Ajax jQuery延迟了早期解析
我正在努力让jQuery延迟为我工作 我试图将许多函数调用链接在一起,这些函数调用使用jQueryAjax jQuery延迟了早期解析,ajax,jquery-deferred,Ajax,Jquery Deferred,我正在努力让jQuery延迟为我工作 我试图将许多函数调用链接在一起,这些函数调用使用jQuery进行$.ajax调用。然后使用下面列出的模式执行语句,但是每个函数都会在ajax调用解决之前返回(因此链将继续) // earlier code runs fine to here }) .then(function (r) { getCurrentYearAbsenceRequestData(); // calls function which contains a $.ajax requ
进行$.ajax
调用。然后使用下面列出的模式执行语句,但是每个函数都会在ajax调用解决之前返回(因此链将继续)
// earlier code runs fine to here
})
.then(function (r) {
getCurrentYearAbsenceRequestData(); // calls function which contains a $.ajax request
})
.then(function (r) {
restructureCurrentYearAbsenceData();
});
// further processing of results
上面调用的函数遵循以下模式:
function getCurrentYearAbsenceRequestData() {
var dfd = $.Deferred();
var today = moment();
var startOfCurrentHolidayYear = moment($clnt.holidayYearStartDate, "DD MMMM").format("DD/MM/YYYY");
var startDayOfCurrentHolidayYear = moment().dayOfYear(startOfCurrentHolidayYear)
var currentDayOfYear = moment().dayOfYear();
if (moment(today).isBefore(startOfCurrentHolidayYear)) { //checks if holiday year started last year
startOfCurrentHolidayYear = moment(startOfCurrentHolidayYear).subtract(1, "years"); //if so subtract 1 year from start of currently holiday year date
};
console.log("Start of Holiday year is " + startOfCurrentHolidayYear);
var getOrgDataQuery = $apiUrl + "/web/lists/getbytitle('AbsenceRequests')/Items?$select=Id,AssocBranch/Title,DateFrom,DateTo,EmployeeLookup/EmployeeName,EmployeeLookup/Id,AbsenceType/AbsenceTypeShort,ReviewOutcome,TotalDays,AbsenceNotes&$expand=AssocBranch/Title,EmployeeLookup/EmployeeName,AbsenceType/AbsenceTypeShort&$filter=DateFrom ge '" + startOfCurrentHolidayYear + "'";
$.ajax(_cnxRest.getRequest(getOrgDataQuery)) //calls personal library function which formats the parameter - this works OK)
.done(function (r) {
console.log("Get Org data success" + r);
var $absDataCurrentYearData = r.d.results;
$absData.allCurrentYear = $absDataCurrentYearData;
dfd.resolve();
})
.fail(function (err) {
logError(err);
});
};
return dfd.promise();
};
我希望$.ajax调用在后续的.then函数运行之前得到解决,并希望收到一些关于我的错误所在的智能建议。异步函数必须返回一个承诺,以便通知其调用方异步性。否则调用方的.then(…).then(…)
链将继续,而不考虑异步性,这是问题中描述的症状
您只是缺少了一些返回,尽管代码也可以进行一些整理
// earlier code runs fine to here
.then(function (r) {
return getCurrentYearAbsenceRequestData();
// ^^^^^^
})
.then(function (r) {
return restructureCurrentYearAbsenceData();
// ^^^^^^
})
.fail(function (err) {
logError(err); // by logging here you will see reported errors arising from the entire chain.
});
function getCurrentYearAbsenceRequestData() {
var startOfCurrentHolidayYear = moment($clnt.holidayYearStartDate, "DD MMMM").format("DD/MM/YYYY");
if(moment(moment()).isBefore(startOfCurrentHolidayYear)) {
startOfCurrentHolidayYear = moment(startOfCurrentHolidayYear).subtract(1, "years");
};
var getOrgDataQuery = $apiUrl + "/web/lists/getbytitle('AbsenceRequests')/Items?$select=Id,AssocBranch/Title,DateFrom,DateTo,EmployeeLookup/EmployeeName,EmployeeLookup/Id,AbsenceType/AbsenceTypeShort,ReviewOutcome,TotalDays,AbsenceNotes&$expand=AssocBranch/Title,EmployeeLookup/EmployeeName,AbsenceType/AbsenceTypeShort&$filter=DateFrom ge '" + startOfCurrentHolidayYear + "'";
return $.ajax(_cnxRest.getRequest(getOrgDataQuery))
// ^^^^^^
.then(function(r) {
$absData.allCurrentYear = r.d.results;
retrun r; // make the result available to the next step in the caller's .then chain, even if it's not going to be used
// ^^^^^^
});
};
主链可简化为:
.then(getCurrentYearAbsenceRequestData) // calls function which contains a $.ajax request
.then(restructureCurrentYearAbsenceData)
.fail(function(err) {
logError(err);
});
这里,retrun是在命名函数中编写的