select2 dropdown in jquery code example

Example 1: jquery to set value in select2 dropdown button

$("#u20_cre").select2().val(["1","6"]).trigger("change");

Example 2: jquery select2 multiple select all

$("#checkbox").click(function(){
    if($("#checkbox").is(':checked') ){
        $("select > option").prop("selected","selected");
    }else{
        $("select > option").removeAttr("selected");
     }
});

Example 3: select 2 dropdown

$('#element').select2({
    placeholder: 'Select a option',
    minimumInputLength: 3,
    ajax: {
        url: route('api.fetch-options'),
        dataType: 'json',
        type: 'GET',
        quietMillis: 50,
        data: function (params) {
            return {
                visitor_name: params.term
            }
        },
        processResults({ data }) {
            return {
                results: $.map(data, function (item) {
                    return {
                        text: item.name,
                        id: item.id,
                    }
                })
            }
        }
    }
}).change(() => {
	// perform some action on change
});