Develop Reference

How to make multi level dropdown menu using select option mentod

i want to make multi level dropdown menu using select and option method
<select>
<option value="" data-display-text="Select">None</option>
<option value="oranges">SSC</option>
<option value="oranges">GATE</option>
<option value="bananas">BANK PO</option>
<option value="bananas">RAILWAY</option>
</select>

As far as I understand from your "multi level dropdown" concept, you can make a simple dropdown and just move some elements with CSS. Category name is stored in optgroup.
<select name="select_projects" id="select_projects">
<option value="">project.xml</option>
<optgroup label="client1">
<option value="">project2.xml</option>
</optgroup>
<optgroup label="client2">
<option value="">project5.xml</option>
<option value="">project6.xml</option>
<optgroup label="client2_a">
<option value="" style="margin-left:23px;">project7.xml</option>
<option value="" style="margin-left:23px;">project8.xml</option>
</optgroup>
<option value="">project3.xml</option>
<option value="">project4.xml</option>
</optgroup>
<option value="">project0.xml</option>
<option value="">project1.xml</option>
</select>
Update:
Or if you are trying to make a "chain" of dropdowns like you have in start menu in Windows, that is the easiest way to do it:
https://jqueryui.com/menu/

You can't make multiple levels with the select element.
In this case you would create a custom component with the capability to display something like 'hierarchic'.
Or use the trick like this:
<select>
<option>select me</option>
<option> me indented</option>
<option> even more indentation</option>
</select>

If you want to use ONE select you could use <optgroup/>. See example.
Note: it's not very multi-level, but it allows for some kind of relevant grouping.
<select>
<option value="" selected="selected">Select an option...</option>
<optgroup label="SSC">
<option value="oranges1">some option</option>
<option value="oranges2">some option</option>
<option value="oranges3">some option</option>
</optgroup>
<optgroup label="GATE">
<option value="bananas1">some option</option>
<option value="bananas2">some option</option>
<option value="bananas3">some option</option>
</optgroup>
<optgroup label="BANK PO">
<option value="apples1">some option</option>
<option value="apples2">some option</option>
<option value="apples3">some option</option>
</optgroup>
<optgroup label="RAILWAY">
<option value="grapes1">some option</option>
<option value="grapes2">some option</option>
<option value="grapes3">some option</option>
</optgroup>
</select>

You can't make multiple levels with the select element.
Any ways, if its any help, there's
<select>
<optgroup label="Swedish Cars">
<option value="volvo">Volvo</option>
<option value="saab">Saab</option>
</optgroup>
<optgroup label="German Cars">
<option value="mercedes">Mercedes</option>
<option value="audi">Audi</option>
</optgroup>
</select>

Maybe this can insprire you even if not totally correctly interpreted by editors.
<div class="col-2 search-filter">
<select id="searchByYear" multiple="multiple" ng-model="varYear.value">
<option value="2023">2023
<option value="2023-H1">H1</option>
<option value="2023-H2">H2</option>
</option>
<option value="2022">2022
<option value="2022-H1">H1</option>
<option value="2022-H2">H2</option>
</option>
<option value="2021">2021
<option value="2021-H1">H1</option>
<option value="2021-H2">H2</option>
</option>
<option value="2020">2020
<option value="2020-H1">H1</option>
<option value="2020-H2">H2</option>
</option>
<option value="2019">2019
<option value="2019-H1" >H1</option>
<option value="2019-H2" >H2</option>
</option>
</select>
</div>

How to delete the selected option using title attribute of select tag

I want to delete the first option of the selected and I have selected tag id and class but the problem is selected class and id is changing when I open the form of different-2 event.and class "r" of selected tag is using more than one time different-3 drop down of form.
I want to remove the selected option using title attribute of selected tag.
If any other way to resolved this type of problem please share.
<select name="DROPDOWN_735" class="r" id="DROPDOWN_735" title="State*">
<option value="">Select One </option>
<option value="Michigan"> Michigan</option>
<option value="Alabama"> Alabama</option>
<option value="Alaska"> Alaska</option>
<option value="Arizona"> Arizona</option>
<option value="Arkansas"> Arkansas</option>
<option value="California"> California</option>
<option value="Colorado"> Colorado</option>
<option value="Connecticut"> Connecticut</option>
<option value="Delaware"> Delaware</option>
<option value="Florida"> Florida</option>
<option value="Georgia"> Georgia</option>
</select>
I want to delete
<option value="">Select One </option>

