How I can make the selected choice still visible until I re-choose another one?The list may contain more than 10 options
=====
<form method="get" action="Chairman.php" >
<select name="courses" id="courses" class="styled-select" >
<option value="courses"><--Courses--></option>
<option value="PHYS220">Physics for Engineers</option>
<option value="MATH210">Calculus II</option>
<option value="MATH225">Linear Algebra with Applications</option>
</select>
<input type="submit" value="Search Instructor"
onClick="checkDropdown()"></input>
<div id="error" style="color:red"></div>
=====
Also when I am trying to validate the select list,The error is displayed and then quickly it disappears
<script>
function checkDropdown () {
var courses = document.getElementById('courses');
if(courses.value==="courses") {
document.getElementById('error').innerHTML="PLEASE selecttt";
return false;
}
}
</script>
The select is reset and the error disappears because the form is still posted. The value that you return from the function doesn't stop the submission.
You should use the onsubmit event on the form instead of onclick on the button. Use return in the event code to convey the value from the function back to the event:
<form method="get" action="Chairman.php" onsubmit="return checkDropdown()">
Related
I'm new to Javascript and HTML.
I have the following form in HTML:
<div id="form-select">
<form id="date_form" action="" METHOD="POST">
<datalist id="dates">
<option value="February 7">February 7</option>
<option value="February 14">February 14</option>
<option value="February 21">February 21</option>
<option value="February 28">February 28</option>
</datalist>
<input type="text" class="input" name="data" id="date" value="" list="dates" placeholder="pick a date"><br>
<input type="submit" name="submit" onClick="myFunction()"/>
</form>
</div>
Here's the javascript in a file called script.js. The js file is linked in the header as 'script type="text/javascript" src="script.js':
function myFunction(){
var input = document.getElementById("date").value;
if(input==="February 7"){
document.getElementById('w1').innerHTML = "<h2> HEADING </h2>;
}
};
When I fill out the form and hit submit, the javascript correctly executes the function, but the result (i.e. adding HEADING to the html) happens for a couple of milliseconds before disappearing and resetting to the original page before I had hit submit.
How do I make it so that the insertion of HEADING remains permanent?
Move the listener to the form's submit handler. Have the function return false to stop submission:
<form id="date_form" onsubmit="return myFunction();" ...>
Take the listener off the button:
<input type="submit">
Do not give it a name of submit as that will mask the form's submit method so you can't call it. Submit buttons only need a name if there are two or more on a form and you want to know which one was used to submit the form.
There is an error in your code, it's missing a closing double qoute:
function myFunction(){
var input = document.getElementById("date").value;
if(input==="February 7"){
document.getElementById('w1').innerHTML = "<h2> HEADING </h2>";
}
return false; // to stop submission
};
This may or may not fix you issues, you haven't said what you are actually trying to do.
I want the to get the required in the html page if none is selected.
function validation() {
var country = getElementById("country");
if (country.value = "") {
documnet.getElementById("countryy").innerHTML = "Required";
return false;
} else
return true;
}
<form onsubmit="return validation();">
<select id="country"><span id="countryy"></span>
</select><br>
<input type="submit" name="Submit" value="Submit">
</form>
Why The Validation is not working for the provided html/ js code. I want the to get the required in the html page if none is selected. I am new to js learning.
Several issues
Spelling mistake in the document.getElementById
missing document on the other document.getElementById
No preventDefault which will submit the form if any JS errors
= is assignment - you need == or === to compare
span needs to be outside the select
You did not use value="Default" in the "NONE" options
It is not recommended to have inline event handlers. Here is a better version
Note I added a class to toggle the required in case the user changes the select to conform
window.addEventListener("load", function() {
const errorSpan = document.getElementById("countryy"); // cache the elements
const country = document.getElementById("country");
document.getElementById("myForm").addEventListener("submit", function(e) {
const val = country.value; // get the value
if (val === "") {
e.preventDefault(); // stop submit
}
errorSpan.classList.toggle("hide",val); // hide if value
})
country.addEventListener("change",function() { // if user changes the select
errorSpan.classList.toggle("hide",this.val); // hide if value
})
})
.hide { display : none; }
<form id="myForm">
<select id="country">
<option value="">NONE</option>
<option value="ABDUL">ABDUL</option>
<option value="SULE">SULE</option>
</select> <span id="countryy" class="hide">Required</span><br>
<input type="submit" name="Submit" value="Submit">
</form>
HOWEVER you could remove all the script and just add required attribute to the select and keep the empty default
<form id="myForm">
<select id="country" required>
<option value="">NONE</option>
<option value="ABDUL">ABDUL</option>
<option value="SULE">SULE</option>
</select><span id="countryy"></span><br>
<input type="submit" name="Submit" value="Submit">
</form>
Use required attribute in the select tag. It will considered in html 5 validation.
