How to fix ‘Cannot read property 'forEach' of undefined’ error in Angular
0
I have a bug, but I don't know what else to do to fix it. Below is my code and the error:
courses: any = ;
ngOnInit() {
this.locale = this.localeService.currentLocale();
this.user = this.authService.getCurrentUser();
this.userService.getCoursesInProgress(this.user.id).subscribe(courses => {
this.coursesInProgress = ;
courses.forEach(n => {
const courseObj: Course = new Course(n);
this.coursesInProgress.push(courseObj);
});
});
this.userService.getCoursesFinished(this.user.id).subscribe(courses => {
this.coursesFinished = ;
courses.forEach(n => {
const courseObj: Course = new Course(n);
this.coursesFinished.push(courseObj);
});
});
}
TypeError · Cannot read property 'forEach' of undefined
angular typescript angular7 edited Jan 2 at 11:04
veben
2,16041329
asked Jan 2 at 10:35
Alexandre MisaiphonAlexandre Misaiphon
1
|
show 6 more comments
0
I have a bug, but I don't know what else to do to fix it. Below is my code and the error:
courses: any = ;
ngOnInit() {
this.locale = this.localeService.currentLocale();
this.user = this.authService.getCurrentUser();
this.userService.getCoursesInProgress(this.user.id).subscribe(courses => {
this.coursesInProgress = ;
courses.forEach(n => {
const courseObj: Course = new Course(n);
this.coursesInProgress.push(courseObj);
});
});
this.userService.getCoursesFinished(this.user.id).subscribe(courses => {
this.coursesFinished = ;
courses.forEach(n => {
const courseObj: Course = new Course(n);
this.coursesFinished.push(courseObj);
});
});
}
TypeError · Cannot read property 'forEach' of undefined
angular typescript angular7 edited Jan 2 at 11:04
veben
2,16041329
asked Jan 2 at 10:35
Alexandre MisaiphonAlexandre Misaiphon
1
is the courses array defined? It doesn't look like its defined.
– digital-pollution
Jan 2 at 10:38
3
The API is returningcoursesasundefinedornull. Please see the browser's network tab to check what its returning. Alternatively, you can useconsole.log(courses)to see whats returned.
– Faisal
Jan 2 at 10:39
Sidenote, you could writethis.coursesInProgress = courses.map(n => new Course(n))
– Jeremy Thille
Jan 2 at 10:42
1
The error tells you that you're trying to useforEachonundefined(and contains the line number where the problem is). Your code usesforEachoncourses. So that means thatcoursesis undefined.coursesis the event emitted by the observable returned by one of your service method calls (the line number indicates which one it is). So that means that the service doesn't return an observable emitting an array of courses as you think, but instead emitsundefined. You haven't posted the service, so we can't help more.
– JB Nizet
Jan 2 at 10:42
1
See this:stackoverflow.com/questions/43724426/…
– i_th
Jan 2 at 10:46
|
show 6 more comments
0
0
0
0
I have a bug, but I don't know what else to do to fix it. Below is my code and the error:
courses: any = ;
ngOnInit() {
this.locale = this.localeService.currentLocale();
this.user = this.authService.getCurrentUser();
this.userService.getCoursesInProgress(this.user.id).subscribe(courses => {
this.coursesInProgress = ;
courses.forEach(n => {
const courseObj: Course = new Course(n);
this.coursesInProgress.push(courseObj);
});
});
this.userService.getCoursesFinished(this.user.id).subscribe(courses => {
this.coursesFinished = ;
courses.forEach(n => {
const courseObj: Course = new Course(n);
this.coursesFinished.push(courseObj);
});
});
}
TypeError · Cannot read property 'forEach' of undefined
angular typescript angular7 edited Jan 2 at 11:04
veben
2,16041329
asked Jan 2 at 10:35
Alexandre MisaiphonAlexandre Misaiphon
1
I have a bug, but I don't know what else to do to fix it. Below is my code and the error:
courses: any = ;
ngOnInit() {
this.locale = this.localeService.currentLocale();
this.user = this.authService.getCurrentUser();
this.userService.getCoursesInProgress(this.user.id).subscribe(courses => {
this.coursesInProgress = ;
courses.forEach(n => {
const courseObj: Course = new Course(n);
this.coursesInProgress.push(courseObj);
});
});
this.userService.getCoursesFinished(this.user.id).subscribe(courses => {
this.coursesFinished = ;
courses.forEach(n => {
const courseObj: Course = new Course(n);
this.coursesFinished.push(courseObj);
});
});
}
TypeError · Cannot read property 'forEach' of undefined
angular typescript angular7 angular typescript angular7 edited Jan 2 at 11:04
veben
2,16041329
asked Jan 2 at 10:35
Alexandre MisaiphonAlexandre Misaiphon
1
edited Jan 2 at 11:04
veben
2,16041329
asked Jan 2 at 10:35
Alexandre MisaiphonAlexandre Misaiphon
1
edited Jan 2 at 11:04
veben
2,16041329
edited Jan 2 at 11:04
veben
2,16041329
edited Jan 2 at 11:04
veben
2,16041329
2,16041329
asked Jan 2 at 10:35
Alexandre MisaiphonAlexandre Misaiphon
1
asked Jan 2 at 10:35
Alexandre MisaiphonAlexandre Misaiphon
1
asked Jan 2 at 10:35
Alexandre MisaiphonAlexandre Misaiphon
1
1
is the courses array defined? It doesn't look like its defined.
