I have been trying to change the height of textarea when the user hits enter so they do not have to scroll. i could mange it on IE and Chrome however i could not make it work on Firefox. Please have a look at my code. i am really new to this. it seems like it does not recognize event and i could not figure out a way around.
Here is my code:
<form id="blog-comment-form" method="post" action="index.php">
<textarea id="comment" name="b_com" onkeyup="showmsg()" placeholder="ADD YOUR COMMENT HERE"></textarea>
<input type="submit" name="submit" value="POST COMMENT"/>
</form>
i am calling the function from an external file.
And my javascript code:
function showmsg() {
if(!event){
event= window.event;}
if (event.keyCode==13) {
var a = document.getElementById("comment");
var b = document.getElementById("comment").style.scrollHeight;
a.style.height = ((a.scrollHeight)+6) + "px";
}else {
var a = document.getElementById("comment");
var b = document.getElementById("testthis").style.height;
a.style.height = ((a.scrollHeight)+6) + "px";
}
}
Thank You
Write this:
function showmsg(event) {
in place of:
function showmsg() {
AND
write this (in HTML markup):
onkeyup="showmsg(event)"
in place of:
onkeyup="showmsg()"
You need to add rows attribute to text area. That will help you to increase the height of textarea
Instead of using the onkeyup attribute you can listen to the keyup event in a different way, that will also create the event object for you:
document.getElementById('comment').addEventListener('keyup', showmsg);
A working example:
http://jsfiddle.net/rotev/FKDVD/1/
Tested on Firefox and Chrome.
There a couple of things wrong with your code.
On some browsers your event handling may not work correctly.
So firstly, you need to get the event from callback itself, and not use a global variable called event.
To resize the textarea you can use the properties cols and rows.
To handle the event, you can attach the callback in the following way:
function init(){
var e = document.getElementById("comment");
e.onkeyup = showmsg;
}
For more about event listener, check this out.
To resize the textarea you may use rows:
function showmsg(event) {
if (event.keyCode==13) {
var a = document.getElementById("comment");
a.rows++;
}
}
To call init you may associate it to the element body:
<body onload="init()">
The final code would look like:
<html>
<head>
<script>
function init(){
var e = document.getElementById("comment");
e.onkeyup = showmsg;
}
function showmsg(event) {
if (event.keyCode==13) {
var a = document.getElementById("comment");
a.rows++;
}
}
</script>
</head>
<body onload="init()">
<form id="blog-comment-form" method="post" action="index.php">
<textarea id="comment" name="b_com" placeholder="ADD YOUR COMMENT HERE"></textarea>
<input type="submit" name="submit" value="POST COMMENT"/>
</form>
</body>
</html>
Related
I'm using wordpress but making my own form for payments, i have two inputs of type select, like this:
<div id="S03" class="Selectos"><select tabindex="4" name="Mes" required="">
<option...[Code goes on]
And this:
<div id="S04" class="Selectos"><select tabindex="5" name="Ano" required="">
<option...[Code goes on]
Those works fine, but i want to join them in one input, i have research all day long, i found some clues about what i have to do, but in especifics no one does help me.
This is the input for the joining:
<input id="Expires" name="Expires" type="hidden" />
And the way i call the form:
<div class="container"><form id="contact" class="RV_donateForm" action="https://eps.banorte.com/secure3d/Solucion3DSecure.htm" method="post">
And how it close:
<fieldset><button id="contact-submit" name="submit" type="submit" data-submit=" ">Donar</button></fieldset>
</form></div>
Then i look for some way to joining and this one looks the better way to do it at the submit event:
<script type="text/javascript">
button.onclick = function (){
document.getElementById('Expires').value = document.getElementById('S03').value + '/' + document.getElementById('S04').value; cn = document.getElementById('Expires').value ;
alert(cn);
};
</script>
Well, at the bank 'post' they throw me all the vars ok, except for Expires that never joins and shows null, and i notice also because it never show me the alert. I'm new at html and JavaScript, and i'm not sure what could be wrong. All the code on the file are on this order for exception that the call of the form is at the beginning of everything, ¿maybe is the position on line that i have to put the javascript?
