关闭页面window.location事件未执行的原因及解决方法

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);
}