bootstrap Add alert on the pop-up layer and cancel it after opening the modal. After opening the modal a second time and triggering the alert event, it will alert twice!

$("#" + data[i].id).on('click', function () {
                    var that = this;
                    $("#uploadmodal").modal('show');
                    $("#submit").on('click', function () {
                        var val = $('#sykmmc option:selected').text();
                        var opV = $('#sykmmc option:selected').val()
                        if(opV=="10086"){
                            alert('您还未选择科目!');
                            return false;
                        }
                        $(that).parent().find("span").text(val)
                        if($(that).text()=="匹配"){
                            $(that).text("修改")
                        }
                        if($(that).parent().parent().find("td").eq(4).text()=="未匹配")             {
                            $(that).parent().parent().find("td").eq(4).text("已匹配")
                        }
                        $("#uploadmodal").modal('hide');
                    })
                }

Every time the modal is canceled and the modal is triggered again after it is opened again, there will be one more alert than before.