SOURCE

function FORM(){
    return {
        "data":{
            "attend_item_id":902,
            "start_time":"2022-05-24 08:30",
            "end_time":"2022-05-24 18:30"
        }
    }
}

function test(){
    attend_item_id=FORM().data.attend_item_id;
    if (attend_item_id!=902){return}
    var start_time=FORM().data.start_time;
    start_time=start_time.substring(start_time.length-5);
    var end_time=FORM().data.start_time;
    end_time=end_time.substring(end_time.length-5);
    var start_flag="12:00";
    var end_flag="12:30";
    if (start_time<start_flag&&end_flag<end_time){
        console.log("111")
    }
    else{
        console.log("222")
    }
}
test()