Here is how to select using class and title in plain JavaScript
window.onload=function() {
var sel = document.querySelector("select.r[title='State*']");
console.log(sel);
sel.options[0]=null;
}
<select name="DROPDOWN_735" class="r" id="DROPDOWN_735" title="State*">
<option>Please select State</option>
<option>option 1</option>
</select>
<select name="DROPDOWN_735" class="r" id="DROPDOWN_735" title="NotState*">
<option>Please select Not State</option>
<option>option 1</option>
</select>
Ditto in jQuery
$(function() {
var $options = $("select.r[title='State*'] option");
$options.eq(0).remove();
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<select name="DROPDOWN_735" class="r" id="DROPDOWN_735" title="State*">
<option>Please select State</option>
<option>option 1</option>
</select>
<select name="DROPDOWN_735" class="r" id="DROPDOWN_735" title="NotState*">
<option>Please select Not State</option>
<option>option 1</option>
</select>

you can add the hidden attribute:
<option value="" hidden>Select One</option>
this will result in being the default selected value but you can't select it in the dropdown
Example:
<select name="DROPDOWN_735" class="r" id="DROPDOWN_735" title="State*">
<option value="" hidden>Select One</option>
<option value="Michigan">Michigan</option>
<option value="Alabama">Alabama</option>
<option value="Alaska">Alaska</option>
<option value="Arizona">Arizona</option>
<option value="Arkansas">Arkansas</option>
<option value="California">California</option>
<option value="Colorado">Colorado</option>
<option value="Connecticut">Connecticut</option>
<option value="Delaware">Delaware</option>
<option value="Florida">Florida</option>
<option value="Georgia">Georgia</option>
</select>
The hidden attribute can also be used to keep a user from seeing an element until some other condition has been met (like selecting a checkbox, etc.).
The hidden attribute is new in HTML5.
Source: http://www.w3schools.com/tags/att_global_hidden.asp

In your scenario if select box's id is changing dynamically then you can achieve this with it's class name like below
$(".r option[value='']").each(function() {
$(this).remove();
});
If you want to delete it by using ID then you can do it like this..
$("#DROPDOWN_735 option[value='']").each(function() {
$(this).remove();
});
Or
$("select option[value='']").each(function() {
$(this).remove();
});

Try this
$(document).ready(function() {
$("select[title='State*'] option:first-child[value='']").remove();
})
<script src="https://ajax.aspnetcdn.com/ajax/jQuery/jquery-3.1.1.min.js"></script>
<select name="DROPDOWN_735" class="r" id="DROPDOWN_735" title="State*">
<option value="">Select One </option>
<option value="Michigan"> Michigan</option>
<option value="Alabama"> Alabama</option>
<option value="Alaska"> Alaska</option>
<option value="Arizona"> Arizona</option>
<option value="Arkansas"> Arkansas</option>
<option value="California"> California</option>
<option value="Colorado"> Colorado</option>
<option value="Connecticut"> Connecticut</option>
<option value="Delaware"> Delaware</option>
<option value="Florida"> Florida</option>
<option value="Georgia"> Georgia</option>
</select>
<select name="DROPDOWN_735" class="r" id="DROPDOWN_735" title="State*">
<option value="">Select One </option>
<option value="Michigan"> Michigan</option>
<option value="Alabama"> Alabama</option>
<option value="Alaska"> Alaska</option>
<option value="Arizona"> Arizona</option>
<option value="Arkansas"> Arkansas</option>
<option value="California"> California</option>
<option value="Colorado"> Colorado</option>
<option value="Connecticut"> Connecticut</option>
<option value="Delaware"> Delaware</option>
<option value="Florida"> Florida</option>
<option value="Georgia"> Georgia</option>
</select>
Hope it will be useful.

Connected select tags

I'm have several select tags on one page, grouped 3 by 3.
And I want every group by 3 to share the same option list, where if the user chooses "Sweden" in the first box, then "Sweden" is removed from the options of the second box. But here is the tricky part, IF the user decides to change the first box again to lets say "England", then "Sweden" will be back in the list of the second select box. Sounds fuzzy?
My code manages to remove a country from the next box but then it is removed for good, also the change is only affecting the closest Select tag right now. I would like to change the content for all 4 select tags in that group.
Here is my code, please point me in the right direction:
<div id="group1">
<div>
<select>
<option value="France">France</option>
<option value="Sweden">Sweden</option>
<option value="England">England</option>
<option value="Germany">Germany</option>
<option value="USA">USA</option>
</select>
</div>
<div>
<select>
<option value="France">France</option>
<option value="Sweden">Sweden</option>
<option value="England">England</option>
<option value="Germany">Germany</option>
<option value="USA">USA</option>
</select>
</div>
<div>
<select>
<option value="France">France</option>
<option value="Sweden">Sweden</option>
<option value="England">England</option>
<option value="Germany">Germany</option>
<option value="USA">USA</option>
</select>
</div>
</div>
<div id="group2">
<div>
<select>
<option value="France">France</option>
<option value="Sweden">Sweden</option>
<option value="England">England</option>
<option value="Germany">Germany</option>
<option value="USA">USA</option>
</select>
</div>
<div>
<select>
<option value="France">France</option>
<option value="Sweden">Sweden</option>
<option value="England">England</option>
<option value="Germany">Germany</option>
<option value="USA">USA</option>
</select>
</div>
<div>
<select>
<option value="France">France</option>
<option value="Sweden">Sweden</option>
<option value="England">England</option>
<option value="Germany">Germany</option>
<option value="USA">USA</option>
</select>
</div>
</div>
$("select").change(function(){
var value = $(this).val();
$(this).closest('div').next('div').find("option").removeClass('hide');
$(this).closest('div').next('div').find("option[value='"+value+"']").addClass('hide');
});
UPDATED:
JSFiddle