https://www.w3schools.com/tags/tryit.asp?filename=tryhtml5_select_required
I have a dropdown that is disabled to the user. I want for the user to be able to press a button that changes the selected item to a different one. For example: from the 4th item in the dropdown to the 7th.
I've tried disabling the dropdown, but when I do that and submit the form, I get a PHP error saying Undefined index: id.
HTML:
<form>
<select id='id' name='id' autocomplete='none' disabled required>
<option value='2'>apple</option>
<option value='6'>banana</option>
<option value='10'>orange</option>
</select>
<button type='submit'>Submit</button>
</form>
JavaScript:
const dropdown = document.getElementById('dropdown');
const options = dropdown.options;
for (let i = 0; i < options.length; ++i) {
if (options[i].value === id) {
dropdown.selectedIndex = i;
break;
}
}
PHP (This line seems to be the one breaking):
$id = $_POST['id'];
It seems you haven't defined method and action in your form tag. By default, I think, the method is set to 'GET', so when checking 'POST' you'll run into your error.
Therefore, set "method='post'" (and best also an action, e.g. "action='/yourPageName.php') and see if that helps.
I figured out a solution that suits my needs. It was kind of simple. I just enabled the dropdown when I submitted the form, and instantly disabled it again.
id.removeAttribute('disabled');
const data = new FormData(document.getElementById('form'));
id.setAttribute('disabled', '');
request.send(data);
Thanks for the help though :)
A disabled input field will be ignored when you submit the form. I would suggest creating a hidden input field of name="id" if you want the user to view the dropdown but not select it.
<form>
<select id='id' autocomplete='none' disabled required>
<option value='2'>apple</option>
<option value='6'>banana</option>
<option value='10'>orange</option>
</select>
<input type="hidden" name='id' value="6" />
<button type='submit'>Submit</button>
</form>
You can make an hidden input with the id="id" and change the select id to "temp_id". Then, since you are making the request from javascript, you can just update the hidden field before making the request.
<select id='temp_id' autocomplete='none' disabled required>
<option value='2'>apple</option>
<option value='6'>banana</option>
<option value='10>orange</option>
</select>
<input type="hidden" name="id" id="id" value="">
Then, on your javascript, just before you make the request, run the code:
document.getElementById("id").value = document.getElementById("temp_id").value;
I have the following code that checks to see that two select fields are identical. The code works alright when called with onsubmit. However after doing this validation the form is still submitted. How can i prevent the script or my form from submitting the incorrect data.
Please see code below:
var fieldalias="Email address field"
function verify(element1, element2) {
var passed=false
if (element1.value=='') {
alert("Please fill out the "+fieldalias+"!")
element1.focus()
}
else if (element2.value=='') {
alert("Please verify the "+fieldalias+"!")
element2.focus()
}
else if (element1.value!=element2.value) {
alert("The two "+fieldalias+"s do not match")
element1.select()
}
else
passed=true
return passed
}
You didn't include your HTML, so I'm going to assume you've added onsubmit() to your form element.
If so, make sure your call looks like this:
onsubmit="return verify(element1, element2)"
(replace element1 and element2 accordingly)
If this assumption is not correct, please include some additional detail so we can better assist.
Try calling stopImmediatePropagation() on the event to prevent any further processing of the submit event by any other handlers in the form element or higher level elements.
Call that code with different event, like i.e: onchange, or onfocusout. This way the validation will be performed every time user enter some values to your fields, certainly before submitting.
EDIT:
I'm not sure if I understand you correctly but I would have attached your JS code this way:
First assign your select box to the variable:
var object_input = document.getElementById("selectId");
And then:
if(object_input.addEventListener)
{
object_input.addEventListener('blur', focus_lost);
object_input.addEventListener('keypress', checkForEnter);
}
else
{
object_input.attachEvent('onblur', focus_lost);
object_input.attachEvent('onkeypress', checkForEnter);
}
and then perform your validation ith focus_lost or checkForEnter.
