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textarea isn't reading input that I have made [duplicate]

This question already has answers here:
Why does jQuery or a DOM method such as getElementById not find the element?
(6 answers)
Closed 1 year ago.
So no matter what I change if I input anything in the textarea it is not reading anything from the form.
I needed it to be able to have input and not just change the default message of the textarea. If there is any other error in my code please help me by correcting me. And this is only purely html and javascript.
function manage(txt) {
var input = document.getElementById('replace');
if (txt.value != '') {
input.disabled = false;
}
else {
input.disabled = true;
}
}
function findReplace() {
var str = document.getElementById("message").innerHTML;
var find = document.getElementById("find").value;
var replace = document.getElementById("replace").value;
var res = str.replaceAll(find, replace);
document.getElementById("message").innerHTML = res;
}
function Counter(str) {
var str = document.getElementById("message").innerHTML;
var msg = str.split(" ");
var element = document.getElementById("replace").value;
var count = 0;
for ( var i = 0; i < msg.length; i++)
{
if (element == msg[i])
{
count++;
i++;
} else
{
i++;
}
document.getElementById("demo").innerHTML = "Number of replacement: " + count;
}
}
<!-- Message -->
<label for="message">Message: </label><br>
<textarea required type = "text" id="message" name = "message" rows="3" cols="20" method = "post">Hello testing</textarea><br>
<!-- Finding box -->
<label for="find">Find: </label><br>
<input type="text" id="find" name="find" onkeyup = "manage(this)"><br>
<!-- Replace box -->
<label for="replace">Replace with: </label><br>
<input disabled type="text" id="replace" name="replace">
<!--Submit button -->
<input type="button" value="find and replace" onclick ="findReplace(); Counter();">

Try value instead of innerHTML for textarea control.
function findReplace() {
var str = document.getElementById("message").value; //use value here
console.log(str)
var find = document.getElementById("find").value;
var replace = document.getElementById("replace").value;
var res = str.replaceAll(find, replace);
document.getElementById("message").value = res; //use value here
}
Note: There is no element with id demo in the HTML which is used in your JS.
Demo:
function manage(txt) {
var input = document.getElementById('replace');
if (txt.value != '') {
input.disabled = false;
}
else {
input.disabled = true;
}
}
function findReplace() {
var str = document.getElementById("message").value;
console.log(str)
var find = document.getElementById("find").value;
var replace = document.getElementById("replace").value;
var res = str.replaceAll(find, replace);
document.getElementById("message").value = res;
}
function Counter(str) {
var str = document.getElementById("message").innerHTML;
var msg = str.split(" ");
var element = document.getElementById("replace").value;
var count = 0;
for ( var i = 0; i < msg.length; i++)
{
if (element == msg[i])
{
count++;
i++;
} else
{
i++;
}
//document.getElementById("demo").innerHTML = "Number of replacement: " + count;
}
}
<!-- Message -->
<label for="message">Message: </label><br>
<textarea required type = "text" id="message" name = "message" rows="3" cols="20" method = "post">Hello testing</textarea><br>
<!-- Finding box -->
<label for="find">Find: </label><br>
<input type="text" id="find" name="find" onkeyup = "manage(this)"><br>
<!-- Replace box -->
<label for="replace">Replace with: </label><br>
<input disabled type="text" id="replace" name="replace">
<!--Submit button -->
<input type="button" value="find and replace" onclick ="findReplace(); Counter();">

How to use HTML form input as JS variable

I am trying to make some element change color according to the number received from the form.
e.g. When a player types 2 in the form, there should be 2 colors from the 'color' array.
function intro() {
var num = document.getElementById('quant').value;
var color = ["#FCB711", "#F37021", "#CC004C", "#6460AA", "#0080D0", "#0DB14B"];
var i;
for (i = 1; i <= 42; i++) {
document.getElementById('s' + i).style.backgroundColor = color[getRndInteger(0, num)];
}
}
<form id="tion" action="" method="get">
Player (between 2 and 6):
<input type="number" name="quant" min="2" max="6">
<input type="button" value="start" onclick="intro()">
</form>

Because you're not showing relevant parts of your code, I've simplified it. Your input was missing an id="quant" which I added.
function colorTheDiv() {
const color = ["#FCB711", "#F37021", "#CC004C", "#6460AA", "#0080D0", "#0DB14B"];
document.getElementById('colorMe').style.backgroundColor = color[parseInt(document.getElementById('quant').value)];
}
<label for="quant">Player (between 2 and 6)</label>
<input type="number" name="quant" id="quant" min="2" max="6" onchange="colorTheDiv()">
<hr />
<div id="colorMe">colorMe</div>
I've also replaced the button and execute the colorTheDiv function whenever the value of quant changes (if you prefer you can still keep the button instead).

