Visual FoxPro数据库程序设计
单选题创建一个名为student的新类，保存新类的类库名称是mylib，新类的父类是Person，正确的命令是（ ）。A CREATE CLASS mylib OF student As PersonB CREATE CLASS student OF Person As mylibC CREATE CLASS student OF mylib As PersonD CREATE CLASS Person OF mylib As student
题目
CREATE CLASS mylib OF student As Person
CREATE CLASS student OF Person As mylib
CREATE CLASS student OF mylib As Person
CREATE CLASS Person OF mylib As student
相似问题和答案
第1题：
下列代码段声明了3个类：class Person()；class Student：public Person{};class Undergraduate：Student{}；下列关于这些类之间关系的描述中，错误的是( )。
A．类Person是类Undergraduate的基类
B．类Undergraduate从类Student公有继承
C．类Student是类Person的派生类
D．类Undergraduate是类Person的派生类
解析：类Undergraduate从类Student私有继承，继承方式缺省则默认是Private。
第2题：
下列程序运行后的输出结果是( )。#include#includeusing namespace std;class Person{public:Person(string n):name(n) { cout<<'P'; }private:string name;};class Date{public:Date(int y=2012,int m=12,int d=21):year(y),month(m),day(d) { cout<<'D'; }
private:int year,month,day;};class Student:public Person{public:Student(string n,int y,int m,int d,char c):birthday(y,m,d),sex(c),Person(n) { cout<<'S'; }private:Date birthday;char sex;};int main(){Student stu1("Zhang",1990,10,1,'F');return 0}
A. S
B.PS
C.DPS
D.PDS
第3题：
已建立一个名为teacher的类，保存该类的类库名称是mylib，则删除该类正确的命令是（ ）。
A)REMOVE CLASS mylib OF teacher
B)REMOVE CLASS teacher OF mylib
C)DELETE CLASS mylib OF teacher
D)DELETE CLASS teacher OF rnylib
第4题：
创建一个名为student的新类，保存新类的类库名称是mylib，新类的父类名是Person，正确的命令是（ ）。
A.CREATE CLASS mylib OF student AS Pcrson
B.CREATE CLASS student OF Person AS mylib
C.CREATE CLASS student OF mylib AS Person
D.CREATE CLASS Person OF mylib AS student
C。【解析】格式为CREATECLASS新类名OF类库名称AS父类名。
第5题：
创建一个名为myteacher的新类，保存新类的类库名称是mylib，新类的父类是Teacher，正确的命令是 （ ）。
A. CREATE CLASS mylib OF myteacher AS Teacher
B. CREATE CLASS myteacher OF Teacher AS mylib
C. CREATE CLASS myteacher OF mylib AS Teacher
D. CREATE CLASS Teacher OF mylib AS myteacher
建立类语句的格式为“CREATE CLASS类名0F类库名AS父类”，题中要求新类的类库名称是mylib，父类是Teacher，因此，正确的命令是“CREATE CLASS myteach- cr OF mylib AS Teacher”。
第6题：
A developer is creating a class Book that needs to access class Paper.The Paper class is deployed in a JARnamedmyLib.jar.Whichthree，taken independently，will allow the developer to use the Paper class while compiling the Book class？（）
A.The JAR fileis located at$JAVA_HOME/jre/classes/myLib.jar.
B.The JAR fileis located at$JAVA_HOME/jre/lib/ext/myLib.jar.
C.TheJ AR fileis located at/foo/myLib.jar and aclasspath environment variable is set that includes /foo/myLib.jar/Paper.class.
D.The JAR fileis located at/foo/myLib.jar and a classpath environment variable is set that includes/foo/myLib.jar.
E.The JAR file is located at/foo/myLib.jar and the Book class is compiled using javac-cp/foo/myLib.jar/Paper Book.java.
F.The JAR file is located at/foo/myLib.jar and the Book class is compiled using javac-classpath/foo/myLib.jar Book.java.
第7题：
创建一个名为student的新类，保存新类的类库名称是mylib，新类的父类是Person，正确的命令是
A．CREATE CLASS mylib OF student As Pemon
B．CREATE CLASS student OF Pe~on As mylib
C．CREATE CLASS student 0F mylib As Pe~on
D．CREATE CLASS Person OF mylib As student
解析：建立类语句的格式为“CREATE CLASS类名OF类库名As父类”，题中要求新类的类库名称是mylib，父类是Person，因此，正确的命令是“CREATE CLASS student OF mylib As Person'’。
第8题：
（ 30 ）下列代码声明了 3 个类
class Person{};
class Student:public Person{};
class Undergraduate:Student{};
下列关于这些类之间关系的描述中，错误的是
A ）类 Person 是类 Undergraduate 的基类
B ）类 Undergraduate 从类 Student 公有继承
C ）类 Student 是类 Person 的派生类
D ）类 Undergraduate 是类 Person 的派生类
第9题：
●以下的SQL 99语句，Student与Person之间的关系是 (62) 。
CREATE TYPE Person(
name char(20)，
address varchar(50))；
CREATE TYPE Student(
under Person
(degree char(20)
department char(20)）；
(62)
A．类型继承
B．类型引用
C．表继承
D．无任何关系
第10题：
下列代码段声明了3个类：
classPerson{)；
classStudent：publicPerson{}；
classUndergraduate：Student{)；
下列关于这些类之间关系的描述中，错误的是（ ）。
A.类Person是类Undergraduate的基类
B.类Undergraduate从类Student公有继承
C.类Student是类Person的派生类
D.类Undergraduate是类Person的派生类
B。【解析】类Undergraduate从类Student私有继承，继承方式缺省则默认是private。