I appreciate any help. Thanks a lot stackfellas!
You may want to check this https://developer.mozilla.org/es/docs/Web/API/EventTarget/addEventListener
I guess you first need to get the button, then add the listener
<script type="text/javascript">
var button = document.getElementById('contact-submit')
button.addEventListener('click', function () {
document.getElementById('Expires').value = document.getElementById('S03').value + '/' + document.getElementById('S04').value;
cn = document.getElementById('Expires').value ;
alert(cn);
});
</script>
Finally! It does work like Omar says, but loading the addEventListener at onload body function, it will run the function that the event refers when you click on submit button.
<script type="text/javascript">
function putExpires(){
var cm = document.getElementById('S03').value;
var ca = document.getElementById('S04').value;
document.getElementById("Expires").value = cm + '/' + ca;
var cn = document.getElementById("Expires").value;
}
function load() {
var button = document.getElementById("contact-submit");
button.addEventListener("click", function(){putExpires()}, false);
}
</script>
<body onload="load();">
Thanks Omar!
Please let me know what I am doing wrong, I have tried to debug but it hasn't been working. I want to enter information into a text field and then display that after clicking a button.
<!DOCTYPE html>
<html>
<head>
<script type = 'text/javascript'>
var name; //name
console.log("hi from script");
function getName() { //get name
return document.getElementById("name").value;
}
function display() { //get the name and display
name = getName();
alert(name);
}
document.getElementById("Submit").onclick = display();
</script>
</head>
<body>
<form id='form'method = 'post'>
<p> Name: <input type="text" id="name"/></p>
<p><input id ="Submit" type = "button" value = 'Submit' /></p>
</form>
</body>
</html>
The problem is that you are making use of a <form> POST. The default behaviour is to navigate away from the page (or refresh if you're posting to the same page), and doing so would mean that the script cannot execute any further functionality. To prevent this, you need to use .preventDefault() to prevent the default behaviour of the form submission.
In order to do this, I've changed your .onclick = display() functionality to add an event listener on the click, which prevents the default behaviour, and then calls display():
.addEventListener("click", function(event) {
event.preventDefault();
display();
});
Adding this provides the following working example:
var name; //name
console.log("hi from script");
function getName() { //get name
return document.getElementById("name").value;
}
function display() { //get the name and display
name = getName();
alert(name);
}
document.getElementById("Submit").addEventListener("click", function(event) {
event.preventDefault();
display();
});
<form id='form' method='post'>
<p> Name: <input type="text" id="name" /></p>
<p><input id="Submit" type="button" value='Submit' /></p>
</form>
Hope this helps! :)
Create an empty p tag and give it an id, then call the id and .html to input the text into the field. Like so
so get your html ready
<p><span id="youridhere"><p>
then add this to your function instead of using alert.
$('#youridhere').html(name);
that should do it
here's a jsfiddle of what I think you are looking for
https://jsfiddle.net/uzdt715L/
$('button').click(function(){
var thing = $('#whatever').val();
$('#final').html(thing);
});
You need to update your click handler syntax. The following should work for you,
document.getElementById("Submit").addEventListener("click", display);
See this related question - addEventListener vs onclick
Your code is not really wrong.
But because the JavaScript is placed before htm code, so the onlick event is not registered.
You must replace
document.getElementById("Submit").onclick = display();
With
document.onload = function() {
document.getElementById("Submit").onclick = display();
}
Sorry for the formatting as I'm answering via mobile.