add one class in your css
.hide{display:none;}
after that update your script function
$(this).closest('div').next('div').find("option").removeClass('hide');
$(this).closest('div').next('div').find("option[value='"+value+"']").addClass('hide');
In your code , you remove the element from the DOM using .remove()
if you need that element again you save that element in DOM.
I hope it will help you.

How to stop select box to use select2 plugin

i have many dropdowns in my page.
for dropdowns i am using select2 plugin.
i don't want to use select2 plugin for some of the dropdowns.
is there any way to do so?
i have searched on google and also have gone through their documentation but i didn't get anything related this.
this is my select box code ..
<div class="cust-input">
<select name="management[]">
<option value="0">Select Management</option>
<option value="Chairman">Chairman</option>
<option value="Vice Chairman">Vice Chairman</option>
<option value="Vice Chancellor">Vice Chancellor</option>
<option value="Secretary">Secretary</option>
<option value="Registrar">Registrar</option>
<option value="Dean">Dean</option>
<option value="Owner">Owner</option>
<option value="Other">Other</option>
</select>
</div>

You can implement that using specific class instead of common select tag element.
use:
$(".useSelect2").select2(); //either your desired name of your class or unique ID
instead of
$("select").select2(); // if you used this method, select2 will applied to all dropdowns.
Example:
<select name="management[]" class="useSelect2">
<option value="0">Select Management</option>
<option value="Chairman">Chairman</option>
<option value="Vice Chairman">Vice Chairman</option>
<option value="Vice Chancellor">Vice Chancellor</option>
<option value="Secretary">Secretary</option>
<option value="Registrar">Registrar</option>
<option value="Dean">Dean</option>
<option value="Owner">Owner</option>
<option value="Other">Other</option>
</select>
Javascript:
$(".useSelect2").select2();
Other dropdowns:
<select name="management[]" class="dontuseSelect2">
<option value="0">Select Management</option>
<option value="Chairman">Chairman</option>
<option value="Vice Chairman">Vice Chairman</option>
<option value="Vice Chancellor">Vice Chancellor</option>
<option value="Secretary">Secretary</option>
<option value="Registrar">Registrar</option>
<option value="Dean">Dean</option>
<option value="Owner">Owner</option>
<option value="Other">Other</option>
</select>

Put a class on the select elements you want to use select2 with, and then use that class to instantiate the plugin. Something like this:
$('.select2').select2();
<div class="cust-input">
<select name="management[]" class="select2">
<option value="0">Select Management</option>
<option value="Chairman">Chairman</option>
<option value="Vice Chairman">Vice Chairman</option>
<option value="Vice Chancellor">Vice Chancellor</option>
<option value="Secretary">Secretary</option>
<option value="Registrar">Registrar</option>
<option value="Dean">Dean</option>
<option value="Owner">Owner</option>
<option value="Other">Other</option>
</select>
<!-- this select will not be styled -->
<select>
<option>Foo</option>
<option>Bar</option>
</select>

Twitter bootstrap select picker add "Choose One"

Hi i'm using Bootstrap select, and i'm trying to add default option like Choose One
Here's my html code,
<div class="container">
<h3>Bootstrap Select</h3>
<select id="dataCombo" class="selectpicker">
<option data-hidden="true">Choose One</option>
<option value="one">One</option>
<option value="two">Two</option>
<option value="three">Three</option>
<option value="four">Four</option>
<option value="five">Five</option>
<option value="six">Six</option>
</select>
</div>
Also i'm using jqueryvalidation.org plugin for validation. On form submit above select option is not validating and i'm getting choose one if i print_r all posted data
Did anyone know where i'm going wrong ?

<div class="container">
<h3>Bootstrap Select</h3>
<select id="dataCombo" class="selectpicker">
<option value="" disabled selected>Choose One</option>
<option value="one">One</option>
<option value="two">Two</option>
<option value="three">Three</option>
<option value="four">Four</option>
<option value="five">Five</option>
<option value="six">Six</option>
</select>
</div>
Is this what you have wanted ...