– digital-pollution
Jan 2 at 10:38
3
The API is returningcoursesasundefinedornull. Please see the browser's network tab to check what its returning. Alternatively, you can useconsole.log(courses)to see whats returned.
– Faisal
Jan 2 at 10:39
Sidenote, you could writethis.coursesInProgress = courses.map(n => new Course(n))
– Jeremy Thille
Jan 2 at 10:42
1
The error tells you that you're trying to useforEachonundefined(and contains the line number where the problem is). Your code usesforEachoncourses. So that means thatcoursesis undefined.coursesis the event emitted by the observable returned by one of your service method calls (the line number indicates which one it is). So that means that the service doesn't return an observable emitting an array of courses as you think, but instead emitsundefined. You haven't posted the service, so we can't help more.
– JB Nizet
Jan 2 at 10:42
1
See this:stackoverflow.com/questions/43724426/…
– i_th
Jan 2 at 10:46
|
show 6 more comments
is the courses array defined? It doesn't look like its defined.
– digital-pollution
Jan 2 at 10:38
3
The API is returningcoursesasundefinedornull. Please see the browser's network tab to check what its returning. Alternatively, you can useconsole.log(courses)to see whats returned.
– Faisal
Jan 2 at 10:39
Sidenote, you could writethis.coursesInProgress = courses.map(n => new Course(n))
– Jeremy Thille
Jan 2 at 10:42
1
The error tells you that you're trying to useforEachonundefined(and contains the line number where the problem is). Your code usesforEachoncourses. So that means thatcoursesis undefined.coursesis the event emitted by the observable returned by one of your service method calls (the line number indicates which one it is). So that means that the service doesn't return an observable emitting an array of courses as you think, but instead emitsundefined. You haven't posted the service, so we can't help more.
– JB Nizet
Jan 2 at 10:42
1
See this:stackoverflow.com/questions/43724426/…
– i_th
Jan 2 at 10:46
is the courses array defined? It doesn't look like its defined.
– digital-pollution
Jan 2 at 10:38
is the courses array defined? It doesn't look like its defined.
– digital-pollution
Jan 2 at 10:38
3
3
The API is returning
courses as undefined or null. Please see the browser's network tab to check what its returning. Alternatively, you can use console.log(courses) to see whats returned.– Faisal
Jan 2 at 10:39
The API is returning
courses as undefined or null. Please see the browser's network tab to check what its returning. Alternatively, you can use console.log(courses) to see whats returned.– Faisal
Jan 2 at 10:39
Sidenote, you could write
this.coursesInProgress = courses.map(n => new Course(n))– Jeremy Thille
Jan 2 at 10:42
Sidenote, you could write
this.coursesInProgress = courses.map(n => new Course(n))– Jeremy Thille
Jan 2 at 10:42
1
1
The error tells you that you're trying to use
forEach on undefined (and contains the line number where the problem is). Your code uses forEachon courses. So that means that courses is undefined. courses is the event emitted by the observable returned by one of your service method calls (the line number indicates which one it is). So that means that the service doesn't return an observable emitting an array of courses as you think, but instead emits undefined. You haven't posted the service, so we can't help more.– JB Nizet
Jan 2 at 10:42
The error tells you that you're trying to use
forEach on undefined (and contains the line number where the problem is). Your code uses forEachon courses. So that means that courses is undefined. courses is the event emitted by the observable returned by one of your service method calls (the line number indicates which one it is). So that means that the service doesn't return an observable emitting an array of courses as you think, but instead emits undefined. You haven't posted the service, so we can't help more.– JB Nizet
Jan 2 at 10:42
1
1
See this:stackoverflow.com/questions/43724426/…
– i_th
Jan 2 at 10:46
See this:stackoverflow.com/questions/43724426/…
– i_th
Jan 2 at 10:46
|
show 6 more comments
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is the courses array defined? It doesn't look like its defined.
– digital-pollution
Jan 2 at 10:38
3
The API is returning
coursesasundefinedornull. Please see the browser's network tab to check what its returning. Alternatively, you can useconsole.log(courses)to see whats returned.– Faisal
Jan 2 at 10:39
Sidenote, you could write
this.coursesInProgress = courses.map(n => new Course(n))– Jeremy Thille
Jan 2 at 10:42
1
The error tells you that you're trying to use
forEachonundefined(and contains the line number where the problem is). Your code usesforEachoncourses. So that means thatcoursesis undefined.coursesis the event emitted by the observable returned by one of your service method calls (the line number indicates which one it is). So that means that the service doesn't return an observable emitting an array of courses as you think, but instead emitsundefined. You haven't posted the service, so we can't help more.– JB Nizet
Jan 2 at 10:42
1
See this:stackoverflow.com/questions/43724426/…
– i_th
Jan 2 at 10:46