Cause analysis and solutions for window.location events not performed when the page is closed _javascript tips

1, the problem description:

JS defines widow.location = function (), the logout () function is not executed when the page closes.

Window.onunload = function () {
    logout ();
  }

function logout (Reqparam, callback) {
    var usermanageserviceurl = "http://" + getserveraddr () + "/axis2/services/" Usermanageservice ";
    var urllist = [];
    var url = window.location.href;
    Urllist = Url.split ("?");
    var SessionID = urllist[1];
    Reqparam.sessionid = SessionID;
    var pl = new Soapclientparameters ();
    var reqparamstr = json.stringify (Reqparam);
    Pl.add ("Reqparam", reqparamstr);
    Soapclient.invoke (Usermanageserviceurl, "logout", pl, False, callback);
  }

2, the problem reason:

The Soapclient.invoke () method is called in logout (), and the argument is true, which means that the front-end and server communicate asynchronously, that is, the front-end has not received a response from the server side, and the following statement has been executed, which is performed as a front-end execution logout ( has not yet waited for the server's response, the page has been closed, so the performance of logout () has not been performed.

3, the solution:

Change the front-end and server communication mode to sync, and the problem is resolved by changing the Soapclient.invoke () method to False.