编辑代码

/*
Name: fnGetEventHandler
Function: main of this function
            1.store the nature onmessage function
            2.return the param by post message to main onmessage
            3.reset the onmessage function
            4.tell the parent msg loop task is complete
Param: null
Return: onmessage.name==fnCallBackMainGetInhouseReservationList
        let objParam = {
                "name": "fnCallbackGetInhouseReservationList",
                "aryObjReservationList": aryObjReservationList
            }
 */
function fnMainGetEventHandler()
{
    window.fnOldOnmessage= window.onmessage;

    window.onmessage= function(objMsg){
        

        console.log(objMsg);
        //alert(objMsg);

        if( objMsg.data.strName.match("fnCallBackGetEventHandler"))
        {
            //alert('fnCallbackGetInhouseReservationList');

            fnResetOnmessage();

            //console.log("a");

           
            objMsg.data.strName= "fnCallBackMainGetEventHandler";
            objMsg.data.bIfContinue= true;

            window.postMessage(objMsg.data);
            
        }
        else
            window.fnOldOnmessage(objMsg);
        
    }

    fnGetEventHandler();
    
}

function fnResetOnmessage( )
{
    window.onmessage = window.fnOldOnmessage;
    window.fnOldOnmessage= null;

}



function fnGetEventHandler()
{
    let xmlhttp= new XMLHttpRequest();
    xmlhttp.onreadystatechange = function () {
        if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
            console.log("fnGetReservationDetails: ");
            console.log(xmlhttp.responseText);
            //objParam.objReservationDetails= rtn.responseJSON.ResScreenData.ResRows;
            //fnTasksLoop("fnGetReservationDetails",xmlhttp.responseText);
            }
            }
    xmlhttp.open("GET","https://app9.rmscloud.cn/api/UtilitiesService/InitEventHandler"+
                        "?placeholder="+  Math.random());
    xmlhttp.setRequestHeader('content-Type','application/json; charset=utf-8');
    xmlhttp.send();
}