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Jquery dynamic options hide/show in select box

I have following simple Html code with SELECT with the same class forms with identical options values
<select class="gr-fields-select">
<option value="">Select</option>
<option value="1042000018355">Product Management</option>
<option value="1042000018356">QA</option>
<option value="1042000018357">Sales</option>
</select>
<select class="gr-fields-select">
<option value="">Select</option>
<option value="1042000018355">Product Management</option>
<option value="1042000018356">QA</option>
<option value="1042000018357">Sales</option>
</select>
I just want to do click on a dropdown dynamic show and hide value from ALL SELECT with one class.
jQuery.each($("select.gr-fields-select"), function(){
$(".gr-fields-select").change(function() {
if($(".gr-fields-select").val() != "") {
$(".gr-fields-select option[value!="+$(".gr-fields-select").val()+"]").show();
$(".gr-fields-select option[value="+$(".gr-fields-select").val()+"]").hide();
} else {
$(".gr-fields-select option[value!="+$(".gr-fields-select").val()+"]").show();
}
});
})
Please check the jdfiddle here:
https://jsfiddle.net/mhassan94/d6j3fpt2/3/
If a select one dropdown value, they hide from All dropdown but if a change select dropdown value they show previous value and hide the new value in All dropdown.
How is that better to achieve?

Is this what you want to do?
$(".gr-fields-select").change(function(){
var selectedValue = $(this).val();
$(".gr-fields-select").each(function(ind, item){
if($(item).find(':selected').value!=selectedValue){
$(item).find('option').each(function(index,option){
if(option.value!=selectedValue){
$(option).show();
}else{
$(option).hide();
}
});
}
});
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<label>First</label><select class="gr-fields-select">
<option value="">Select</option>
<option value="1042000018355">Product Management</option>
<option value="1042000018356">QA</option>
<option value="1042000018357">Sales</option>
</select>
<br>
<label>Second</label><select class="gr-fields-select">
<option value="">Select</option>
<option value="1042000018355">Product Management</option>
<option value="1042000018356">QA</option>
<option value="1042000018357">Sales</option>
</select>
<br>
If you need to hide the value selected in one particular select element,from all the values populated in rest of the select elements try this,
$(".gr-fields-select").change(function(){
var selectedValue = $(this).val();
var previousValue = $(this).data("new");
if(previousValue!=undefined){
$(this).data("old",previousValue);
}
$(this).data("new",selectedValue);
$(".gr-fields-select").each(function(ind, item){
if($(item).find(':selected').value!=selectedValue){
$(item).find('option').each(function(index,option){
if(option.value==selectedValue){
$(option).hide();
}
if(option.value==previousValue){
$(option).show();
}
});
}
});
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<select class="gr-fields-select">
<option value="">Select</option>
<option value="1042000018355">Product Management</option>
<option value="1042000018356">QA</option>
<option value="1042000018357">Sales</option>
</select>
<select class="gr-fields-select">
<option value="">Select</option>
<option value="1042000018355">Product Management</option>
<option value="1042000018356">QA</option>
<option value="1042000018357">Sales</option>
</select>
<select class="gr-fields-select">
<option value="">Select</option>
<option value="1042000018355">Product Management</option>
<option value="1042000018356">QA</option>
<option value="1042000018357">Sales</option>
</select>

So in the don't re-invent the wheel category. I'm thinking a multi select such as select2 might accomplish what you want alot easier than the multiple drop downs. select 2 even lets you limit your selection length if you only want two. I think with multiple drop downs there is alot to track. especially if you want more than two drop downs. What if they choose the selects out of order? run the snippet below to see a possible implementation using a multiselect
$(document).ready(
function () {
$("#multipleSelectExample").select2({
maximumSelectionLength: 2,
closeOnSelect: false,
allowClear: true
});
}
);
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src=
"https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.12/js/select2.full.min.js">
</script>
<link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.12/css/select2.min.css">
<select id="multipleSelectExample" data-placeholder="Select" multiple>
<option value="1042000018355">Product Management</option>
<option value="1042000018356">QA</option>
<option value="1042000018357">Sales</option>
</select>

Array of select field with same name and different id.

