当我在Angular应用程序中从一页导航到另一页时，遇到以下错误

Question

  

错误：eventTask'undefined.addEventListener：message'：无法转换为'running'，期望状态为'scheduled'，为'notScheduled'

我仅在IE11中面临此问题，并且在其他浏览器中也能正常工作

    conn = dbConnect(MySQL(),user ="user_id",password = "pwd",dbname ="db_name",host ="localhost")

    a="2018-07-29"
    query <-"delete from table tab_name where date <= "
    dbSendQuery(conn,paste0( query,"'",a,"'"))