how to reset the value of a textbox - javascript

I'm making just a simple math learning helper to help me learn javascript. I want to refresh The textbox after a wrong answer(the page refreshes after a right answer to get a new question), but I want the question to be the same if you get it wrong. Here's my code:
<!doctype html>
<body>
<center>
<font size="5">
<form Id="Input">
<input type="text" name="Input">
<input type="button" value="submit" ID="Button">
</form>
<script type="text/javascript">
Button.addEventListener("click", Answer);
var A = Math.floor(Math.random()*11);
var B = Math.floor(Math.random()*11);
var C = A +B;
var Input = document.getElementById('Input');
document.write(A + "+" + B + "=");
function Answer() {
if(Input.Input.value == C) {
alert("correct!");
window.location.reload();
} else {
alert("incorrect!");
document.getElementById('txtField').value='new value here'
}
}
</script>
</body>
</html>

You just need to give the txtField id to the text input here is a working fiddle http://jsfiddle.net/eFf27/
<input id="txtField" type="text" name="Input">

You forgot to add an ID to your text box.
<!doctype html>
<body>
<center>
<font size="5">
<form Id="Input">
<input id="txtField" type="text" name="Input">
<input type="button" value="submit" ID="Button">
</form>
<script type="text/javascript">
Button.addEventListener("click", Answer);
var A = Math.floor(Math.random()*11);
var B = Math.floor(Math.random()*11);
var C = A +B;
var Input = document.getElementById('Input');
document.write(A + "+" + B + "=");
function Answer()
{
if(Input.Input.value == C)
{
alert("correct!");
window.location.reload();
}
else
{
alert("incorrect!");
document.getElementById('txtField').value='new value here'
}
}
</script>
</body>
</html>

Related

This calculator using form submission to satisfy variables isn't working

I am attempting to make a calculator in order to... well, calculate something. Anyway, I am trying to make 4 variables be set too 4 user inputs by using form submission. However, no matter what I do, I can't get the variables to get set. Help would be appreciated!
<!DOCTYPEhtml>
<html>
<head>
<title>NatHisCalc</title>
</head>
<body>
<h1><center><b><p>Test</p></b></center></h1>
<center><b><p id='output'>loading...</p></b></center>
<center><b><p id='output2'>loading...</p></b></center>
<center><b><p id='output3'>loading...</p></b></center>
<center><b><p id='output4'>loading...</p></b></center>
<form id="a" action="/action_page.php">
Input X <input type="number" name="x"><br><br>
<input type="button" onclick="calc()" value="Submit">
</form>
<form id="a" action="/action_page.php">
Input X <input type="number" name="y"><br><br>
<input type="button" onclick="calc()" value="Submit">
</form>
<form id="a" action="/action_page.php">
Input X <input type="number" name="a"><br><br>
<input type="button" onclick="calc()" value="Submit">
</form>
<form id="a" action="/action_page.php">
Input X <input type="number" name="b"><br><br>
<input type="button" onclick="calc()" value="Submit">
</form>
<script>
function calc() {
var x = document.getElementById("x").submit();
var y = document.getElementById("y").submit();
var a = document.getElementById("a").submit();
var b = document.getElementById("b").submit();
var u = (0.101*(y/100))*(480000*(a/100))
var j = (0.581*(x/100))*(120000*(b/100))
if (x > 150 || x < 50) {
window.alert('Hold on... Those inputs will result in an unreasonable output. You can click ');
}
var preresult = j + u;
if (preresult < 177000) {
document.getElementById('output').innerHTML = 'Test';
} else {
document.getElementById('output').innerHTML = 'Test1';
}
if (u > 179999) {
document.getElementById('output').innerHTML = 'Test2';
}
document.getElementById('output2').innerHTML = 'Test3' + j;
document.getElementById('output3').innerHTML = 'Test4 ' + u;
document.getElementById('output4').innerHTML = 'Test5 ' + preresult;
}
</script>
</body>
</html>
Looked into your code, it seems that you have made things way too much complicated that it should be. First of all, you don't call submit function on the input to get the value of it. If you want to get the value of x then you just access the value property like this document.getElementById("x").value. Secondly, you really don't need four buttons, all you need to do is ONE button that submits the form and adding required on input fields makes the browser not submit the form until all forms are filled. Last of all, id attribute needs to be unique across your page. You have both form and input field as id a which is unacceptable. It will show no error but get you in sorts of trouble. You can see what I did here, where I prevented the form from being submitted upon the button click and simply called the calc function to perform the calculation.
<!DOCTYPEhtml>
<html>
<head>
<title>NatHisCalc</title>
</head>
<body>
<h1><center><b><p>Test</p></b></center></h1>
<center><b><p id='output'>loading...</p></b></center>
<center><b><p id='output2'>loading...</p></b></center>
<center><b><p id='output3'>loading...</p></b></center>
<center><b><p id='output4'>loading...</p></b></center>
<form onsubmit="event.preventDefault(); calc();" action="/action_page.php">
Input X <input type="number" id="x" required><br><br>
Input Y <input type="number" id="y" required><br><br>
Input A <input type="number" id="a" required><br><br>
Input B <input type="number" id="b" required><br><br>
<input type="submit" value="Submit">
</form>
<script>
function calc() {
var x = document.getElementById("x").value;
var y = document.getElementById("y").value;
var a = document.getElementById("a").value;
var b = document.getElementById("b").value;
var u = (0.101*(y/100))*(480000*(a/100))
var j = (0.581*(x/100))*(120000*(b/100))
if (x > 150 || x < 50) {
window.alert('Hold on... Those inputs will result in an unreasonable output. You can click ');
}
var preresult = j + u;
if (preresult < 177000) {
document.getElementById('output').innerHTML = 'Test';
} else {
document.getElementById('output').innerHTML = 'Test1';
}
if (u > 179999) {
document.getElementById('output').innerHTML = 'Test2';
}
document.getElementById('output2').innerHTML = 'Test3' + j;
document.getElementById('output3').innerHTML = 'Test4 ' + u;
document.getElementById('output4').innerHTML = 'Test5 ' + preresult;
}
</script>
</body>
</html>

I am trying to convert Fahrenheit to Celsius but it's not working what am i doing wrong? - Javascript (needs to have a form and a clear button)

<html>
<head>
<title>
Form
</title>
</head>
<body>
<script type="text/javascript">
function calculate (form)
{
cel = fah * 0.5555 - 32;
document.getElementById("finish").innerHTML = cel;
}
</script>
<form name="myform" action="" method="get"> Turn Fahrenheit to Celsius! <br>
<input type="number" name="fah">
<input type="button" name="button" value="calculate" onClick="calculate(this.form)">
<button type="reset" value="Reset">Reset</button>
</form>
<p id="finish">°C</p>
</body>
</html>
Edit1: Moved the inner.HTML into the Function
So the reset button is the only thing that works. Is it possible to calculate the math this way?
You asked a question on how to create a pizza form a while ago and you deleted it soon as it was down voted a few times.
The point to note here is, it is okay if a few people dislike your question. You've joined StackExchange not to gain points but to learn a few things. Your question could be helpful to a lot of others out there in this world. So here it is the answer to your pizza question
<html>
<body>
<p>A pizza is 13 dollars with no toppings.</p>
<form action="form_action.asp">
<input type="checkbox" name="pizza" value="Pepperoni" id="pep">Pepperoni + 5$<br>
<input type="checkbox" name="pizza" value="Cheese" id="che">Cheese + 4$<br>
<br>
<input type="button" onclick="myFunction()" value="Send order">
<input type="button" onclick="cost()" value="Get cost">
<br><br>
<input type="text" id="order" size="50">
</form>
<script>
function myFunction() {
var pizza = document.forms[0];
var txt = "";
var i;
for (i = 0; i < pizza.length; i++) {
if (pizza[i].checked) {
txt = txt + pizza[i].value + " ";
}
}
document.getElementById("order").value = "You ordered a pizza with: " + txt;
}
function cost() {
var pep = 5;
var che = 4;
var pizza = 13;
var total = 0;
if (document.getElementById("pep").checked === true) {
total += pep;
}
if (document.getElementById("che").checked === true) {
total += che;
}
document.getElementById("order").value = "The cost is : " + total;
}
</script>
</body>
</html>
Thanks. I hope this helps you.
Adeno Fixed it by declaring what fah was. you can also see your errors with f12.
https://stackoverflow.com/users/965051/adeneo
<html>
<head>
<title>
Form
</title>
</head>
<body>
<script type="text/javascript">
function calculate(form) {
var cel = (document.getElementById("fah").value -32) * 5 / 9;
document.getElementById("finish").innerHTML = cel;
}
</script>
<form name="myform" action="" method="get"> Turn Fahrenheit to Celsius!
<br>
<input type="number" name="fah" id="fah">
<input type="button" name="button" value="calculate" onClick="calculate(this.form)">
<button type="reset" value="Reset">Reset</button>
</form>
<p id="finish">°C</p>
</body>
You never get the value from the input type = "number"
Try this
<html>
<head>
<meta charset="utf-8">
<title>Untitled Document</title>
<script>
function calculate()
{
var fah = document.getElementById('fah').value;
var cel = parseFloat(fah * 0.5555 - 32);
document.getElementById("finish").innerHTML = cel;
}
</script>
</head>
<body>
<form>
Turn Fahrenheit to Celsius! <br>
<input type="text" name="fah" id="fah">
<input type="button" name="button" value="calculate" onClick="calculate()">
<button type="reset" value="Reset">Reset</button>
</form>
<p id="finish">°C</p>
</body>
</html>
Couple things: You need to set the innerhtml from within the function because the variable is in the function. Or you could have declared the variable outside the function first like var fah = "" then the function. But since you declared it in the function only the function can see it. So i moved the innerhtml set into the function.
Also, javascript likes to use id's not name = "fah" You can call an element by name but id is easier.
i rounded it to integer. you would get 9 decimals your way.
Lastly, innerhtml set clears all the html so you would lose the °C the way you had it.
<html>
<head>
<title>
Form
</title>
</head>
<body>
<script type="text/javascript">
function calculate (form)
{
var fah = this.fah.value;
cel = Math.round((fah-32) / 1.8);
document.getElementById("finish").innerHTML = cel+"°C";
}
</script>
<form name="myform" action="" method="get"> Turn Fahrenheit to Celsius! <br>
<input type="number" name="fah" id = "fah">
<input type="button" name="button" value="calculate" onClick="calculate(this.form)">
<button type="reset" value="Reset">Reset</button>
</form>
<p id="finish"></p>
</body>
</html>