I am providing a form where the user shall enter an arithmetic calculation. Further down the result shall appear, once the user hits enter. It might just be a problem of syntax, but I couldn't find the mistake. Here is what I did so far:
<!DOCTYPE html>
<html>
<body>
<p>What do you want to calculate?</p>
<form method="post"><span>Type here:</span><input type="text" id="calc"></input>
</form>
<script>
num_field = document.getElementById("calc");
num_field.onsubmit=function ()
{
document.getElementById("display_result").innerHTML = num_field;
}
</script>
<p id="display_result"></p>
</body>
</html>
So, the user shall enter for instance "1+2". The result shall appear below.
Any idea where is my mistake?
Best regards
Here is how you can achieve that.
eval is the best way for doing that but eval is risky to use so make sure to sanitize the value of input before using eval.
I am using this regex /(^[-+/*0-9]+)/g to extract only numbers and few operators (-+/*) and doing eval on that value.
remove the <form> that is not required use keypress event listener and check for enter key. keycode of enter key is 13
num_field = document.getElementById("calc");
num_field.onkeypress = function(e) {
if(e.which==13)
{
var value = num_field.value.match(/(^[-+/*0-9]+)/g);
if(!value) return;
else value = value[0];
var res = eval(value);
document.getElementById("display_result").innerText = res;
}
}
<p>What do you want to calculate?</p>
<span>Type here:</span>
<input type="text" id="calc" />
<p id="display_result"></p>
You were nearly there, your code just needed a bit of tweaking - see below (comments in code as what I have done and why)
The following seems to be an alternate and safer way to do this without using eval (function taken from the second answer in this post):
<!DOCTYPE html>
<html>
<body>
<p>What do you want to calculate?</p>
<form method="post" id="form">
<span>Type here:</span>
<input type="text" id="calc"> <!-- inputs are self closing no need for closing tag -->
<input type="submit" value="submit"> <!-- added a submit button -->
</form>
<script>
form = document.getElementById("form");
num_field = document.getElementById("calc");
form.onsubmit = function() { // attach this event to the form
document.getElementById("display_result").innerHTML = evalAlternate(num_field.value); // add .value here to get the value of the textbox
return false; // return false so form is not actually submitted and you stay on same page (otherwise your display result will not be updated as the page is reloaded
}
function evalAlternate(fn) { // function safer alternate to eval taken from here: https://stackoverflow.com/questions/6479236/calculate-string-value-in-javascript-not-using-eval
fn = fn.replace(/ /g, "");
fn = fn.replace(/(\d+)\^(\d+)/g, "Math.pow($1, $2)");
return new Function('return ' + fn)();
}
</script>
<p id="display_result"></p>
</body>
</html>
see the below fiddle
https://jsfiddle.net/ponmudi/13y9edve/
num_field = document.getElementById("calc");
num_field.onkeydown = (event) => {
if (event.keyCode === 13) {
document.getElementById("display_result").innerHTML = eval(num_field.value);
return false;
}
}
This should work:
calc = document.getElementById("calc");
formula = document.getElementById("formula");
calc.addEventListener('click', function() {
document.getElementById("display_result").innerHTML = eval(formula.value);
});
<p>What do you want to calculate?</p>
<span>Type here:</span>
<input type="text" id="formula" />
<button id="calc" type="submit">calc</button>
<p id="display_result"></p>
eval() JavaScript Method
Try this:
var calculation_input = document.getElementById('calculation_input');
calculation_input.onkeydown = function(event) {
if (event.keyCode == 13) { // Enter key.
// Sanitize before using eval()
var calculation = calculation_input.value.replace(/[^-()\d/*+.]/g, '');
document.getElementById("display_result").innerHTML = eval(calculation);
}
}
<p>What do you want to calculate?</p>
<span>Type here:</span>
<input type="text" id="calculation_input" />
<p id="display_result"></p>
You don't need to submit the calculation in a form, you can just use native javascript to calculate the result. And don't forget to always sanitize before using eval :)
I'm trying to simply have a button update the contents of ah HTML textbox (on the client side).
Clicking the button fires the updateBox() method fine. Stepping through the code, I can see the text1.value field update fine but the text1 does not seem to get updated by changes to the dom.
