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Car Make/Model dynamic dropdown

I'm setting up a new form on my site, and I'm using some code I found here (Vehicle drop down selector). However, I'm using this code within a form, and once the form is submitted, the values for make/model aren't changed to their respective names, instead showing their form values. Being a complete JS noob, how would I go about changing the values submitted from values to make/model names?
$(document).ready(function() {
var $make = $('#make'),
$model = $('#model'),
$options = $model.find('option');
$make.on('change', function() {
$model.html($options.filter('[value="' + this.value + '"]'));
$model.trigger('change');
}).trigger('change');
var $model = $('#model'),
$year = $('#year'),
$yearOptions = $year.find('option');
$model.on('change', function() {
$year.html($yearOptions.filter('[value="' + this.value + '"]'));
$year.trigger('change');
}).trigger('change');
var $year = $('#year'),
$identifier = $('#identifier'),
$identifierOptions = $identifier.find('option');
$year.on('change', function() {
var filteredIdetifiers = $identifierOptions.filter('[value="' + this.value + '"]');
debugger
if (!($("#make").val() == 3 && $("#model option:selected").text() == 'Falcon')) {
filteredIdetifiers = filteredIdetifiers.filter(function(i, e) {
return e.value !== '3'
});
}
$identifier.html(filteredIdetifiers);
$identifier.trigger('change');
}).trigger('change');
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<!-- Vehicle Brand Selector List -->
<select name="make" id="make">
<option value="0">Make</option>
<option value="1">BMW</option>
<option value="2">Daewoo</option>
<option value="3">Ford</option>
<option value="4">Holden</option>
<option value="5">Honda</option>
<option value="6">Hyundai</option>
<option value="7">Isuzu</option>
<option value="8">Kia</option>
<option value="9">Lexus</option>
<option value="10">Mazda</option>
<option value="11">Mitsubishi</option>
<option value="12">Nissan</option>
<option value="13">Peugeot</option>
<option value="14">Subaru</option>
<option value="15">Suzuki</option>
<option value="16">Toyota</option>
<option value="17">Volkswagen</option>
</select>
<!-- Vehicle Model List -->
<select name="model" id="model">
<option value="0">Model</option>
<option class="318i" value="1">318i</option>
<option class="lanos" value="2">Lanos</option>
<option class="courier" value="3">Courier</option>
<option class="falcon" value="3">Falcon</option>
<option class="festiva" value="3">Festiva</option>
<option class="fiesta" value="3">Fiesta</option>
<option class="focus" value="3">Focus</option>
<option class="laser" value="3">Laser</option>
<option class="ranger" value="3">Ranger</option>
<option class="territory" value="3">Territory</option>
<option class="astra" value="4">Astra</option>
<option class="barina" value="4">Barina</option>
<option class="captiva" value="4">Captiva</option>
<option class="colorado" value="4">Colorado</option>
<option class="commodore" value="4">Commodore</option>
<option class="cruze" value="4">Cruze</option>
<option class="rodeo" value="4">Rodeo</option>
<option class="viva" value="4">Viva</option>
</select>
<!-- Vehicle Year List -->
<select name="year" id="year">
<option value="0">Year</option>
<option value="1">1998</option>
<option value="1">1999</option>
<option value="1">2000</option>
<option value="1">2001</option>
<option value="1">2002</option>
<option value="1">2003</option>
<option value="1">2004</option>
<option value="1">2005</option>
<option value="2">1997</option>
<option value="2">1998</option>
<option value="2">1999</option>
<option value="2">2000</option>
<option value="2">2001</option>
<option value="2">2002</option>
<option value="2">2003</option>
<option value="3">1991-1999</option>
<option value="4">1997-2007</option>
<option value="5">1997-2007</option>
<option value="3">2002</option>
<option value="3">2003</option>
<option value="3">2004</option>
<option value="3">2005</option>
<option value="4">1997-2005</option>
<option value="4">1997-2005</option>
<option value="4">1997-2005</option>
<option value="4">1997-2005</option>
<option value="4">1997-2005</option>
<option value="4">1997-2005</option>
<option value="4">1997-2005</option>
<option value="4">1997-2005</option>
</select>
<!-- Vehicle Identity List -->
<select name="identifier" id="identifier">
<option value="0">Type</option>
<option class="E46" value="1">E46</option>
<option class="1997-2003" value="2">N/A</option>
<option class="1997-2007" value="4">N/A</option>
<option class="1997-2007" value="5">N/A</option>
<option class="5041618" value="3">BA</option>
<option class="1997-2005" value="3">AU</option>
<option class="1997-2005" value="3">AU2</option>
<option class="1997-2005" value="4">N/A</option>
<option class="1997-2005" value="4">1997-2005</option>
<option class="1997-2005" value="4">1997-2005</option>
<option class="1997-2005" value="4">1997-2005</option>
<option class="1997-2005" value="4">1997-2005</option>
<option class="1997-2005" value="4">1997-2005</option>
</select>

