TypeError customclass.method不是函数

Question

我有一个自定义的Javascript类Workout，它有一个复制自己的自定义方法。

当我在getCalArray函数中使用copyWorkout方法作为循环的一部分来遍历一个Workout数组时，我可以让该函数通过测试，但当我在另一个函数中使用该函数时，我会得到一个TypeError-copyWorkut不是函数；

有什么想法吗？Javascript解释器似乎再也找不到类/类型了，但我不知道如何解决这个问题。

let Workout = class {
constructor(workoutNumber, weekNum = Math.ceil(workoutNumber/7),
title = 'Rest Day', description = '', workoutDate = null) {
this.workoutNum = workoutNumber;
this.weekNum = weekNum;
this.title = title;
this.description = description;
this.workoutDate = workoutDate;

}
addDate(inputDate) {
this.workoutDate = inputDate;
}
toString() {
return `Workout Num: ${this.workoutNum}, Week Num: ${this.weekNum}, 
title: ${this.title}, description: ${this.description}, Workout Date: ${this.workoutDate},`
}
copyWorkout = () =>  {
return new Workout(this.workoutNum, this.weekNum, this.title, this.description, this.workoutDate);
}
}
function getDateDaysFrom(numDays, inputDate) {
let outputDate = new Date(inputDate.getTime());
outputDate.setDate(outputDate.getDate() + numDays);
return outputDate;
}
const dateFromString = (inputDate) => {
const dateArr = inputDate.split('-');
const m = dateArr[0];
const d = dateArr[1];
const y = dateArr[2];
return new Date(y, m-1, d, 0, 0, 0, 0);
};
const getStartDate = (numDaysOfWorkoutSchedule, raceDate) => {
let startDate = getDateDaysFrom(-numDaysOfWorkoutSchedule, dateFromString(raceDate));
while (startDate.getDay() !== 0) {
startDate = getDateDaysFrom(-1, startDate);
}
return startDate;
};
const getCalArray = (startDateStr, workoutSchArr) => {
let i;
let daysAvailable;
let currentWeek;
let lastWeekNum = 0;
let calendarArray = [];
let calWeekArray = [];
let startDate = getStartDate(0, startDateStr);
for (i=0; i<workoutSchArr.length; i++) {
currentWeek = workoutSchArr[i].weekNum;
if (currentWeek !== lastWeekNum) {
//for each day if true, then available.  if false, then booked
daysAvailable = [true, true, true, true, true, true, true];
if (lastWeekNum > 0) {
calendarArray.push(calWeekArray) ;
calWeekArray = [];
}
}
let newDate;
//find first available day and set date based on day and weeknum
if (daysAvailable[0]) {
newDate = getDateDaysFrom((currentWeek-1)*7, startDate)
daysAvailable[0] = false;
} else if (daysAvailable[1]) {
newDate = getDateDaysFrom((currentWeek-1)*7+1, startDate)
daysAvailable[1] = false;
} else if (daysAvailable[2]) {
newDate = getDateDaysFrom((currentWeek-1)*7+2, startDate)
daysAvailable[2] = false;
} else if (daysAvailable[3]) {
newDate = getDateDaysFrom((currentWeek-1)*7+3, startDate)
daysAvailable[3] = false;
} else if (daysAvailable[4]) {
newDate = getDateDaysFrom((currentWeek-1)*7+4, startDate)
daysAvailable[4] = false;
} else if (daysAvailable[5]) {
newDate = getDateDaysFrom((currentWeek-1)*7+5, startDate)
daysAvailable[5] = false;
} else if (daysAvailable[6]) {
newDate = getDateDaysFrom((currentWeek-1)*7+6, startDate)
daysAvailable[6] = false;
}
let newWorkout = workoutSchArr[i].copyWorkout();
newWorkout.addDate(newDate);
calWeekArray.push(newWorkout);
lastWeekNum = currentWeek;
}
calendarArray.push(calWeekArray);
return calendarArray;
};
let printWorkoutSchedule = (workoutSchedule) => {
let outputString = "";
let i;
for (i=0; i<workoutSchedule.length; i++) {
const workout = workoutSchedule[i];
const workoutString = `Workout ${workout.workoutNum} - 
Week ${workout.weekNum} - ${workout.title} ${workout.description}`;
outputString += workoutString + 'n';
}
return outputString;
};
let inputArray = [new Workout(1, 1, 'SWIM:',
'600yds 4 x 50yds, 4 x 100yds'), new Workout(2, 1, 'BIKE:',
'45 minutes'), new Workout(3, 1, 'RUN:',
'15 minutes'), new Workout(4, 2, 'SWIM:',
'700yds 6 x 50yds, 4 x 100yds'), new Workout(5, 2, 'BIKE:',
'45 minutes'), new Workout(6, 2, 'RUN:',
'20 minutes'), ];
let startDate = '09-01-2020';
let calArrayExample = getCalArray(startDate, inputArray)
console.log(printWorkoutSchedule(calArrayExample));

Answer 1

所以我找到了一个解决方案，我没有使用类方法进行复制，而是使用这个方法进行复制-如何克隆javascript ES6类实例

因此，不要复制Workout((。。。我现在使用Object.assign(Object.create(Object.getPrototypeOf(WorkoutArr[I]((，WorkoutArr[I](来创建Workout的复制实例。

似乎解决了我以前的所有问题，但我仍然很好奇如何在不使用Typescript的情况下获得更多的类型稳定性。