[javascript] Is it possible to use JS to open an HTML select to show its option list?

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);
    }

}