JQuery select label operation code segment_jquery

//1. Get the selected option value
$('#selectList').val();
//2. Get the text of the selected option
$('#selectList :selected').text( );
//3. Get multiple selected option values ​​and texts
var foo = [];
$('#multiple :selected').each(function(i, selected) {
foo[i] = $(selected).text();
});
// to get the selected values, just use .val() - this returns a string or array
foo = $('#multiple :selected').val();
//4. Use the conditional expression of option option
switch ($('#selectList :selected').text()) {
case 'First Option':
//do something
break;
case 'Something Else':
// do something else
break;
}
// 5. Delete an option with value=2
$("#selectList option[value='2']").remove();
//6. Move the option from list A to list B.
// here we have 2 select lists and 2 buttons. If you click the “add” button,
// we remove the selected option from select1 and add that same option to select2.
// The “ remove” button just does things the opposite way around.
// Thanks to jQuery's chaining capabilities, what was once a rather tricky undertaking with JS can now be done in 6 lines of code.
$().ready( function() {
$('#add').click(function() {
return !$('#select1 option:selected').appendTo('#select2');
}) ;
$('#remove').click(function() {
return !$('#select2 option:selected').appendTo('#select1');
});
});