1 function Student(name, gender, age, grade, teacher)
 2     {
 3         this.name = name;
 4         this.gender = gender;
 5         this.age = age;
 6         this.grade = grade;
 7         this.teacher = teacher;
 8     }
 9     var bob = new Student("bob", "male", 15, 10, "Marlow");
10     alert(bob.age); //输出15
11     var susan = new Student("susan", "female", 10, 5, "Gresham");
12     alert(susan.gender); //输出 'female' 

1 var bob = new Student("bob", "male", 15, 10, "Marlow");
2     alert(bob.age); //输出15
3     bob.age = 9;
4     alert(bob.age); //输出9; 

1 var bob = new Student("bob", "male", 15, 10, "Marlow");
2 alert(bob.age); //输出15
3 bob.age = -50;
4 alert(bob.age); //输出-50; 

 1 function Student(name, gender, age, grade, teacher)
 2     {
 3         var studentName = name;
 4         var studentGender = gender;
 5         var studentGrade = grade;
 6         var studentTeacher = teacher;
 7         var studentAge = age;
 8         this.getAge = function()
 9         {
10             return studentAge;
11         };
12         this.setAge = function(val)
13         {
14             studentAge = Math.abs(val); //使用绝对值，确保年龄是正值
15         };
16     }
17     var bob = new Student("bob", "male", 15, 10, "Marlow");
18     alert(bob.studentAge); //未定义，因为年龄在类定义中受私有保护
19     alert(bob.getAge()); //输出15
20     bob.setAge(-20);
21     alert(bob.getAge()); //输出20 

 1 function Student(name, gender, age, grade, teacher)
 2 {
 3     var studentName = name;
 4     var studentGender = gender;
 5     var studentGrade = grade;
 6     var studentTeacher = teacher;
 7     var studentAge = age;
 8     this.getName = function()
 9     {
10         return studentName;
11     };
12     this.getGender = function()
13     {
14         return studentGender;
15     };
16     this.getGrade = function()
17     {
18         return studentGrade;
19     };
20     this.getTeacher = function()
21     {
22         return studentTeacher;
23     };
24     this.getAge = function()
25     {
26         return studentAge;
27     };
28     this.setAge = function(val)
29     {
30         studentAge = Math.abs(val); //使用绝对值，确保年龄是正值
31     };
32 }
33 var bob = new Student("bob", "male", 15, 10, "Marlow");
34 alert(bob.studentGender); //未定义，因为性别在类定义中受私有保护
35 alert(bob.getGender()); //输出 'male' 

 1 function Student( properties )
 2     {
 3         var $this = this;  //将类范围存储到名为$this的变量中
 4         //迭代处理对象的属性
 5         for ( var i in properties )
 6         {
 7             (function(i)
 8             {
 9                 // 动态创建访问器方法
10                 $this[ "get" + i ] = function()
11                 {
12                     return properties[i];
13                 };
14             })(i);
15         }
16     }
17     // 创建一个新的用户对象实例，并传递属性的对象
18     var student = new Student(
19     {
20         Name: "Bob",
21         Age: 15,
22         Gender: "male"
23     });
24     alert(student.name); //因属性是私有的而未定义
25     alert(student.getName()); //输出 "Bob"
26     alert(student.getAge()); //输出15
27     alert(student.getGender()); //输出 "male" 

 1 var student = new Student(
 2     {
 3         Name: "Bob",
 4         Age: 15,
 5         Gender: "male"
 6     });
 7     var student = new Student(
 8     {
 9         Age: 15,
10         Name: "Bob",
11         Gender: "male"
12     });
13     var student = new Student(
14     {
15         Gender: "male",
16         Age: 15,
17         Name: "Bob"
18     }); 

 1 function Worker()
 2 {
 3     this.getMethods = function(properties, scope)
 4     {
 5         var $this = scope;  //将类范围存储到名为$this的变量中
 6         //迭代处理对象的属性
 7         for ( var i in properties )
 8         {
 9             (function(i)
10             {
11                 // 动态创建访问器方法
12                 $this[ "get" + i ] = function()
13                 {
14                     return properties[i];
15                 };
16             //动态地创建一个分析整数，并确保是正值的更改器方法。
17             $this[ "set" + i ] = function(val)
18             {
19                 if(isNaN(val))
20                 {
21                     properties[i] = val;
22                 }
23                 else
24                 {
25                     properties[i] = Math.abs(val);
26                 }
27             };
28             })(i);
29         }
30     };
31 }
32 // CommissionWorker "子类"和WageWorker "子类"
33 //继承Worker的属性和方法。
34 CommissionWorker.prototype = new Worker();
35 WageWorker.prototype = new Worker();
36 function CommissionWorker(properties)
37 {
38     this.getMethods(properties, this);
39     //计算收入
40     this.getIncome = function()
41     {
42         return properties.Sales * properties.Commission;
43     }
44 }
45 //要求有下列属性：薪水、每周小时数、每年周数
46 function WageWorker(properties)
47 {
48     this.getMethods(properties, this);
49     //计算收入
50     this.getIncome = function()
51     {
52         return properties.Wage * properties.HoursPerWeek * properties.WeeksPerYear;
53     }
54 }
55 var worker = new WageWorker(
56 {
57     Name: "Bob",
58     Wage: 10,
59     HoursPerWeek: 40,
60     WeeksPerYear: 48
61 });
62 alert(worker.wage); //未定义。薪水是私有属性。
63 worker.setWage(20);
64 alert(worker.getName());   //输出 "Bob"
65 alert(worker.getIncome()); //输出 38,400 (20*40*48)
66 var worker2 = new CommissionWorker(
67 {
68     Name: "Sue",
69     Commission: .2,
70     Sales: 40000
71 });
72 alert(worker2.getName());   //输出 "Sue"
73 alert(worker2.getIncome()); //输出8000（2% 乘40,000） 

1 CommissionWorker.prototype = new Worker();
2 WageWorker.prototype = new Worker(); 

 1 var car = "Toyota";
 2     if(car == "Toyota")
 3     {
 4         car = "Toyota - We never stop...and you won't either.";
 5     }
 6     alert(car); //输出Toyota——我们从未停上，你也如此。
 7     car = "Toyota"; //将汽车设回成原始值。
 8     function makeFord(car)
 9     {
10         car = "Ford";
11     }
12     makeFord(car);
13     alert(car); //输出"Toyota"，因为汽车在函数范围中已改动。 

1 var car = new Object();
2     car.brand = "Toyota"
3     function makeFord(car)
4     {
5         car.brand = "Ford";
6     }
7     makeFord(car);
8     alert(car.brand); //输出“Ford”