Getting two strings as input from user, not the button value

I have this code:
<!DOCTYPE html>
<html>
<body>
<form id="frm1" action="form_action.asp">
First name: <input type="text" name="fname" value="Donald"><br>
Last name: <input type="text" name="lname" value="Duck"><br><br>
<input type="submit" value="Submit">
</form>
<p>Click "Try it" to display the value of each element in the form.</p>
<button onclick="myFunction()">Try it</button>
<p id="demo"></p>
<script>
function myFunction() {
var x = document.getElementById("frm1");
var text = "";
var i;
for (i = 0; i < x.length ;i++) {
if(x.elements[i].value)
text += x.elements[i].value + "<br>";
}
document.getElementById("demo").innerHTML = text;
}
</script>
</body>
</html>
Which will treat "Submit" string from the Submit button as an input string to. Obviously, assuming that the user won't input "Submit", I could hardcode-check if the value is "Submit" and skip it.
Isn't there any other way?
I could hardcode-check if the value is "Submit" and skip it.
Checking the value doesn't work because the user might actually type the word "Submit".
You can test the type of the elements:
if (x.elements[i].type === "text") { ... }
Or you can just select the text elements directly using the querySelectorAll() method:
function myFunction() {
var x = document.querySelectorAll("#frm1 input[type='text']");
var text = "";
var i;
for (i = 0; i < x.length ;i++) {
text += x[i].value + "<br>";
}
document.getElementById("demo").innerHTML = text;
}
<form id="frm1" action="form_action.asp">
First name: <input type="text" name="fname" value="Donald"><br>
Last name: <input type="text" name="lname" value="Duck"><br><br>
<input type="submit" value="Submit">
</form>
<p>Click "Try it" to display the value of each element in the form.</p>
<button onclick="myFunction()">Try it</button>
<p id="demo"></p>
You can check the element's type (x.elements[i].type === 'text'):
<!DOCTYPE html>
<html>
<body>
<form id="frm1" action="form_action.asp">
First name: <input type="text" name="fname" value="Donald"><br>
Last name: <input type="text" name="lname" value="Duck"><br><br>
<input type="submit" value="Submit">
</form>
<p>Click "Try it" to display the value of each element in the form.</p>
<button onclick="myFunction()">Try it</button>
<p id="demo"></p>
<script>
function myFunction() {
var x = document.getElementById("frm1");
var text = "";
var i;
for (i = 0; i < x.length ;i++) {
if(x.elements[i].value && x.elements[i].type === 'text')
text += x.elements[i].value + "<br>";
}
document.getElementById("demo").innerHTML = text;
}
</script>
</body>
</html>
Display just elements with a name:
for (i = 0; i < x.length ;i++) {
if(x.elements[i].value && x.elements[i].name)
text += x.elements[i].value + "<br>";
}
Possibly more useful than only selecting text inputs since you don't have to recode if you have other types - plus, reinforces that these are the items that would get sent during form submission.
And because I was bored:
function myFunction() {
document.getElementById("demo").innerHTML =
Array.prototype.slice.call(document.querySelectorAll("#frm1 input[name]"))
.reduce( ( prev, curr ) =>
{ return prev + curr.value + "<br />"; }, "");
}
document.addEventListener( "DOMContentLoaded",
function() {
document.getElementById("button").addEventListener("click", myFunction, false);
}, false );
<body>
<form id="frm1" action="form_action.asp">
First name: <input type="text" name="fname" value="Donald"><br>
Last name: <input type="text" name="lname" value="Duck"><br><br>