Start by giving your field an ID of quant.
You are missing 42 elements too
I assume you ACTUALLY meant this
var color = ["#FCB711", "#F37021", "#CC004C", "#6460AA", "#0080D0", "#0DB14B"];
function getRndInteger(max) {
return Math.floor(Math.random() * max);
}
function intro() {
var container = document.getElementById("container");
container.innerHTML = "";
var num = document.getElementById('quant').value;
if (!num) {
alert("Give a value")
return;
}
for (var i = 1; i <= 42; i++) {
var col = color[getRndInteger(num)];
var span = document.createElement("span");
span.innerText = i;
span.id = "s" + i;
span.style.backgroundColor = col;
container.appendChild(span)
}
}
<form id="tion" action="" method="get">
Player (between 2 and 6):
<input type="number" id="quant" min="2" max="6">
<input type="button" value="start" onclick="intro()">
</form>
<div id="container"></div>

you need to give your field an ID of "quant" not just a name, otherwise getElementByID will return null

How to accept the input from a text box and display in array format in jQuery?

I have written the code of taking input value from a text box and adding it to an array using the add button and also displaying the values of the array when the display button is clicked.
The thing is I did all this using JavaScript and now I want to do it using jQuery. I tried a code snippet from this website but it's not working. Please help.
<body>
<script src="jquery-3.3.1.js"></script>
<input type="text" id="text1"></input>
<input type="button" id="button1" value="Add" onclick="add_element_to_array();"></input>
<input type="button" id="button2" value="Display" onclick="display_array();"></input>
<div id="Result"></div>
<script>
var x = 0;
var sample = []; // <-- Define sample variable here
function add_element_to_array(){
$(document).on('click', '#btnSubmit', function () {
var test = $("input[name*='i_name']");
$(test).each(function (i, item) {
sample.push($(item).val());
});
console.log(sample.join(", "));
});
}
function display_array() {
var e = "<hr/>";
for (var y = 0; y < sample.length; y++) {
e += "Element " + y + " = " + sample[y] + "<br/>";
}
document.getElementById("Result").innerHTML = e;
}
</script>
</body>

You can use this code to get idea of how it should work. You can also check for non-empty value before pushing the value into the array as an empty value in array will not make any sense.
$(document).ready(function(){
var valueArray = [];
//add value in array
$('#button1').click(function(){
var textValue = $('#text1').val();
//push non empty value only
if(textValue.trim() !== ''){
valueArray.push(textValue);
//reset the text value
$('#text1').val('');
}
});
//display value
$('#button2').click(function(){
$('#Result').html(valueArray.toString());
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" id="text1"></input>
<input type="button" id="button1" value="Add"></input>
<input type="button" id="button2" value="Display"></input>
<div id="Result"></div>

I have added the jquery script considering the following as your suggested html.
<input type="text" id="text1"></input>
<input type="button" id="button1" value="Add"></input>
<input type="button" id="button2" value="Display"></input>
<div id="Result"></div>
The inptArr must be a global array.
<script>
var inptArr = [];
$('#button1').on('click',function(){
if($('#text1').val() != '')
inptArr.push($('#text1').val());
});
$('#button2').on('click',function(){
var string = '';
var lastIndex = parseInt(inptArr.length - 1);
for(var i = 0; i <= lastIndex ; i++)
{
if(i == lastIndex)
string += inptArr[i];
else
string += inptArr[i] + ',';
}
$('#Result').append(string);
});
</script>

This is another way to achieve what you want with minor changes.
You have only one text input element so don't need any each loop.
document.ready() is needed if you define script from starting of the code because at starting there is no defined element that have an id as btnSubmit so this block must wait to dom elements to be ready.
Also you don't need pure javascript code getElementById on display_array() function when you use jquery. You can change it as $("#Result").html(e);
var x = 0;
var array = [];
$(document).ready(function(){
$('#btnSubmit').on('click', function () {
array.push($("#text1").val());
});
});
function display_array() {
var e = "<hr/>";
for (var y = 0; y < array.length; y++) {
e += "Element " + y + " = " + array[y] + "<br/>";
}
$("#Result").html(e);
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" id="text1"/>
<input type="button" id="btnSubmit" value="Add"/>
<input type="button" id="button2" value="Display" onclick="display_array();"/>
<div id="Result"></div>

In your code functions passed to onclick attributes are binding the click event to a DOM - don't do that.
var array = Array();
var input = $("#text1");
var result = $("#result");
function add_element_to_array(){
var value = input.val();
array.push(value);
console.log("Add:", value);
// input.val(""); // bonus: clears input after adding text to an array
}
function display_array() {
result.text(array.toString());
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="text" id="text1">
<input type="button" id="button1" value="Add" onclick="add_element_to_array();">
<input type="button" id="button2" value="Display" onclick="display_array();">
<div id="result"></div>

