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Start your free trialHanwen Zhang
20,084 PointsI don't quite understand what does 'String(this.gpa)' works here?
Also, why we don't need to add constructor(gpa, this.gpa)?
class Student {
constructor(gpa){
this.gpa = gpa;
}
stringGPA() {
return String(this.gpa);
}
}
const student = new Student(3.9);
1 Answer
Peter Vann
36,427 PointsHi Hanwen!
this.gpa = gpa;
Just makes the value passed to the class constructor a class/instance attribute/property and as such whenever you need to access it within the class instance you need to reference it with this.gpa.
"this" being that particular class instance.
The String() function just casts/converts the numeric value to a string.
More info:
https://www.w3schools.com/js/js_classes.asp
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/this
I hope that helps.
Stay safe and happy coding!
Hanwen Zhang
20,084 PointsHanwen Zhang
20,084 PointsGot it! Thank you, Peter