C# - 建構子(Constructor)

學習重點:

• 建構子(Constructor)無輸出型別
• 建構子的名稱需與class的名稱相同
• 多載(Overloaded): 允許相同建構子擁有不同的引數個數

主程式:       

        private void button1_Click(object sender, EventArgs e)

        {

            Student s1 = new Student(6, "小王");          // 建立物件s1

            Student s2 = new Student(3, "小三");          // 建立物件s2

            Student s3 = new Student(5, "小三", "MIT");   // 建立物件s3

            MessageBox.Show(s1.say());

            MessageBox.Show(s2.say());

            MessageBox.Show(s3.say());

        }

Student 類別  :

    class Student

    {

        //屬性

        public int grade;

        public String name;

        public String school;

        //建構子1

        public Student(int sgrade, String sname)

        {

            grade = sgrade;

            name = sname;

            school = "哈佛"; //重複指定

        }

        //建構子2 (多載)

        public Student(int sgrade, String sname, String sschool)

        {

            grade = sgrade;

            name = sname;

            school = sschool;

        }

        //方法1- 自我介紹

        public String say()

        {

            return "我叫" + name + "就讀於" + school + grade + "年級" ;

        }  

    } 

執行結果: