我必须计算所选日期之间的工作日总数,并且我使用以下逻辑
this.businessDays = this.calcBusinessDays(this.startDate, this.endDate);
calcBusinessDays(d1: Date, d2: Date) {
let date1 = new Date(d1);
let date2 = new Date(d2);
let oneDay = 1000 * 60 * 60 * 24;
let difference = Math.floor((date2.getTime() - date1.getTime()) / oneDay);
let businessDays = 0;
let i: number;
this.httpService
.getHolidays(moment(date1).format('YYYY-MM-DD'), moment(date2).format('YYYY-MM-DD')) //start-date and end date are a part of query params in YYYY-MM-DD format.
.subscribe((res: HttpResponse<HolidaysListInterface>) => {
this.holidaysList = res.body.holidayDates;
for (i = 0; i < difference; ++i) {
let day = date1.getDay();
let isHoliday = this.holidaysList.indexOf(moment(date1).format('YYYY-MM-DD')) != -1;
if (day != 0 && day != 6 && !isHoliday) {
++businessDays;
}
date1.setDate(date1.getDate() + 1);
}
});
return businessDays;
}
现在,这里的问题是我每次都得到0
作为返回值。该函数甚至在Http调用完成之前就返回该值。有什么解决方法?
答案 0 :(得分:2)
因为这就是异步请求的工作方式。它们是异步执行的,而不管您指定的实际执行顺序。您可以进一步了解here。
一种解决问题的方法是
任何直接依赖于HTTP调用响应的内容应该都应包含在订阅中
或换句话说
在需要回复的地方订阅
要记住的另一件事是,您无法同步返回异步变量(此处为businessDays
。
您还可以使用RxJS map
运算符将响应转换为所需的格式
尝试以下
businessDays: any;
someFunc() {
this.calcBusinessDays(this.startDate, this.endDate).subscribe(
businessDays => this.businessDays = businessDays,
error => {
// always good practice to handle HTTP errors
}
);
}
calcBusinessDays(d1: Date, d2: Date): Observable<any> { // <-- return observable here
let date1 = new Date(d1);
let date2 = new Date(d2);
let oneDay = 1000 * 60 * 60 * 24;
let difference = Math.floor((date2.getTime() - date1.getTime()) / oneDay);
let businessDays = 0;
let i: number;
return this.httpService
.getHolidays(moment(date1).format('YYYY-MM-DD'), moment(date2).format('YYYY-MM-DD')) //start-date and end date are a part of query params in YYYY-MM-DD format.
.pipe(
map((res: HttpResponse<HolidaysListInterface>) => {
this.holidaysList = res.body.holidayDates;
for (i = 0; i < difference; ++i) {
let day = date1.getDay();
let isHoliday = this.holidaysList.indexOf(moment(date1).format('YYYY-MM-DD')) != -1;
if (day != 0 && day != 6 && !isHoliday) {
++businessDays;
}
date1.setDate(date1.getDate() + 1);
}
return businessDays; // <-- return modified value here
})
);
}