Question

我想在Javascript中实现has-a关系，这里有Department对象，Department有多个学生，因此在Department中引用了一系列Student对象，

这是代码，

(function(){
     alert(" Hi !!!!! ");

    var engBranch = {
        compEng : "Bachelor of Engineering in Computer Science",
        mechEng : "Bachelor of Engineering in Mechanical",
        cvlEng  : "Bachelor of Engineering in Civil",
        prodEng : "Bachelor of Engineering in Production",
        elecEng : "Bachelor of Engineering in Electrical",
        extcEng : "Bachelor of Engineering in Electronics and Telecomminication"
    };



    var StudentIdGenerator = function(studentId,dept){
        var _studentId = "";

        if(dept == engBranch.compEng){
            _studentId = "CS"+studentId;
        }else if(dept == engBranch.mechEng){
            _studentId = "M"+studentId;
        }else if(dept == engBranch.cvlEng){
            _studentId = "CVL"+studentId;
        }else if(dept == engBranch.prodEng){
            _studentId = "P"+studentId;
        }else if(dept == engBranch.elecEng){
            _studentId = "ELC"+studentId;
        }else if(dept == engBranch.extcEng){
            _studentId = "EXTC"+studentId;
        }

        return _studentId;
    }

    var Student = function(studentName,studentId,department){

        var _studentId = StudentIdGenerator(studentId,department);

        return function(){
            this.getStudentName = function(){
                return studentName;
            } 

            this.getStudentId = function (){
                return _studentId;
            }

            this.display = function(){
                return "The Student Name is "+this.getStudentName()+" having ID "+this.getStudentId();
            }
        };
    }

    Student.prototype.display = function(){
        return "The Student Name is "+this.getStudentName()+" having ID "+this.getStudentId();
    }

    var Department = function(deptName,deptId){     

        this.getDeptName = function(){
            return deptName;
        }

        this.getDeptId = function(){
            return deptId;
        }

        this.setStudents = function(students){
            this.students = students;
        }

        this.getStudents = function(){
            return this.students;
        }
    }

    Department.prototype.display = function(){
        var str = "This is department, "+this.getDeptName()+", Students Belonging to this department are \n";

        for(var x=0; x < this.getStudents().length;x++){
            str += this.getStudents()[x].display()+"\n";
        }

        return str;
    }


    var department = new Department(engBranch.cvlEng,"CMP007");

    var studentArray = [ 
                            new (Student("Jack Nicholson","0021",department.getDeptName()))(),
                            new (Student("Heidi Klum","0043",department.getDeptName()))(),
                            new (Student("Stephen Halkwins","0345",department.getDeptName()))(),
                            new (Student("Jay Leno","1045",department.getDeptName()))(),
                            new (Student("Tomy Lee Johnes","3475",department.getDeptName()))(),
                            new (Student("Oliver Jackson","7345",department.getDeptName()))()
                        ];

    department.setStudents(studentArray);

    alert(department.display());

   })();

在上面的代码中，对象“engBranch”包含工程课程中可用的所有流。

有一个单独的函数StudentIdGenerator（），其职责是根据学生所属的部门创建一个StudentId。

Student Constuctor函数本身返回一个新函数，请看看Student函数返回的内容。

学生的原型显示功能完全没有要求，请忽略它，

部门构造函数，

在Department原型链中显示功能，

所以，我的问题是，我的例子是一个适当的 - 一对多关系的实现。

我可以对以下代码执行新的或额外的操作。

等待你的回复

在Javascript中实现has-a关系

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