Am I mistaken to think that you can do updates on the client side only by modifying dom data?
<input type=text name="text1" value="100"/>
<button name="but1" id="but1" onclick="updateBox" >clickme!</button>
<script type="text/javascript" >
var text1 = document.getElementsByName('text1');
function updateBox() {
//text1.value = "22"; <----tried this way, no good either :(
text1.innerHTML = "99";
}
</script>
Few things:
onclick="updateBox" should be onclick="updateBox()"
var text1 = document.getElementsByName('text1'); should be var text1 = document.getElementsByName('text1')[0]; (note the [0])
text1.value = "22"; is the one to use
jsFiddle example
Try use below,
var text1 = document.getElementsByName('text1')[0];
function updateBox() {
text1.value= "99";
}
Ref: https://developer.mozilla.org/en-US/docs/Web/API/document.getElementsByName
Thanks for everyone's responses.
With your advice I got the button to update. I appreciate the advice on how to implement the function correctly. This was just a test so I didn't pay much attention.
1) I had to use: onclick="updateBox" rather than "updateBox() in the button HTML because "updateBox" caused the event to fire with out clicking the button.
2) Big thanks for pointing out that I was referencing a collection instead of an item in the collection. Had to use: var tb1 = document.getElementsByName('tb1')[0];
3) For some reason the box would not update when I used:tb1.innerHTML = "99";
This worked: tb1.value = "99";
text1[0].innerHTML = "99"
Use innerHTML instead of value
try passing the variable to your function instead of declaring it outside of your function.
<input type=text name="text1" value="100"/>
<button name="but1" id="but1" onclick="updateBox('text1',99)" >clickme!</button>
<script type="text/javascript" >
function updateBox(t,v) {
var tv = document.getElementsByName(t)[0];
tv.value = v;
}
</script>
Please could you advise on the following:
I have a registration form, and within that a text area
<form id="register" name="register" method="post" action="register.php">
<textarea rows="5" id="bio" name="bio" method="post">Biographical information</textarea>
</form>
Using java script i have been trying to create an event handler for the onfocus and onblur events so the default text is removed on focus and restored on blur, as follows:
var bioField = document.getElementById("bio");
bioField.onfocus = function() {
if (bioField.value == "Biographical information") {
bioField.value = "";
}
};
bioField.onblur = function() {
if (bioField.value == "") {
bioField.value = "Biographical information";
}
};
i thought by getting the element by id would work, but it doesn't seem to be. no other duplication of names/id exist.
Any help much appreciated.
Thanks guys
Use the placeholder attribute:
<textarea rows="5" id="bio" name="bio" method="post" placeholder="Biographical information"></textarea>
It's working fine, perhaps the issue is that the placeholder default is "Biographical Information" and the script is testing for "All about you". The change that you made as I was posting this is exactly what you needed.
var bioField = document.getElementById("bio");
bioField.onfocus = function() {
if (bioField.value == "Biographical information") {
bioField.value = "";
}
};
bioField.onblur = function() {
if (bioField.value == "") {
bioField.value = "Biographical information";
}
};
http://jsfiddle.net/YeaTQ/1/
My educated guess is that you've placed your code as is right into a <script> tag inside <head> so when the script runs the form has not loaded yet.
Move your <script> below the form or wrap everything with window.onload:
window.onload = function(){
// Code goes here
};
You have two solutions:
In order to not use the javascript code you wrote, Use the following code:
<textarea cols="30" rows="5" id="bio" name="bio" onfocus="this.value = '' " onblur="this.value = 'All about you'">Biographical information</textarea>
I think the javascript code is located before control (in the header I guess), Because of this, the onfocus and onblur properties are not initialized. You'll have to put the script at the end of the document (before the tag).
Also, you script is searching for another text ("All about you") and not the current text that's inside ("Biographical information"). Even if you insert the javascript code at the of the document, the code it will work.