我在学习dropzone代码片段时遇到了emit函数。

<?php
        if(isset($update) && !empty($team_marketing_photos)){
    ?>
        var team_marketings = '<?php echo json_encode($team_marketing_photos,JSON_FORCE_OBJECT) ?>';
        team_marketings = JSON.parse(team_marketings)
    <?php }else{
        ?>
        var team_marketings = "";
        <?php
    } ?>

    let dz1 = $(".js-marketing-dropzone").dropzone({
        ...dropzoneOptions,

        init: function () {
            if ( team_marketings != '') {
                var _this = this
                $.each(team_marketings, function(key,value){
                    var teamMarketingCounter = 'team_marketing' + key
                    if ($(_this.element).attr('id') == teamMarketingCounter) {

                        var mockFile3 = {
                            name: value.photo_name,
                            size: 12345
                        }
                        _this.emit("addedfile", mockFile3)
                        _this.emit("complete", mockFile3)
                        _this.emit("thumbnail", mockFile3, value.photo_name)

                        $(_this.element).find('input:hidden').val(value.id);
                    }
                })
            }
        },
    });

.emit函数是做什么的？这是某种触发吗？