In every <option> tag there is an attribute called value. This value attribute is what is returned at as the value of the dropdown when that option is selected. Seems like in the code you found they are all simply set to numbers. You can set them to be whatever you want though:
<option value="Ford">Ford</option>
<option class="focus" value="Focus">Focus</option>
FIXING DYNAMIC OPTIONS
I see that modifying the values directly affect how the dynamic options are displayed. For example the value attribute of the car model dropdown is used to filter the car make dropdown by only displaying options with the same value. Instead of using the model dropdown's value attributes to compare with make, we can add a new data- attribute called data-make and filter the model dropdown based on that instead. This allows you to freely modify the value attribute in model. The example code below shows this. You would need to modify your JS so model affects year, and year affects identifier in the same way.
$(document).ready(function() {
var $make = $('#make'),
$model = $('#model'),
$options = $model.find('option');
$make.on('change', function() {
// We now filter model using the data-make attribute, not value
$model.html($options.filter('[data-make="' + this.value + '"]'));
$model.trigger('change');
}).trigger('change');
$('#carForm').submit(function(e) {
e.preventDefault();
let formData = $(this).serializeArray();
let data = {};
for (let i = 0; i < formData.length; i++) {
data[formData[i].name] = formData[i].value;
}
alert('Make: ' + data.make + '\nModel: ' + data.model);
});
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form id="carForm">
<select name="make" id="make">
<option value="0">Make</option>
<option value="BMW">BMW</option> <!-- These values are now make names -->
<option value="Daewoo">Daewoo</option>
<option value="Ford">Ford</option>
</select>
<!-- Vehicle Model List -->
<!-- Notice the new "data-make" attributes for each -->
<select name="model" id="model">
<option value="0">Model</option>
<option class="318i" value="318i" data-make="BMW">318i</option>
<option class="lanos" value="Lanos" data-make="Daewoo">Lanos</option>
<option class="courier" value="Courier" data-make="Ford">Courier</option>
<option class="falcon" value="Falcon" data-make="Ford">Falcon</option>
<option class="festiva" value="Festiva" data-make="Ford">Festiva</option>
<option class="fiesta" value="Fiesta" data-make="Ford">Fiesta</option>
<option class="focus" value="Focus" data-make="Ford">Focus</option>
</select>
<button type="submit">Submit</button>
</form>

You can get the selected option text like this.
$('#form').submit(function(e) {
e.preventDefault();
var make = $make.find(':selected').text();
}
But it would be good practice to set the value you expect to return as the option value and use a data attribute or class to handle the filtering logic.

how to display options of select tag [duplicate]

This question already has answers here:
How can you programmatically tell an HTML SELECT to drop down (for example, due to mouseover)?
(16 answers)
Closed 3 years ago.
Is it possible to use JavaScript to open an HTML select to show its option list?

Unfortunately there's a simple answer to this question, and it's "No"

I had this problem...and found a workable solution.
I didn't want the select box to show until the user clicked on some plain HTML. So I overlayed the select element with opacity=.01. Upon clicking, I changed it back to opacity=100. This allowed me to hide the select, and when the user clicked the text the select appeared with the options showing.

