Develop Reference

HTML selectpicker multiple , options "all" disable all other options

I have a select picker element like this in my web page :
<select id="difficulty" name="difficulty" class="selectpicker" multiple onchange="ChangeFilters()">
<option value="-1" selected >All</option>
<option value="0" >Facile</option>
<option value="1" >Normal</option>
<option value="2" >Difficile</option>
</select>
I want that when the user select the "All" options (value = '-1') , if there are other options selected they become not selected, and if the option all is selected when the user select an other options the "all option" become not selected.
I have searched for like 2 hours and i can't make this working.
I work with bootstrap and this select element is a selectpicker element, my javascript don't work when i try something ..
Please help !
EDIT :
I posted the working code as an answer, thanks for your help !

Something like this?
function ChangeFilters(){
var selVal = $('#difficulty').val()[0];
if(selVal == -1){
$('#difficulty').attr('multiple',false);
}else{
$('#difficulty').attr('multiple',true);
}
}

With the help of this post Select all / Unselect all in Bootstrap Select plugin
This is the full working code which allow the user to select the All option, 3 difficulties, or nothing :
HTML :
<select id="difficulty" name="difficulty" class="selectpicker" multiple onchange="ChangeFilters()">
<option value="All" selected >Tous</option>
<option value="0" >Facile</option>
<option value="1" >Normal</option>
<option value="2" >Difficile</option>
</select>
Javascript :
//This need to be on your page load or other load event before the first onChange.
$('#difficulty').data('allOptionIsSelected', true);
function ChangeFilters() {
if ($('#difficulty') != null) {
if ($('#difficulty').val() != null) {
var allOptionIsSelected = ($('#difficulty').val() || []).indexOf("All") > -1;
function valuesOf(elements) {
return $.map(elements, function (element) {
return element.value;
});
}
if ($('#difficulty').data('allOptionIsSelected') != allOptionIsSelected) {
//User clicked 'All' option
if (allOptionIsSelected) {
$('#difficulty').selectpicker('val', ["All"]);
$('#difficulty').selectpicker('refresh');
} else {
}
} else {
// User clicked other option
if ($('#difficulty').val().length != $('#difficulty').find('option').length) {
//user clicked other
// All options were selected, user deselected one option
// => unselect 'All' option
$('#difficulty').selectpicker('val', valuesOf($('#difficulty').find('option:selected[value!=All]')));
allOptionIsSelected = false;
}
}
$('#difficulty').data('allOptionIsSelected', allOptionIsSelected);
}
$('#difficulty').selectpicker('refresh');
}
}
If you want to make this work with your project, change '#difficulty' to the id of your select control.
Thanks to #yuriy636 for the previous help :)

how to dynamically add REQUIRED attribute to input tags based on output of select tag using jquery?

I have a select tag with two options 'new' and 'edit'
when someone selects the 'new' option all the input tags in that form should be marked required and when someone selects 'edit' only a few should be marked required.
<select name="todo" id="todo" required>
<option value="">---</option>
<option value="new">Add</option>
<option value="edit">Edit</option>
</select>
Now I tried some functions but they don't seem to work
<script>
var todo = $('#todo option:selected').text();
if (todo == "new") {
$('#Name').attr('required',true);
} else if (todo == "edit") {
//code
}
</script>
and
<script>
function req() {
var selectBox = document.getElementById('todo');
var userInput = selectBox.options[selectBox.selectedIndex].value;
if (userInput == 'new') {
$('#Name').attr('required',true);
} else if (todo == "edit") {
//code
}
}
</script>
where
<select name="todo" id="todo" onchange="return req();" required></select>
just to be sure if it works I put a alert() method in the if condition, but that alert is never fired.
PS. one of the input tags is
<input type="text" id="Name" name="Name">
Thank you for your time in advance...
EDIT
As pointed out by #Maximillian Laumeister in second snippet there was a typo error (which I have corrected here). (sorry for that)

This should be ebough to get you going.
onchange detects whenever a different selection is made. Then based on what option is selected you perform the different instructions.
jQuery(document).ready(function(){
jQuery('#todo').on('change', function(event){
alert(this.value);
if(this.value === 'edit'){
}
else if(this.value === 'new'){
}
})
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.0/jquery.min.js"></script>
<select name="todo" id="todo" required>
<option value="">---</option>
<option value="new">Add</option>
<option value="edit">Edit</option>
</select>

In your script here you have a typo that throws a console error:
function req() {
var selectBox = document.getElementById('todo');
var userInput = selectBox.options[selectbox.selectedIndex].value;
if (userInput == 'new') {
$('#Name').attr('required',true);
} else if (todo == "edit") {
//code
}
}
Where it says
selectBox.options[selectbox.selectedIndex].value
selectBox needs a capitalization like this:
selectBox.options[selectBox.selectedIndex].value
It seems to be working for me with that one change.
Also, since you asked, your first script isn't working because it needs to be bound to run when the select changes, just like with the first one. In addition, you need to use jQuery's val instead of text to get the value of an option tag. Here is a working version of your second script:
$("#todo").change(function () {
var todo = $('#todo option:selected').val();
if (todo == "new") {
$('#Name').attr('required',true);
} else if (todo == "edit") {
//code
}
});