I have an array of select fields all having the same list of option value. What i am trying to get is, if a value is selected in any of the field, it should not show on the other. Below is an example code. For example, if I am having four select fields, if I select 'a' on first field, the value "a" should not appear on the next select field. Same with other values of "b", "c" and "d".
I am trying to use java script for the same. I am in learning phase. help will be really appreciated. Thanks
<select name='list' id='list_1'>
<option value='a'>a</option>
<option value='b'>b</option>
<option value='c'>c</option>
<option value='d'>d</option>
</select>
<select name='list' id='list_2'>
<option value='b'>b</option>
<option value='c'>c</option>
<option value='d'>d</option>
</select>
<select name='list' id='list_3'>
<option value='c'>c</option>
<option value='d'>d</option>
</select>
<select name='list' id='list_4'>
<option value='d'>d</option>
</select>

Try this code that i have written .. Hope should help
<select>
<option value="0"> </option>
<option value="1">a</option>
<option value="2">b</option>
<option value="3">c</option>
</select>
<select>
<option value="0"> </option>
<option value="1">a</option>
<option value="2">b</option>
<option value="3">c</option>
</select>
<select>
<option value="0"> </option>
<option value="1">a</option>
<option value="2">b</option>
<option value="3">c</option>
</select>
$(document).on('change', 'select', function() {
$(this).find('option:selected').addClass('keepit');
$('option[value="' + this.value + '"]:not( .keepit)').remove();
});
https://jsfiddle.net/av46dbo1/

Since you don't want to destroy the data, you need to hide the options.
That's tricky because you have multiple state to combine.
you can make several IF comparisons, hard-code a table of combos for each group and options (yuck), or use a mountain of JS to solve this, but i think that CSS is better.
A simple way to accomplish this is to use CSS; multiple classes on a single element that translate your many states into rules that can be applied instantly and generically (without hard-coding ids or names).
<select name='list' id='list_1'>
<option value='a'>a</option> <option value='b'>b</option>
<option value='c'>c</option> <option value='d'>d</option>
</select>
<select name='list' id='list_2'>
<option value='a'>a</option> <option value='b'>b</option>
<option value='c'>c</option> <option value='d'>d</option>
</select>
<select name='list' id='list_3'>
<option value='a'>a</option> <option value='b'>b</option>
<option value='c'>c</option> <option value='d'>d</option>
</select>
<select name='list' id='list_4'>
<option value='a'>a</option> <option value='b'>b</option>
<option value='c'>c</option> <option value='d'>d</option>
</select>
<script src='//maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js'></script>
<script>
var combos=[], // store the css we need to define hide/show rules
classes= new Array($("select").length); //a place to store many states
$("select").each(function(i,e){ // for every drop down,
$(this).change(function(){ // when it changes:
classes[i]=this.value; // update array with changed value in right slot
document.body.className=classes.join(" "); // update body class with array
});
});
$("select option[value]").each(function(n, a){ // make css to hide each option if body has the same class:
combos.push( "body."+a.value+" option[value='"+a.value+"'] ");
});
//append the dynamic CSS to the head:
$("head").append("<style> "+combos+"{ display: none; }</style>");
</script>
online demo: http://pagedemos.com/pe2uf5vkx9vh/
if you want to restrict this functionality to certain drop downs, give them a class like <select class=hider and change $("select to $("select.hider in the code above.
if you have values with spaces, you'll need fancier CSS selectors than class, like data-state="|a b|hello world|honda crv|" attribs that you can delimit and hit with partial attribute selectors (body[data-state*='|hello world|']...), but the same pattern can work with many and more complex states.

Fiddle
$(function(){
$('#list_1').change(function(){
var valueToRemove=$(this).val();
$('select').not('#list_1').each(function(){
var currentId=$(this).prop('id');
$("#"+currentId+" option[value="+valueToRemove+"]").remove();
})
})
})

Check if option is selected appear an other option value

I have something like :
<select id="BanReason">
<option value="hack">Hack</option>
<option value="badlang">Bad Language</option>
<option value="scrammer">Scrammer</option>
</select>
<select id="BanLength">
<option value="1day">1 Day</option>
<option value="2days">3 Days</option>
<option value="1week">1 Week</option>
</select>
I am trying to do, if Scrammer is selected in #BadReason select 1 week in #BanLength automaticly. 

try using change event BanReason and based on this value pass the desired value to BanLength and trigger the change.:
$("#BanReason").on("change",function(){
if(this.value == "scrammer"){
$("#BanLength").val("1week").trigger("change");
}
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<select id="BanReason">
<option value="hack">Hack</option>
<option value="badlang">Bad Language</option>
<option value="scrammer">Scrammer</option>
</select>
<select id="BanLength">
<option value="1day">1 Day</option>
<option value="2days">3 Days</option>
<option value="1week">1 Week</option>
</select>

