount of $" + getFutureValue(p, r, n).toFixed(2);
showResult(result);
}
compute()
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap#5.0.2/dist/css/bootstrap.min.css">
<form class="p-3">
<div class="mb-3">
<label for="principal" class="form-label" >Amount</label>
<input type="number" class="form-control" id="principal" value="1000">
</div>
<div class="mb-3">
<label for="rate" class="form-label">Interest Rate</label>
<input type="number" class="form-control" id="rate" value="3.5">
</div>
<div class="mb-3">
<label for="years" class="form-label">No. of Years</label>
<input type="number" class="form-control" id="years" value="25">
</div>
<button type="button" class="btn btn-primary" onclick="compute()">Compute Interest</button>
<div class="mb-3 mt-4">
<label for="result" class="form-label">Result</label>
<p id="result"></p>
</div>
</form>
Try this
function getresult() {
var result = '';
result += 'If you deposit:P' +
'at an interest rate of R' +
'in the year Y' +
'You will receive an amount of R';
document.getElementById("result").innerHTML = result;
}

My internal JavaScript for my Kelvin/Fahrenheit Converter is not working

I put my JavaScript inside tags instead of externally(because external files weren't working) and for some reason my code is not running.
Just to be sure that it wasn't a problem with the code itself, I put a simple alert before all the code and nothing popped up.
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<h1>Fahrenheit/Kelvin Converter</h1>
<div id = "first" class = "oneof">
<h2>Kelvin to Fahrenheit</h2>
<input type = "text" placeholder = "Enter Kelvin here" id = "kinput">
<button id = "ksubmit">Submit Kelvin</button><br><br>
<textarea id = "fpopup" rows = "5" cols = "50"></textarea>
</div>
<div id = "second" class = "oneof">
<h2>Fahrenheit to Kelvin</h2>
<input type = "text" placeholder = "Enter Fahrenheit here" id = "finput">
<button id = "fsubmit">Submit Fahrenheit</button><br><br>
<textarea id = "kpopup" rows = "5" cols = "50"></textarea>
</div>
<script>
alert("Hello World"); //Testing JS
if(6==6){
alert("ua");
}
function ftok(f){
k = (f − 32) * 5/9 + 273.15;
return k;
}
function ktof(k){
f = (K − 273.15) * 9/5 + 32;
return f;
}
document.getElementById("ksubmit").onclick = function() {
document.getElementById("fpopup").value = document.getElementById("kinput").value + " degrees Kelvin is " + ktof(Number(document.getElementById("kinput").value)) + " degrees Fahrenheit"
}
document.getElementById("fsubmit").onclick = function() {
document.getElementById("kpopup").value = document.getElementById("finput").value + " degrees Fahrenheit is " + ftok(Number(document.getElementById("finput").value)) + " degrees Kelvin"
}
</script>
</body>
</html>
You can use DOMContentLoaded function to make sure the HTML is ready and parsed properly. Also you have some syntax errors which i have fixed as well.
Also, You were using some weird minus and multiplication characters.
The DOMContentLoaded event fires when the initial HTML document has been completely loaded and parsed
Your code is now working as expected.
Live Demo:
<!DOCTYPE html>
<html>
<head>
</head>
<body>
<h1>Fahrenheit/Kelvin Converter</h1>
<div id="first" class="oneof">
<h2>Kelvin to Fahrenheit</h2>
<input type="text" placeholder="Enter Kelvin here" id="kinput">
<button id="ksubmit">Submit Kelvin</button><br><br>
<textarea id="fpopup" rows="5" cols="50"></textarea>
</div>
<div id="second" class="oneof">
<h2>Fahrenheit to Kelvin</h2>
<input type="text" placeholder="Enter Fahrenheit here" id="finput">
<button id="fsubmit">Submit Fahrenheit</button><br><br>
<textarea id="kpopup" rows="5" cols="50"></textarea>
</div>
<script>
window.addEventListener('DOMContentLoaded', (event) => {
if (6 == 6) {
alert("ua");
}
function ftok(f) {
var k = (f - 32) * 5 / 9 + 273.15;
return k;
}
function ktof(k) {
var f = (k - 273.15) * 9 / 5 + 32;
return f;
}
document.getElementById("ksubmit").onclick = function() {
document.getElementById("fpopup").value = document.getElementById("kinput").value + " degrees Kelvin is " + ktof(Number(document.getElementById("kinput").value)) + " degrees Fahrenheit"
}
document.getElementById("fsubmit").onclick = function() {
document.getElementById("kpopup").value = document.getElementById("finput").value + " degrees Fahrenheit is " + ftok(Number(document.getElementById("finput").value)) + " degrees Kelvin"
}
})
</script>
</body>
</html>