Assuming that in the html code you have something like this:
<form action="test2.html" method="post" onsubmit="return verify(e1, e2);">
<input type="text" name="e1" /><br/>
<input type="text" name="e2" /><br/>
<input type="submit" value="Validate" />
</form>
You have to put in onsubmit event:
return verify(e1, e2);
so you will not go to the submiting page if the data is not valida
EDIT:
I think the problem is the
element1.select()
in the 3rd if, that this select method does not exist for a select object.
You can use a
element1.focus()
The code that will work is:
var fieldalias="Email address field"
function verify(element1, element2){
var passed=false;
if (element1.value==''){
alert("Please fill out the "+fieldalias+"!");
element1.focus();
}
else if (element2.value==''){
alert("Please verify the "+fieldalias+"!");
element2.focus();
}
else if (element1.value!=element2.value){
alert("The two "+fieldalias+"s do not match");
element1.focus();
}
else
passed=true;
return passed;
}
And
<form action="test2.html" method="post" onsubmit="return verify(document.getElementById('e1'), document.getElementById('e2'));">
<select id="e1">
<option value="One">One</option>
<option value="two">two</option>
<option value="Three">Three</option>
<option value="four">four</option>
</select><br/>
<select id="e2">
<option value="One">One</option>
<option value="two">two</option>
<option value="Three">Three</option>
<option value="four">four</option>
</select><br/>
<input type="submit" value="Validate" />
</form>
I have a small form.
Two select box elements and a submit button.
The select box elements collectively when selections are chosen, fire off an ajax request.
What I want to do is, disable the submit button UNTIL user has made selections from the select drop downs.
They must make a selection from BOTH select drop downs, before the Submit button is enabled.
I dont mind if the submit button is hidden until selections made.
Brief Code:
<form id="ad_form" method="post" action="">
<p>
<select id="ad_type" name="ad_type">
<option value="" selected="selected">Select premium ad type</option>
<option value="<?php echo TYPE_USER;?>">Featured Agent</option>
<option value="<?php echo TYPE_LISTING;?>">Featured Listing</option>
</select>
<label for="ad_type" class="labelStrong">Advertising Type</label>
</p>
<p>
<select id="ad_duration" name="ad_duration">
<option value="" selected="selected">Select premium ad duration</option>
<option value="weekly">Weekly</option>
<option value="fortnightly">Fortnightly</option>
<option value="monthly">Monthy</option>
</select>
<label for="ad_duration" class="labelStrong">Advertising Duration</label>
</p>
<p>
<div id="calender">
</div>
</p>
<p>
<input type="submit" name="submit" value="Submit" id="submitorder" />
</p>
</form>
Here's a demo that seems to do what you want:
http://jsfiddle.net/Yr59d/
That javascript code would go in a $(document).ready() block
$(function() {
$("#submitorder").css("visibility", "hidden");
$("#ad_form select").bind("change", function() {
if ($("#ad_type").val().length > 0 && $("#ad_duration").val().length > 0) {
$("#submitorder").css("visibility", "visible");
} else {
$("#submitorder").css("visibility", "hidden");
}
});
});
If you give all your selects a common class name (like 'required') , you can do something like this:
$('select.required').change(function() {
var total = $('select.required').length;
var selected = $('select.required option:selected').length;
$('#submitorder').attr('disabled', (selected == total));
});
This is not tested code. This documentation might help. This jquery discussion might help too.
Gah, I'll have to agree with Kon on this one - fix-now-worry-about-it-later answers have their place but an elegant solution that is simple at the same time has to be the way to go.
My solution: (with credit from a thread at: JQuery Enable / Disable Submit Button in IE7)
$('select.required').change(function() {
var total = = $('select.required').length;
var selected = $('#ad_form').find("select.required option[value!='':selected").length;
$('#submitorder').prop('disabled', (selected != total));
});
Incidentally, thanks ctcherry for demoing the code on the JSFiddle site - I've not seen that before and will make use of it in the future!
Use listeners on both select buttons for change and check whether the other is also set. If set, enable the submit button.