On change event will help you to do this
$("#BanReason").on("change",function(){
if($(this).val() == "scrammer")
$("#BanLength").val("1week");
});
Added a Fiddle to this
Fiddle

How can I move a select element's values & text to another select element

I want to get the <option> values and text from a <select> element #myselect, and add it to another <select> element #newselect. The value and text passed to the second select element, #newselect, must also be disabled. I'd like support for IE 8+.
<select id="myselect">
<option value="1">Red</option>
<option value="2">Orange</option>
<option value="3">Yellow</option>
</select>
Take the above, disable them and add them to the below:
<select id="newselect">
<option value="1">Green</option>
<option value="2">Blue</option>
<option disabled value="1">Red</option>
<option disabled value="2">Orange</option>
<option disabled value="3">Yellow</option>
</select>

Since you included the jQuery tag, here's a jQuery solution.
As long as you're using jQuery 1.x, IE8 support is included.
$('#myselect option').each(
function() {
$(this).prop('disabled', true).appendTo('#newselect');
}
);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<select id="myselect">
<option value="1">Red</option>
<option value="2">Orange</option>
<option value="3">Yellow</option>
</select>
<select id="newselect">
<option value="1">Green</option>
<option value="2">Blue</option>
</select>

You already have jQuery answer. So now if you are curious how it can be in pure javascript, here it is. As you can see, it's a little more verbose of course:
var mySelect = document.getElementById('myselect'),
newSelect = document.getElementById('newselect');
while (mySelect.options.length) {
mySelect.options[0].disabled = true;
newSelect.add(mySelect.options[0]);
}
<select id="myselect">
<option value="1">Red</option>
<option value="2">Orange</option>
<option value="3">Yellow</option>
</select>
<select id="newselect">
<option value="1">Green</option>
<option value="2">Blue</option>
</select>

Links in <select> dropdown options

Is it possible for each dropdown options to link somewhere when selected without the need for an external button?
<select>
<option value="x">x</option>
<option value="y">y</option>
</select>

You can use the onChange property. Something like:
<select onChange="window.location.href=this.value">
<option value="www.google.com">A</option>
<option value="www.aol.com">B</option>
</select>

Add an onchange event handler and set the pages location to the value
<select id="foo">
<option value="">Pick a site</option>
<option value="http://www.google.com">x</option>
<option value="http://www.yahoo.com">y</option>
</select>
<script>
document.getElementById("foo").onchange = function() {
if (this.selectedIndex!==0) {
window.location.href = this.value;
}
};
</script>

... or if you want / need to keep your option 'value' as it was, just add a new attribute:
<select id="my_selection">
<option value="x" href="/link/to/somewhere">value 1</option>
<option value="y" href="/link/to/somewhere/else">value 2</option>
</select>
<script>
document.getElementById('my_selection').onchange = function() {
window.location.href = this.children[this.selectedIndex].getAttribute('href');
}
</script>

Maybe this will help:
<select onchange="location = this.value;">
<option value="home.html">Home</option>
<option value="contact.html">Contact</option>
<option value="about.html">About</option>
</select>

This is an old question, I know but for 2019 peeps:
Like above if you just want to change the URL you can do this:
<select onChange="window.location.href=this.value">
<option value="www.google.com">A</option>
<option value="www.aol.com">B</option>
</select>
But if you want it to act like an a tag and so you can do "./page", "#bottom" or "?a=567" use window.location.replace()
<select onChange="window.location.redirect(this.value)">
<option value="..">back</option>
<option value="./list">list</option>
<option value="#bottom">bottom</option>
</select>

Extending on #kevin's answer,
if someone has to perform some confirmation logic if URL is critical.
<select onChange=" this.options[this.selectedIndex].text == 'Delete' ? "Confirmation logic" : window.location.href=this.value;" >
<option selected disabled>Action</option>
<option value="/user/view">View</option>
<option value="/user/edit">Edit</option>
<option value="/user/delete">Delete</option>
</select>

You can use this code:
<select id="menu" name="links" size="1" onchange="window.location.href=this.value;">
<option value="URL">Book</option>
<option value="URL">Pen</option>
<option value="URL">Read</option>
<option value="URL">Apple</option>
</select>