I use this... but it requires the user to click on the select box...
Here are the 2 javascript functions
function expand(obj)
{
obj.size = 5;
}
function unexpand(obj)
{
obj.size = 1;
}
then i create the select box
<select id="test" multiple="multiple" name="foo" onFocus="expand(this)" onBlur="unexpand(this)">
<option >option1</option>
<option >option2</option>
<option >option3</option>
<option >option4</option>
<option >option5</option>
</select>
I know this code is a little late, but i hope it helps someone who had the same problem as me.
ps/fyi
i have not tested the code above (i create my select box dynamically), and the code i did write was only tested in FireFox.

This works on Google Chrome
dropDown = function (elementId) {
var dropdown = document.getElementById(elementId);
try {
showDropdown(dropdown);
} catch(e) {
}
return false;
};
showDropdown = function (element) {
var event;
event = document.createEvent('MouseEvents');
event.initMouseEvent('mousedown', true, true, window);
element.dispatchEvent(event);
};

After trying to solve this issue for some time, I managed to come with a working solution that is also valid:
var event = new MouseEvent('mousedown');
element.dispatchEvent(event);
I've tried to implement this in Jquery as well, using trigger and mousedown or only mousedown but with no success.

This is very late, but I thought it could be useful to someone should they reference this question. I beleive the below JS will do what is asked.
<script>
$(document).ready(function()
{
document.getElementById('select').size=3;
});
</script>

I'm fairly certain the answer is: No. You can select options with JavaScript but not open the select. You'd have to use a custom solution.