Unable to generate a multiplication table with user input in JavaScript

I have a page which prompts the user to enter a positive integer from 1 to 9, then the javascript code will generate a multiplication table from the input value all the way to 9. I am getting an error in which I cannot retrieve the value and do a multiplication with it.
function timesTable()
{
var values = document.getElementById('value1');
var showTables = '';
for (var i=1; i<9; i++) {
showTables += values + " x " + i +" = "+ values*i + "\n";
}
var p_tables = document.getElementById('tables').innerHTML = showTables;
}
<label>Enter an integer from 1 to 9 : </label>
<input type="text" size=20 id=value1 name="value">
<button onclick="timesTable()">Generate times table</button><br> <br>
<p id="tables"></p>
Expected result:
You have to take the value of the element not the element itself
var values = document.getElementById('value1').value;
function timesTable()
{
var values = document.getElementById('value1').value;
var showTables = '';
for (var i=1; i<9; i++) {
showTables += values + " x " + i +" = "+ values*i + "<br>";
}
var p_tables = document.getElementById('tables').innerHTML = showTables;
}
<label>Enter an integer from 1 to 9 : </label>
<input type="text" size=20 id=value1 name="value">
<button onclick="timesTable()">Generate times table</button><br> <br>
<p id="tables"></p>
You are trying to multiply the element itself. What you actually want is the value.
function timesTable()
{
var values = document.getElementById('value1').value;
var showTables = '';
for (var i=1; i<9; i++) {
showTables += values + " x " + i +" = "+ values*i + "\n";
}
var p_tables = document.getElementById('tables').innerHTML = showTables;
}
<label>Enter an integer from 1 to 9 : </label>
<input type="text" size=20 id=value1 name="value">
<button onclick="timesTable()">Generate times table</button><br> <br>
<p id="tables"></p>
the javascript line in which you are trying to find value, is wrong as it will return the whole DOM and it's attributes and property.
You just have to find it's value, replace you line
var values = document.getElementById('value1');
with
var values = document.getElementById('value1').value;
This does what you want.
Note that if the user enters something unexpected, it may still fail. You can use an input of type="number" to require an integer (at least in some browsers.)
const userValue = document.getElementById("value1").value;
const p_tables = document.getElementById("tables");
let outputHtml = "";
for(let i = 1; i < 10; i++){
outputHtml += userValue + " x " + i + " = " + userValue * i + "<br/>";
}
p_tables.innerHTML = outputHtml;
you are using input field as text for table generation its better to use Number as input type and to get the value of input field you have to use value function as used in above code and for line break use
<\br>(please ignore '\').
function timesTable()
{
var values = document.getElementById('value1').value;
var showTables = '';
for (var i=1; i<=9; i++) {
showTables += values + " x " + i +" = "+ values*i + "<br>";
}
document.getElementById('tables').innerHTML = showTables;
}
<label>Enter an integer from 1 to 9 : </label>
<input type="Number" size=20 id=value1 name="value">
<button onclick="timesTable()">Generate times table</button><br> <br>
<p id="tables"></p>

Increment Serial Numbers and calculate - javascript

Our company has a client that requires a specific checksum on their bar codes. I've come up with the following which allows the user to enter the distributor part number, our part number and our serial number. Right now, when you click save, it will calculate correctly for the bar code with the checksum. NOW, we have added a quantity box so that we can print x number of barcodes with our serial number incrementing by 1. (i.e. 1st serial number is 000001, next will be 000002 and so on). What I've been trying to do for the last week is alter this code so the user can input the part numbers and sn, and it will calculate each bar code up to the quantity.
This is what we would like to have:
If user enters part numbers, first serial number and quantity then clicks "Save" this should be the result. At present, this can only be achieved by entering each serial number and clicking save
*note: while the quantity can be entered, the actual value has not been used in my code...yet
So, to achieve this, I need to find a way to increment the serial numbers without dropping off the leading zeros but maintaining the length of qty.length.
I also need to figure out how to loop each new serial number through with part numbers to get the correct checksum for the bar code. After a week of staring at this, I'm hoping some fresh and experienced eyes can assist. Here is my code.
<?xml version="1.0" encoding="UTF-8"?>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Capture Form Fields to CSV</title>
<script type="text/javascript">
<!--
function saveValues() {
var frm = document.form1;
var str = frm.text1.value + frm.text2.value + frm.text3.value;
var dpn = frm.text1.value;
var wpn = frm.text2.value;
var wsn = frm.text3.value;
var strArray = str.split("");
var calcArray = strArray;
var total =0;
for (var i = 0; i < str.length; i++)
strArray[i] = strArray[i].charCodeAt(0);
for (var i = 0; i < strArray.length; i++){
if (strArray[i] >= 65 && strArray[i] <= 90){
calcArray[i] = (strArray[i] - 64) * (i+1)
}
else if (strArray[i] >=97 && strArray[i] <=122) {
calcArray[i] = (strArray[i] - 96) * (i+1)
}
else if (strArray[i] >=48 && strArray[i] <=57) {
calcArray[i] = (strArray[i] - 48) * (i+1)
}
else {
calcArray[i] = 1 * (i+1)
}
}
for (var i in calcArray){
total += calcArray[i];}
var mod2 = str.length - (2*(Math.floor(str.length/2)));
var mod10 = (total + mod2) - (10*(Math.floor((total + mod2)/10))) ;
var chk = mod10;
var record = ""
+ dpn + "," + wpn + "," + wsn + "," +dpn + "~" + wpn + "~" + wsn + "~" + chk + "\n";
frm.textarea1.value += record;
}
function clearText() {
document.form1.textarea1.value = "";P
form1.text1.value = "";
form1.text2.value = "";
form1.text3.value = "";
}
function csvSave() {
var a = document.createElement('a');
with (a) {
href='data:text/csv;base64,' + btoa(document.getElementById('textarea1').value);
download='csvfile.csv';
}
document.body.appendChild(a);
a.click();
document.body.removeChild(a);
}
//-->
</script>
</head>
<body>
<h1>Capture Form Fields to CSV</h1>
<form name="form1" >
<p>
Distributor Part Number: <input name="text1" type="text" value="GDM1301" /><br />
Our Part Number: <input name="text2" type="text" value="PCBDM160"/><br />
Our Serial Number: <input name="text3" type="text" value="000001"/><br />
Label Quantity: <input name="qty" type="text" value="3"/>
</p>
<p>
<input name="save" type="button" value="Save"
onclick="saveValues(); return false"/>
 
<input name="clear" type="button" value="Clear"
onclick="clearText(); return false"/>
<button onclick="csvSave()">CSV</button>
</p>
<p>
<i>Click 'Save' to add content</i><br />
<textarea id="textarea1" cols="80" rows="20"></textarea>
</p>
</form>
</body>
</html>

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