<input type="submit" value="Submit">
</form>
<p>Click "Try it" to display the value of each element in the form.</p>
<button id="button">Try it</button>
<p id="demo"></p>
</body>

Putting all the output in a specific textbox in a while loop in JavaScript

So all I want here to happen is that how can I put all the given output in the answer textbox.
UPDATE
<html>
<body>
<script type="text/javascript">
function myFunction() {
var x = parseInt(document.f1.n1.value);
var y = parseInt(document.f1.n2.value);
if(x>=y) {
document.write("Invalid");
}
while (x<y)
{
document.write(x)
x=x+1;
}
}
</script>
<form name=f1 onsubmit="return false">
First no. <input type="text" name="n1">
Second no. <input type="text" name="n2">
Answer: <input type="text" name="ans" disabled>
<input type="submit" onClick="myFunction()">
</form>
</body>
</html>
Thank you in advance
You can do something like this:
Give answer input an id:
<input id="answerTextBox" type="text" name="ans" disabled>
After while loop populate answer textbox:
while (x>y)
{
document.getElementById("answerTextBox").value += ("" + x);
x=x+1;
}
This will put x and y in your answer textbox.
UPDATE******
<html>
<body>
<script type="text/javascript">
function myFunction() {
document.getElementById("answerTextBox").value = "";
var x = parseInt(document.getElementById("n1").value);
var y = parseInt(document.getElementById("n2").value);
if(x >= y)
{
document.getElementById("answerTextBox").value = "Invalid Input";
}
while (x < y)
{
document.getElementById("answerTextBox").value += ("" + x);
x=x+1;
}
}
</script>
First no. <input type="text" name="n1" id="n1">
Second no. <input type="text" name="n2" id="n2">
Answer: <input id="answerTextBox" type="text" name="ans" readonly>
<input type="button" onClick="myFunction()">
</form>
</body>
</html>
UPDATE for exponential************************
<html>
<body>
<script type="text/javascript">
function myFunction() {
document.getElementById("answerTextBox").value = "";
var x = parseInt(document.getElementById("n1").value);
var y = x;
var answer = 1;
for(var i = 0; i < y; i++)
{
answer = answer * x;
}
document.getElementById("answerTextBox").value = answer;
}
</script>
Enter Number: <input type="text" name="n1" id="n1">
Answer: <input id="answerTextBox" type="text" name="ans" readonly>
<input type="button" value="Submit" onClick="myFunction()">
</form>
</body>
</html>
UPDATE Add Exponents*****************
<html>
<body>
<script type="text/javascript">
function myFunction() {
document.getElementById("answerTextBox").value = "";
var x = parseInt(document.getElementById("n1").value);
var y = parseInt(document.getElementById("n2").value);
var answer = 0;
for(var i = 0; i <= y; i++)
{
answer = answer + Math.pow(x, i);
}
document.getElementById("answerTextBox").value = answer;
}
</script>
Enter Base Number: <input type="text" name="n1" id="n1">
Enter Highest Exponent: <input type="text" name="n2" id="n2">
Answer: <input id="answerTextBox" type="text" name="ans" readonly>
<input type="button" value="Submit" onClick="myFunction()">
</form>
</body>
</html>
<html>
<body>
The number inserted in the textbox is the number of exponent it will generate. The sample is 3. 3X3X3 is 27. <br>
<script type="text/javascript">
function myFunction() {
var x = document.f1.n1.value;
while(x<27)
{
x=x*3;
}
document.write(x)
}
</script>
<form name="f1" onsubmit="return false">
First no. <input type="text"name="n1" value=3 disabled>
<input type="submit" onClick="myFunction()">
</form>
</body>
</html>
Update: The Exponent in any number.