The solution I present is safe, simple and compatible with Internet Explorer, FireFox and Chrome.
This approach is new and complete. I not found nothing equal to that solution on the internet. Is simple, cross-browser (Internet Explorer, Chrome and Firefox), preserves the layout, use the select itself and is easy to use.
Note: JQuery is required.
HTML CODE
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>CustonSelect</title>
<script type="text/javascript" src="./jquery-1.3.2.js"></script>
<script type="text/javascript" src="./CustomSelect.js"></script>
</head>
<div id="testDiv"></div>
<body>
<table>
<tr>
<td>
<select id="Select0" >
<option value="0000">0000</option>
<option value="0001">0001</option>
<option value="0002">0002</option>
<option value="0003">0003</option>
<option value="0004">0004</option>
<option value="0005">0005</option>
<option value="0006">0006</option>
<option value="0007">0007</option>
<option value="0008">0008</option>
<option value="0009">0009</option>
<option value="0010">0010</option>
<option value="0011">0011</option>
<option value="0012">0012</option>
<option value="0013">0013</option>
<option value="0014">0014</option>
<option value="0015">0015</option>
<option value="0016">0016</option>
<option value="0017">0017</option>
<option value="0018">0018</option>
<option value="0019">0019</option>
<option value="0020">0020</option>
<option value="0021">0021</option>
<option value="0022">0022</option>
<option value="0023">0023</option>
<option value="0024">0024</option>
<option value="0025">0025</option>
<option value="0026">0026</option>
<option value="0027">0027</option>
<option value="0028">0028</option>
<option value="0029">0029</option>
<option value="0030">0030</option>
<option value="0031">0031</option>
<option value="0032">0032</option>
<option value="0033">0033</option>
<option value="0034">0034</option>
<option value="0035">0035</option>
<option value="0036">0036</option>
<option value="0037">0037</option>
<option value="0038">0038</option>
<option value="0039">0039</option>
<option value="0040">0040</option>
</select>
</td>
</tr>
<tr>
<td>
<select id="Select1" >
<option value="0000">0000</option>
<option value="0001">0001</option>
<option value="0002">0002</option>
<option value="0003">0003</option>
<option value="0004">0004</option>
<option value="0005">0005</option>
<option value="0006">0006</option>
<option value="0007">0007</option>
<option value="0008">0008</option>
<option value="0009">0009</option>
<option value="0010">0010</option>
<option value="0011">0011</option>
<option value="0012">0012</option>
<option value="0013">0013</option>
<option value="0014">0014</option>
<option value="0015">0015</option>
<option value="0016">0016</option>
<option value="0017">0017</option>
<option value="0018">0018</option>
<option value="0019">0019</option>
<option value="0020">0020</option>
<option value="0021">0021</option>
<option value="0022">0022</option>
<option value="0023">0023</option>
<option value="0024">0024</option>
<option value="0025">0025</option>
<option value="0026">0026</option>
<option value="0027">0027</option>
<option value="0028">0028</option>
<option value="0029">0029</option>
<option value="0030">0030</option>
<option value="0031">0031</option>
<option value="0032">0032</option>
<option value="0033">0033</option>
<option value="0034">0034</option>
<option value="0035">0035</option>
<option value="0036">0036</option>
<option value="0037">0037</option>
<option value="0038">0038</option>
<option value="0039">0039</option>
<option value="0040">0040</option>
</select>
</td>
</tr>
<tr>
<td>
<select id="Select2" >
<option value="0000">0000</option>
<option value="0001">0001</option>
<option value="0002">0002</option>
<option value="0003">0003</option>
<option value="0004">0004</option>
<option value="0005">0005</option>
<option value="0006">0006</option>
<option value="0007">0007</option>
<option value="0008">0008</option>
<option value="0009">0009</option>
<option value="0010">0010</option>
<option value="0011">0011</option>
<option value="0012">0012</option>
<option value="0013">0013</option>
<option value="0014">0014</option>
<option value="0015">0015</option>
<option value="0016">0016</option>
<option value="0017">0017</option>
<option value="0018">0018</option>
<option value="0019">0019</option>
<option value="0020">0020</option>
<option value="0021">0021</option>
<option value="0022">0022</option>
<option value="0023">0023</option>
<option value="0024">0024</option>
<option value="0025">0025</option>
<option value="0026">0026</option>
<option value="0027">0027</option>
<option value="0028">0028</option>
<option value="0029">0029</option>
<option value="0030">0030</option>
<option value="0031">0031</option>
<option value="0032">0032</option>
<option value="0033">0033</option>
<option value="0034">0034</option>
<option value="0035">0035</option>
<option value="0036">0036</option>
<option value="0037">0037</option>
<option value="0038">0038</option>
<option value="0039">0039</option>
<option value="0040">0040</option>
</select>
</td>
</tr>
<tr>
<td>
<select id="Select3" >
<option value="0000">0000</option>
<option value="0001">0001</option>
<option value="0002">0002</option>
<option value="0003">0003</option>
<option value="0004">0004</option>
<option value="0005">0005</option>
<option value="0006">0006</option>
<option value="0007">0007</option>
<option value="0008">0008</option>
<option value="0009">0009</option>
<option value="0010">0010</option>
<option value="0011">0011</option>
<option value="0012">0012</option>
<option value="0013">0013</option>
<option value="0014">0014</option>
<option value="0015">0015</option>
<option value="0016">0016</option>
<option value="0017">0017</option>
<option value="0018">0018</option>
<option value="0019">0019</option>
<option value="0020">0020</option>
<option value="0021">0021</option>
<option value="0022">0022</option>
<option value="0023">0023</option>
<option value="0024">0024</option>
<option value="0025">0025</option>
<option value="0026">0026</option>
<option value="0027">0027</option>
<option value="0028">0028</option>
<option value="0029">0029</option>
<option value="0030">0030</option>
<option value="0031">0031</option>
<option value="0032">0032</option>
