JSFiddle - React, Tailwind, and code Playground

HTML

<select name="foo">
    <option value="alpha">alpha</option>
</select>

JavaScript

console.log('go');

function check_add(select_name, value) {
    if ($("SELECT[name=" + select_name + "] option[value=" + value + "]").length == 0) { 
        $("SELECT[name=" + select_name + "]").append($("<option />").text(value || '').val(value || ''));
    }

try
{
    
check_add('foo', "D:\Results\BDS2007\EXE\TestEntityTransport.exe");
    
} catch (E)
{
    console.log(E.Message);
}

   /*
    
function appendOption( parent, val ) {

    var $select = $('select[name="' + parent + '"]'), 
        $options = $select.children('[value="' + val + '"]');
    
    if ( !$options.length ) {
        $("<option/>", {
            value: val, 
            text: val
        }).appendTo( 'select[name="' + parent + '"]' );
    }
}


var options = [ "D:\Results\BDS2007\EXE\TestEntityTransport.exe", "beta", "gamma", "gamma", "beta" ];

$.each( options, function( idx, opt ) {
   appendOption("foo", opt);
});

*/
// Assertions

console.log( 
    $('select[name="foo"]').children().length === 3 && 
    "Pass: There are 3 options" || "Fail"
);