How correctly check if input is not equal zero

I have simple code, in input user inputs number and it must print the numbers until the input is not equal to zero.
And the problem is when i submit value, page stops responding
Here is how my code looks like:
window.onload = function() {
var btn = document.getElementsByClassName('btn')[0];
function printInput() {
var output = document.getElementsByClassName('output')[0];
var input = document.getElementsByClassName('input')[0].value;
while(input !== 0) {
var input = document.getElementsByClassName('input')[0].value;
output.innerHTML += input+'<br>';
}
}
btn.addEventListener('click', printInput);
}
<input type="text" class="input" maxlength="1">
<button class="btn">Submit</button>
<div class="output"></div>

The value property of input is a string.
You must compare with the correct type:
while (input !== '0')
or
while (input != 0)
----- edit -----
Consider changing the while to an if, otherwise it will print any number different of 0 indefinitely.
window.onload = function() {
var btn = document.getElementsByClassName('btn')[0];
function printInput() {
var output = document.getElementsByClassName('output')[0];
var input = document.getElementsByClassName('input')[0].value;
if(input !== '0') {
var input = document.getElementsByClassName('input')[0].value;
output.innerHTML += input+'<br>';
}
}
btn.addEventListener('click', printInput);
}
<input type="text" class="input" maxlength="1">
<button class="btn">Submit</button>
<div class="output"></div>

You need to make two changes
Change type attribute from text to number
Change from while to if
Demo
window.onload = function()
{
var btn = document.getElementsByClassName('btn')[0];
function printInput()
{
var output = document.getElementsByClassName('output')[0];
var input = document.getElementsByClassName('input')[0].value;
if (input !== 0)
{
var input = document.getElementsByClassName('input')[0].value;
output.innerHTML += input + '<br>';
}
}
btn.addEventListener('click', printInput);
}
<input type="number" class="input" maxlength="1">
<button class="btn">Submit</button>
<div class="output"></div>

Adding input fields to a HTML form

I want to dynamically add form input fields to a form using the javascript below by clicking on the add button:
var i = 0;
function increment() {
i += 1;
}
function addfieldFunction() {
var r = document.createElement('div');
var y = document.createElement("INPUT");
var z = document.createElement("INPUT");
y.setAttribute("class", "dash-input");
y.setAttribute("type", "text");
y.setAttribute("placeholder", "University");
z.setAttribute("class", "dash-input");
z.setAttribute("type", "text");
z.setAttribute("placeholder", "Course");
increment();
y.setAttribute("Name", "a_level[ + i ][0]");
r.appendChild(y);
z.setAttribute("Name", "a_level[ + i ][1]");
r.appendChild(z);
document.getElementById("form-div").appendChild(r);
}
<form class = "dash-form" method = "POST" action = "/" >
<div id = "form-div">
<input class = "dash-input" type = "text" name = "a_level[+i][0]" value = "" placeholder = "University"/>
<input class = "dash-input" type = "text" name = "a_level[+i][1]" value = "" placeholder = "Course"/>
</div>
<div class = "dash-submit">
<input class = "dash-submit-button" type = "submit" value = "Submit"/>
</div>
</form>
<div class = "dash-add">
<button class = "dash-add-button" onclick = "addfieldFunction()">ADD</button>
</div>
The function returns an i instead of incrementing and returning an integer as shown below:
<div id = "form-div">
<input class = "dash-input" type = "text" name = "a_level[0][0]" value = "" placeholder = "University"/>
<input class = "dash-input" type = "text" name = "a_level[0][1]" value = "" placeholder = "Course"/>
</div>

Concatenate variable i using +(concatenation operator) operator
The concatenation operator (+) concatenates two string values together, returning another string that is the union of the two operand strings.
var i = 0;
function increment() {
i += 1;
}
function addfieldFunction() {
var r = document.createElement('div');
var y = document.createElement("INPUT");
var z = document.createElement("INPUT");
y.setAttribute("class", "dash-input");
y.setAttribute("type", "text");
y.setAttribute("placeholder", "University");
z.setAttribute("class", "dash-input");
z.setAttribute("type", "text");
z.setAttribute("placeholder", "Course");
increment();
y.setAttribute("name", "a_level[ " + i + " ][0]"); //Keep attribute in lower case
r.appendChild(y);
z.setAttribute("name", "a_level[ " + i + "][1]");
r.appendChild(z);
document.getElementById("form-div").appendChild(r);
}
<form class="dash-form" method="POST" action="/">
<div id="form-div">
<input class="dash-input" type="text" name="a_level[+i][0]" value="" placeholder="University" />
<input class="dash-input" type="text" name="a_level[+i][1]" value="" placeholder="Course" />
</div>
<div class="dash-submit">
<input class="dash-submit-button" type="submit" value="Submit" />
</div>
</form>
<div class="dash-add">
<button class="dash-add-button" onclick="addfieldFunction()">ADD</button>
</div>

You need to concatenate it like this:
y.setAttribute("name", "a_level[" + i +"][0]");
As Rayon pointed out: keep attributes in lower case although the HTML5 standard does not require lower case attribute names (see here). W3C recommends it though and XHTML validation would fail using uppercase letters.