<option value="0033">0033</option>
<option value="0034">0034</option>
<option value="0035">0035</option>
<option value="0036">0036</option>
<option value="0037">0037</option>
<option value="0038">0038</option>
<option value="0039">0039</option>
<option value="0040">0040</option>
</select>
</td>
</tr>
<tr>
<td>
<select id="Select4" >
<option value="0000">0000</option>
<option value="0001">0001</option>
<option value="0002">0002</option>
<option value="0003">0003</option>
<option value="0004">0004</option>
<option value="0005">0005</option>
<option value="0006">0006</option>
<option value="0007">0007</option>
<option value="0008">0008</option>
<option value="0009">0009</option>
<option value="0010">0010</option>
<option value="0011">0011</option>
<option value="0012">0012</option>
<option value="0013">0013</option>
<option value="0014">0014</option>
<option value="0015">0015</option>
<option value="0016">0016</option>
<option value="0017">0017</option>
<option value="0018">0018</option>
<option value="0019">0019</option>
<option value="0020">0020</option>
<option value="0021">0021</option>
<option value="0022">0022</option>
<option value="0023">0023</option>
<option value="0024">0024</option>
<option value="0025">0025</option>
<option value="0026">0026</option>
<option value="0027">0027</option>
<option value="0028">0028</option>
<option value="0029">0029</option>
<option value="0030">0030</option>
<option value="0031">0031</option>
<option value="0032">0032</option>
<option value="0033">0033</option>
<option value="0034">0034</option>
<option value="0035">0035</option>
<option value="0036">0036</option>
<option value="0037">0037</option>
<option value="0038">0038</option>
<option value="0039">0039</option>
<option value="0040">0040</option>
</select>
</td>
</tr>
</table>
<input type="button" id="Button0" value="MoveLayout!"/>
</body>
</html>
JAVASCRIPT CODE
var customSelectFields = new Array();
// Note: The list of selects to be modified! By Questor
customSelectFields[0] = "Select0";
customSelectFields[1] = "Select1";
customSelectFields[2] = "Select2";
customSelectFields[3] = "Select3";
customSelectFields[4] = "Select4";
$(document).ready(function()
{
//Note: To debug! By Questor
$("#Button0").click(function(event){ AddTestDiv(); });
StartUpCustomSelect(null);
});
//Note: To test! By Questor
function AddTestDiv()
{
$("#testDiv").append("<div style=\"width:100px;height:100px;\"></div>");
}
//Note: Startup selects customization scheme! By Questor
function StartUpCustomSelect(what)
{
for (i = 0; i < customSelectFields.length; i++)
{
$("#" + customSelectFields[i] + "").click(function(event){ UpCustomSelect(this); });
$("#" + customSelectFields[i] + "").wrap("<div id=\"selectDiv_" + customSelectFields[i] + "\" onmouseover=\"BlockCustomSelectAgain();\" status=\"CLOSED\"></div>").parent().after("<div id=\"coverSelectDiv_" + customSelectFields[i] + "\" onclick=\"UpOrDownCustomSelect(this);\" onmouseover=\"BlockCustomSelectAgain();\"></div>");
//Note: Avoid breaking the layout when the CSS is modified from "position" to "absolute" on the select! By Questor
$("#" + customSelectFields[i] + "").parent().css({'width': $("#" + customSelectFields[i] + "")[0].offsetWidth + 'px', 'height': $("#" + customSelectFields[i] + "")[0].offsetHeight + 'px'});
BlockCustomSelect($("#" + customSelectFields[i] + ""));
}
}
//Note: Repositions the div that covers the select using the "onmouseover" event so
//Note: if element on the screen move the div always stand over it (recalculate! By Questor
function BlockCustomSelectAgain(what)
{
for (i = 0; i < customSelectFields.length; i++)
{
if($("#" + customSelectFields[i] + "").parent().attr("status") == "CLOSED")
{
BlockCustomSelect($("#" + customSelectFields[i] + ""));
}
}
}
//Note: Does not allow the select to be clicked or clickable! By Questor
function BlockCustomSelect(what)
{
var coverSelectDiv = $(what).parent().next();
//Note: Ensures the integrity of the div style! By Questor
$(coverSelectDiv).removeAttr('style');
//Note: To resolve compatibility issues! By Questor
var backgroundValue = "";
var filerValue = "";
if(navigator.appName == "Microsoft Internet Explorer")
{
backgroundValue = 'url(fakeimage)';
filerValue = 'progid:DXImageTransform.Microsoft.AlphaImageLoader(enabled=true, sizingMethod=\'scale\', src=\'fakeimage\' )';
}
//Note: To debug! By Questor
//'border': '5px #000 solid',
$(coverSelectDiv).css({
'position': 'absolute',
'top': $(what).offset().top + 'px',
'left': $(what).offset().left + 'px',
'width': $(what)[0].offsetWidth + 'px',
'height': $(what)[0].offsetHeight + 'px',
'background': backgroundValue,
'-moz-background-size':'cover',
'-webkit-background-size':'cover',
'background-size':'cover',
'filer': filerValue
});
}
//Note: Allow the select to be clicked or clickable! By Questor
function ReleaseCustomSelect(what)
{
var coverSelectDiv = $(what).parent().next();
$(coverSelectDiv).removeAttr('style');
$(coverSelectDiv).css({'display': 'none'});
}
//Note: Open the select! By Questor
function DownCustomSelect(what)
{
//Note: Avoid breaking the layout. Avoid that select events be overwritten by the others! By Questor
$(what).css({
'position': 'absolute',
'z-index': '100'
});
//Note: Open dropdown! By Questor
$(what).attr("size","10");
ReleaseCustomSelect(what);
//Note: Avoids the side-effect of the select loses focus.! By Questor
$(what).focus();
//Note: Allows you to select elements using the enter key when the select is on focus! By Questor
$(what).keyup(function(e){
if(e.keyCode == 13)
{
UpCustomSelect(what);
}
});
//Note: Closes the select when loses focus! By Questor
$(what).blur(function(e){
UpCustomSelect(what);
});
$(what).parent().attr("status", "OPENED");
}
//Note: Close the select! By Questor
function UpCustomSelect(what)
{
$(what).css("position","static");
//Note: Close dropdown! By Questor
$(what).attr("size","1");
BlockCustomSelect(what);
$(what).parent().attr("status", "CLOSED");
}
//Note: Closes or opens the select depending on the current status! By Questor
function UpOrDownCustomSelect(what)
{
var customizedSelect = $($(what).prev().children()[0]);
if($(what).prev().attr("status") == "CLOSED")
{
DownCustomSelect(customizedSelect);
}
else if($(what).prev().attr("status") == "OPENED")
{
UpCustomSelect(customizedSelect);
}
}

<select id="myDropDown">
<option>html5</option>
<option>javascript</option>
<option>jquery</option>
<option>css</option>
<option>sencha</option>
</select>
By jQuery:
var myDropDown=$("#myDropDown");
var length = $('#myDropDown> option').length;
//open dropdown
myDropDown.attr('size',length);
//close dropdown
myDropDown.attr('size',0);
By javascript:
var myDropDown=document.getElementById("myDropDown");
var length = myDropDown.options.length;
//open dropdown
myDropDown.size = length;
//close dropdown
myDropDown.size = 0;
Copied from:
Open close select

//use jquery
$select.trigger('mousedown')

SumoSelect not selecting all values in array

I am using SumoSelect. I have an array of values to be selected.
var physicianIds = [10,11,12,13];
This is the html:
<select class="form-control SumoUnder" id="PhysicianID" multiple="multiple" name="CycleDetails.ProcedureRoomPhysicianIds">
<option value="1">MD01</option>
<option value="10">MD10</option>
<option value="11">MD11</option>
<option value="12">MD12</option>
<option value="13">MD13</option>
<option value="14">MD14</option>
<option value="15">MD15</option>
<option value="16">MD16</option>
<option value="17">MD17</option>
<option value="18">MD18</option>
<option disabled="disabled" value="19">MD19</option>
<option value="2">MD02</option>
<option disabled="disabled" value="20">MD20</option>
<option value="3">MD03</option>
<option value="4">MD04</option>
<option value="5">MD05</option>
<option value="6">MD06</option>
<option value="7">MD07</option>
<option value="8">MD08</option>
<option value="9">MD09</option>
</select>
My js:
$(document).ready(function () {
$('#PhysicianID').SumoSelect();
for (var i = 0; i < window.physicianIds.length; i++) {
var physicianId = window.physicianIds[i];
$('#PhysicianID')[0].sumo.selectItem(physicianId);
}
});
According to SumoSelect documentation, I would expect the following to be selected:
MD10, MD11, MD12, and MD13
However, only MD02 and MD03 are being selected -- what am I missing here?

