用python实现简易学生管理系统

以前用C++和Java写过学生管理系统，也想用Python试试，果然“人生苦短，我用Python”。用Python写的更加简洁，实现雏形也就不到100行代码。
下面上代码
  1 #!/usr/bin/python3
  2 # coding=utf-8
  3 
  4 
  5 # 实现switch-case语句
  6 class switch(object):
  7     def __init__(self, value):
  8         self.value = value
  9         self.fall = False
 10 
 11     def __iter__(self):
 12         """Return the match method once, then stop"""
 13         yield self.match
 14         raise StopIteration
 15 
 16     def match(self, *args):
 17         """Indicate whether or not to enter a case suite"""
 18         if self.fall or not args:
 19             return True
 20         elif self.value in args:  # changed for v1.5, see below
 21             self.fall = True
 22             return True
 23         else:
 24             return False
 25 
 26 
 27 class student:
 28     def __init__(self, name, age, id, grade):
 29         self.next = None
 30         self.name = name
 31         self.age = age
 32         self.id = id
 33         self.grade = grade
 34 
 35     def show(self):
 36         print('name:', self.name, ' ', 'age:', self.age, ' ', 'id:', self.id, ' ', 'grade:', self.grade)
 37 
 38 
 39 class stulist:
 40     def __init__(self):
 41         self.head = student('', 0, 0, 0)
 42 
 43     def display(self):
 44         p = self.head.next
 45         if p==None:
 46             print('no student data in database!')
 47         while p:
 48             p.show()
 49             p = p.next
 50 
 51 
 52     def insert(self):
 53         print('please enter:')
 54         name = input('name:')
 55         age = input('age:')
 56         id = input('id:')
 57         grade = input('grade:')
 58         newstu = student(name, age, id, grade)
 59         p = self.head
 60         while p.next:
 61             p = p.next
 62         p.next = newstu
 63 
 64     def query(self):
 65         name = input('please enter the name you want to query:')
 66         p = self.head.next
 67         if p==None:
 68             print('no such student in database')
 69         while p:
 70             if p.name == name:
 71                 p.show()
 72             p = p.next
 73 
 74     def delete(self):
 75         name = input("please enter the student'name you want to delete:")
 76         p = self.head.next
 77         pre = self.head
 78         while p:
 79             if p.name == name:
 80                 pre.next = p.next
 81                 p.next = None
 82                 print('the student info has been deleted!')
 83                 break
 84             else:
 85                 pre = p
 86                 p = p.next
 87 
 88 
 89 def main():
 90     stulist1 = stulist()
 91     user_input = input('please enter the OPcode:')
 92     while user_input:
 93         print('a--insert/b--display/c--query/h or ''--help/d--delete')
 94         for case in switch(user_input):
 95             if case('a'):
 96                 stulist1.insert()
 97                 user_input = input('please enter the OPcode:')
 98                 break
 99             if case('b'):
100                 stulist1.display()
101                 user_input = input('please enter the OPcode:')
102                 break
103             if case('c'):
104                 stulist1.query()
105                 user_input = input('please enter the OPcode:')
106                 break
107             if case('d'):
108                 stulist1.delete()
109                 user_input = input('please enter your OPcode:')
110                 break
111             if case():  # default
112                 print('please enter the OPcode...')
113                 user_input = input('please enter the OPcode:')
114                 break
115 
116 
117 if __name__ == "__main__":
118     main()
下面是运行结果：