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JavaScript Object-Oriented JavaScript Getters and Setters Creating Setter Methods

Posted by Frans Joakim Titulaer
Frans Joakim Titulaer
5,001 Points

There isn't anything in the videocourse so far that shows us how to answer question 2 is there?

Isn't this a jump?

creating_setters.js 
class Student {
    constructor(gpa, credits){
        this.gpa = gpa;
        this.credits = credits;
    }

    stringGPA() {
        return this.gpa.toString();
    }

    set major(_major) {
      if(this.credits > 60){
        this.major = _major
      } else {
        this.major = 'None'
      }
    }

    get level() {
        if (this.credits > 90 ) {
            return 'Senior';
        } else if (this.credits > 60) {
            return 'Junior';
        } else if (this.credits > 30) {
            return 'Sophomore';
        } else {
            return 'Freshman';
        }
    }
}

var student = new Student(3.9, 60);

2 Answers

Frans Joakim Titulaer
Frans Joakim Titulaer
5,001 Points
Frans Joakim Titulaer
Frans Joakim Titulaer
5,001 Points

So it worked when I made the following changes, but I would still like to know whyyy:

set major(major) { if(this.credits > 60){ this._major = major

Jason Larson
Jason Larson
8,361 Points
Jason Larson
Jason Larson
8,361 Points

The video just before the challenge is called "Setters". This topic is covered starting at about one minute into the video. To answer your question, you use the underscore because the name of a property cannot be the same as the name of a getter or setter method. And typically, the underscore is going to be in the this portion of the assignment, like so:

set major(major) {
  if (this.credits > 60) { this._major = major }
  else { this._major = 'None'; }
}