According to documentation you have to use string to select an item by value. integer selects items by index.
$('#PhysicianID').SumoSelect();
var physicianIds = [10, 11, 12, 13];
for (var j = 0; j < physicianIds.length; j++) {
var physicianId = physicianIds[j].toString();
$('#PhysicianID')[0].sumo.selectItem(physicianId);
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery.sumoselect/3.0.2/jquery.sumoselect.min.js"></script>
<link href="https://cdnjs.cloudflare.com/ajax/libs/jquery.sumoselect/3.0.2/sumoselect.min.css" rel="stylesheet"/>
<select class="form-control SumoUnder" id="PhysicianID" multiple="multiple" name="CycleDetails.ProcedureRoomPhysicianIds">
<option value="1">MD01</option>
<option value="10">MD10</option>
<option value="11">MD11</option>
<option value="12">MD12</option>
<option value="13">MD13</option>
<option value="14">MD14</option>
<option value="15">MD15</option>
<option value="16">MD16</option>
<option value="17">MD17</option>
<option value="18">MD18</option>
<option disabled="disabled" value="19">MD19</option>
<option value="2">MD02</option>
<option disabled="disabled" value="20">MD20</option>
<option value="3">MD03</option>
<option value="4">MD04</option>
<option value="5">MD05</option>
<option value="6">MD06</option>
<option value="7">MD07</option>
<option value="8">MD08</option>
<option value="9">MD09</option>
</select>

Alert when selecting some particular value from drop down in JavaScript

Below are the dropdown data..
<select size="1" name="Test_Data">
<option selected value="Select One">Select One</option>
<option value="Data1">IN-Data1</option>
<option value="Data2">IN-Data2</option>
<option value="Data3">IN-Data3</option>
<option value="Data4">AUS-Data4</option>
<option value="Data5">AUS-Data5</option>
<option value="Data6">US-Data6</option>
<option value="Data7">US-Data7</option>
I want to get alert/pop up when I select the data which is start from IN in drop down list.

Try this:
https://jsfiddle.net/mminetto/bggwnkwj/
var select = $('select[name="Test_Data"]');
select.on('change', function(){
var options = select.children('option:selected');
if(options.length > 0 && options[0].innerText.startsWith("IN")){
alert(this.value);
alert(options[0].innerText);
}
});

<select size="1" name="Test_Data" id="dropdown">
<option selected value="Select One">Select One</option>
<option value="Data1">IN-Data1</option>
<option value="Data2">IN-Data2</option>
<option value="Data3">IN-Data3</option>
<option value="Data4">AUS-Data4</option>
<option value="Data5">AUS-Data5</option>
<option value="Data6">US-Data6</option>
<option value="Data7">US-Data7</option>
in javascript
<script>
$("#dropdown").change(function(){
if($(this).find("option:selected").text().startsWith("IN")){
alert("option with IN selected =>"+$(this).find("option:selected").text());
}
});
</script>

Try this code
HTML
<select size="1" onChange="showAlert()" id="dataCountry" name="Test_Data">
<option selected value="Select One">Select One</option>
<option value="Data1">IN-Data1</option>
<option value="Data2">IN-Data2</option>
<option value="Data3">IN-Data3</option>
<option value="Data4">AUS-Data4</option>
<option value="Data5">AUS-Data5</option>
<option value="Data6">US-Data6</option>
<option value="Data7">US-Data7</option>
</select>
JavaScript
<script>
function showAlert() {
var el = document.getElementById('dataCountry'); // get the index
var text = el.options[el.selectedIndex].innerHTML; // get the label
var n = text.search("IN"); //search number of IN
if(n>=0) {
alert(text);
}
}
</script>

