function Student(sn,sname){
Student.school;
Student.location;
this.sn=sn;
this.sname=sname;
}
Student.school="xx大学";
Student.location="xx市xx路";
s1=new Student("222222222","jhgfds");
document.writeln("Student对象的属性为：
");
for(var i in Student){
document.writeln("student的属性："+i+"="+Student[i]+"
");
}
for(var i in s1){
document.writeln("s1的属性："+i+"="+s1[i]+"
");
}
Student.prototype.display=function Student(){
document.writeln("学生s1的学号："+Student.sn+"姓名"+Student.sname+"
学校："+Student.school+"地址："+Student.location);
}
s1.display();
结果为什么都是未定义啊