How to show input (name + value) in textarea?

I'm working on this project where I need to have the value of a textarea change when one of the input values in the same form changes.
HTML:
<form id="form" action="" method="">
<textarea readonly class="overview"></textarea>
<input type="text" class="add" name="product1" />
<input type="text" class="add" name="product2" />
<input type="text" class="add" name="product3" />
<input type="text" class="add" name="product4" />
</form>
The customer is allowed to change the input.class.
The textarea-value should change whenever one of the inputs changes.
The textarea should show something like:
3 x product1
1 x product3
4 x product4
Anybody got an idea?
Thanks in advance,
Joel
<textarea readonly class="overview" id="mytxtarea"></textarea>
$("#product1").blur(function(){
if($("#product1").val()!='')
{
$("#mytxtarea").val('test value');
}
});
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Test</title>
<script type="text/javascript" src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
<script type="text/javascript">
$(document).ready(function(){
$('#form .add').on('keyup', function(){
console.log('test');
var string1 = $('#form .product1').val() + ' x product1\n';
var string2 = $('#form .product2').val() + ' x product2\n';
var string3 = $('#form .product3').val() + ' x product3\n';
var string4 = $('#form .product4').val() + ' x product4';
$('#form textarea').val(string1 + string2 + string3 + string4);
});
});
</script>
</head>
<body>
<form id="form" action="" method="">
<textarea readonly class="overview"></textarea>
<input type="text" class="add product1" name="product1" />
<input type="text" class="add product2" name="product2" />
<input type="text" class="add product3" name="product3" />
<input type="text" class="add product4" name="product4" />
</form>
</body>
</html>
$(".add").keyup(function () {
var app=""
$(".add").each(function () {
if( $(this).val() ) {
var value=$(this).val();
var name=$(this).attr('name');
app +=value+"*"+name+ "\n" ;
}
});
$(".overview").text(app);
});
Watch this.
Hope this will give you some solution.
This will do what you want...
$("input.add").keyup(function() {
var msg = "";
$("input.add").each( function() {
if( $(this).val() ) {
msg += $(this).val() + "x " + $(this).attr("name") + "\n";
}
});
$("textarea.overview").text(msg)
});
I used this with your HTML here: http://jsfiddle.net/XYXpp/
$('input').keyup(function () {
var inputedValue = $(this).val();
var name = $(this).attr('name');
$(".overview").text(inputedValue+name);
});
var fd = new FormData()
fd.append('csrfmiddlewaretoken', document.getElementsByName('csrfmiddlewaretoken')[0].value)
fd.append('field_name', $("input[name='field_name']").serialize())
will return
['field_name=9&field_name=15&field_name=10']
you will then have to parse the info in your view

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