Hide/show the selected option on a secondary select

I have two <select> elements with different IDs.
When the user selects a value from the first select box, I want the second select box to only display connected values.
My code:
<select id="ExtraField_1" name="ExtraField_1">
<option value="1">test1</option>
<option value="2">test2</option>
<option value="3">test3</option>
<option value="4">test4</option>
<option value="5">test5</option>
<option value="6">test6</option>
<option value="7">test7</option>
<option value="8">test8</option>
<option value="9">test9</option>
<option value="10">test10</option>
<option value="11">test11</option>
<option value="12">test12</option>
</select>
<select id="ExtraField_2" name="ExtraField_2">
<option value="1">test1</option>
<option value="2">test2</option>
<option value="3">test3</option>
<option value="4">test4</option>
<option value="5">test5</option>
<option value="6">test6</option>
<option value="7">test7</option>
<option value="8">test8</option>
<option value="9">test9</option>
<option value="10">test10</option>
<option value="11">test11</option>
<option value="12">test12</option>
<option value="13">test13</option>
<option value="14">test14</option>
<option value="15">test15</option>
<option value="16">test16</option>
<option value="17">test17</option>
<option value="18">test18</option>
<option value="19">test19</option>
<option value="20">test20</option>
</select>
So when user selects "test1" from first select boxm he will see only "test2", "test3" and "test4" on the second select box; "test2" from first will show "test6", "test7" and "test8" in the second box.
How can I use JavaScript to resolve this problem?

If you can use jQuery then you can always just clear and append the options to the second select.
$('#ExtraField_1').change(function(){
$('#ExtraField_2').find('option').remove()
if($(this).val() == '1'){
$('#ExtraField_2').append($("<option </option>").attr('value','2').text('test2'));
$('#ExtraField_2').append($("<option></option>").attr('value','3').text('test3'));
$('#ExtraField_2').append($("<option></option>").attr('value','4').text('test4'));
}
if($(this).val() == '2'){
$('#ExtraField_2').append($("<option></option>").attr('value','5').text('test5'));
$('#ExtraField_2').append($("<option></option>").attr('value','6').text('test6'));
$('#ExtraField_2').append($("<option></option>").attr('value','7').text('test7'));
}
});
​
http://jsfiddle.net/8XVuv/2/
using only javascript is a bit more complicated but I would still take the same approach.
function createOption(otext,oValue){
var newOption = document.createElement('option');
newOption.text = otext;
newOption.value = oValue;
return newOption;
}
function clearSelect(theSelect){
for(var i = 0;i <= theSelect.options.length+1;i++)
{
theSelect.remove();
}
}
function onSelect(theSelect){
var nextSelect = document.getElementById('ExtraField_2');
clearSelect(nextSelect);
var selected = theSelect.options[theSelect.selectedIndex];
if(selected.value == 1){
nextSelect.add(createOption('test2','2'));
nextSelect.add(createOption('test3','3'));
nextSelect.add(createOption('test4','4'));
}
if(selected.value == 2){
nextSelect.add(createOption('test5','5'));
nextSelect.add(createOption('test6','6'));
nextSelect.add(createOption('test7','7'));
}
}
with html:
<select id="ExtraField_1" name="ExtraField_1" onchange="javascript: onSelect(this);" >
<option value="0">Select a test..</option>
<option value="1">test1</option>
<option value="2">test2</option>
<option value="3">test3</option>
<option value="4">test4</option>
<option value="5">test5</option>
<option value="6">test6</option>
<option value="7">test7</option>
<option value="8">test8</option>
<option value="9">test9</option>
<option value="10">test10</option>
<option value="11">test11</option>
<option value="12">test12</option>
</select>
<select id="ExtraField_2" name="ExtraField_2">
<option value="0">Select from the left</option>
</select>​
as you can see it still does what you expect but you are not hiding options.
http://jsfiddle.net/upKzW/13/

$('#ExtraField_1').change(function() {
$('#ExtraField_2').val(this.value);
});
http://jsfiddle.net/judearasu/rF8G6/