Try this:
$("select").change(function(){
if($(this).val() === "new")
$("#Name").attr("required","required");
});
You used the option text which is "Add" but in your if statement you compared it to the string "new". That's the reason your code didnt work as expected.

selecting incorrect value HTML <select>

I have HTML:
<select class="form" id="select" name="select">
<option>number1</option>
<option>number2</option>
</select>
<select name="organisation" class="form" id="cent" required>
<option value="1">UK</option>
<option value="2">SPAIN</option>
</select>
And another <select>:
<select class="form" id="ssip" name="organisation">
<option value="47" >US</option>
<option value="48">UKRAINE</option>
</select>
JQuery to show on 1 - first select on 2 - second
$(document).ready(function() {
$("#select").each(function () {
if (this.value == "1") {
$('#cent').show();
$('#ssip').hide();
}
if (this.value == "2") {
$('#cent').hide();
$('#ssip').show();
}
});
});
The problem is that when i choose option number1 appears first select with values 1 and 2 but when i select UK with value 1 and click submit it's sending value 47 , of second select's first option..

Try disabling the opposite select when toggling the selects. A control on a form will still be submitted if its display is set to none, however if the control is disabled it will not be submitted with the form.
$(document).ready(function() {
$("select").change(function () {
if (this.value == "number1") {
$('#cent').show().prop("disabled", false);
$('#ssip').hide().prop("disabled", true);
}
if (this.value == "number2") {
$('#cent').hide().prop("disabled", true);
$('#ssip').show().prop("disabled", false);
}
});
});
JS Fiddle: http://jsfiddle.net/bTJsH/

You are trying to loop one select box..
$("#select").each(function () {
There can be only one element with id "select". You should check like:
if ($("#select").value() == "1") { ..
And you don't even have values in your first select options..

i might suggest something like this
$('#select').on('change', function() {
var selected = this.selectedIndex;
$('.orgs').hide();
switch(selected) {
case 1:
$('#ssip').show();
break;
case 2:
$('#cent').show();
break;
}
});
here is an working example http://jsfiddle.net/pixelchemist/7ZGwy/

How to get checkbox value in multiselect onchange event

I implement jquery multiselect and its working properly now i need to add extra feature that when a user select another option in dropdown ( check another checkbox ) then i want to get the value of the related option
in above picture in did not insert checkbox it is automatically inserted by jquery now i want that if i select the check =box with XYZ then i want to get the value of XYZ which is the id of XYZ
here is how i implemented it
<select multiple="multiple" id="CParent" name="parent" class="box2 required">
#foreach (var item in Model.Categories.OrderBy(c => c.Name))
{
if (Model.Coupon.Categoryid.Id == item.Id)
{
<option selected="selected" value="#item.Id">#item.Name</option>
}
else
{
<option value="#item.Id">#item.Name</option>
}
}
</select>
and it is how it looks like after rendering in browser source
Thanks in advance for helping me .
what i tried yet
$('#CParent input:checked').change(function () {
var parentid = $(this).val()+'';
var array = parentid.split(",");
alert(array);
getchildcat(array[array.length -1]);
});
});
Edit
Code to initialize multiselect
$("#CParent").multiselect({
header: "Choose only THREE items!",
click: function () {
if ($(this).multiselect("widget").find("input:checked").length > 3) {
$(warning).show();
warning.addClass("error").removeClass("success").html("You can only check three checkboxes!");
return false;
}
else if ($(this).multiselect("widget").find("input:checked").length <= 3) {
if ($(warning).is(":visible")) {
$(warning).hide();
}
}
}
});

try this
$('#CParent').val();
this will give you the selectbox value
OR
from docs
var array_of_checked_values = $("#CParent").multiselect("getChecked").map(function(){
return this.value;
}).get();

Using Javascript to hide textfields

If a user selects a certain option value in one select field, how do you then make a text field hidden, s it will not be needed. This must be done before the form is submitted?
For example in the following select field, a user select chooses value='a' then how would this text field become hidden:
<select name="form" id="aForm">
<option value="a">choice1</option>
<option value="b">choice2</option>
<option value="c">choice3</option>
</select>
<input type="text" style="width:285px" name="textField" id="textField"/>

$("#aForm").on("change", function() {
if ($(this).val() == "a")
$("#textField").hide();
else
$("#textField").show();
});
Here is also a jsfiddle
I assumed that you will show the textfield for any other value than a.
If you're using plain JavaScript and not jQuery
function hideTF() {
var s = document.getElementById("aForm");
document.getElementById("textField").style.display
= (s.selectedIndex > 0 && s.options[s.selectedIndex] == 'a'
? "none" : "block");
}
var s = document.getElementById("aForm");
if (s.attachEvent)
s.attachEvent("onchange", hideTF);
else
s.addEventListener("change", hideTF, false);

You can use a variation of this:
var selection = aForm.selectedIndex,
field = document.getElementById('textField');
if ( selection === x ) {
field.style.display = "block"; // or visibility = "hidden"
}
This should be enclosed in an .onchange event. aForm.selectedIndex is the index of the corresponding <option> element that is selected.