python Student Information Management System (Full version)

2020-12-20 03:40:52
OfStack

This paper is based on the previous one (python project: Student Information Management System (first edition)), and has been improved and added new functions.

It mainly includes:

Perfect part: Input error; There are no data queries and other exception errors

New features: Operations on files: reads and writes to files, with emphasis on detailed parsing of text strings (see the code for full parsing and reorganization, as well as adding comments)

Student Information Management System (Full version)

Student information management project, with operation interface, and complete each operation:

The detailed code is as follows:


# student_info.py
#  Student information management project, with operation interface, and complete each operation: 
#  + -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- + 
#  | 1) add student information | 
#  | 2) display all student information | 
#  | 3) delete student information | 
#  | 4) modify student information | 
#  | 5) display | of student information according to high - low student scores 
#  | 6) display | of student information according to low to high scores of students 
#  | 7) display | of student information according to student age 
#  | 8) display | of student information according to low - high student age 
#  |   9) Save student information to the file ( students.txt)  | 
#  |   10) Read data from a file ( students.txt)  | 
#  |   Exit: any other key < enter >   | 
#  + -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- +   | 
 
 
def meun():
 menu_info = ''' + -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- + 
 |   1) Add student information   | 
 |   2) Display the information of all students   | 
 |   3) Delete student information   | 
 |   4) Modify student information   | 
 |   5) Display student information according to high - low scores   | 
 |   6) Display student information according to low - high student performance   | 
 |   7) Display student information according to student age   | 
 |   8) Display student information by age   | 
 |   9) Save student information to the file ( students.txt)  | 
 |   10) Read data from a file ( students.txt)  | 
 |   Exit: any other key < enter >   | 
 + -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- + 
'''
 print(menu_info)
 
 
#  The following 2 A function is used to sorted Sorting, key Expression function of 
def get_age(*l):
 for x in l:
 return x.get("age")
def get_score(*l):
 for x in l:
 return x.get("score")
 
#  1) Add student information 
def add_student_info():
 L = []
 while True:
 n = input(" Please enter your name: ")
 if not n: #  Jump out of the loop with the name null 
 break
 try:
 a = int(input(" Please enter your age: "))
 s = int(input(" Please enter your score: "))
 except:
 print(" Invalid input, not shaping value... Reentry information ")
 continue
 info = {"name":n,"age":a,"score":s}
 L.append(info)
 print(" Student information input finished!! ")
 return L
 
#  2) Display the information of all students 
def show_student_info(student_info):
 if not student_info:
 print(" According to countless sources... ")
 return
 print(" The name ".center(8)," age ".center(4)," results ".center(4))
 for info in student_info:
 print(info.get("name").center(10),str(info.get("age")).center(4),str(info.get("score")).center(4))
 
#  3) Delete student information 
def del_student_info(student_info,del_name = ''):
 if not del_name:
 del_name = input(" Please enter the deleted student name: ")
 for info in student_info:
 if del_name == info.get("name"):
 return info
 raise IndexError(" Student information does not match , Could not find %s" %del_name)
 
#  4) Modify student information 
def mod_student_info(student_info):
 mod_name = input(" Please enter the modified student name: ")
 for info in student_info:
 if mod_name == info.get("name"):
 a = int(input(" Please enter your age: "))
 s = int(input(" Please enter your score: "))
 info = {"name":mod_name,"age":a,"score":s}
 return info
 raise IndexError(" Student information does not match , Could not find %s" %mod_name)
 
#  5) Display student information according to high - low scores 
def score_reduce(student_info):
 print(" Students are shown by high - low scores ")
 mit = sorted(student_info ,key = get_score,reverse = True)
 show_student_info(mit)
 
#  6) Display student information according to low - high student performance 
def score_rise(student_info):
 print(" Show students' low - high scores ")
 mit = sorted(student_info ,key = get_score)
 show_student_info(mit)
 
#  7) Display student information according to student age 
def age_reduce(student_info): 
 print(" High and low by student age: ")
 mit = sorted(student_info ,key = get_age,reverse = True)
 show_student_info(mit)
 
#  8) Display student information by age 
def age_rise(student_info): 
 print(" Low to high by student age: ")
 mit = sorted(student_info ,key = get_age)
 show_student_info(mit)
 
#  9) Save student information to the file ( students.txt)
def save_info(student_info):
 try:
 students_txt = open("students.txt","w") #  Open in write mode and empty the contents of the file 
 except Exception as e:
 students_txt = open("students.txt", "x") #  The file does not exist. Create the file and open it 
 for info in student_info:
 students_txt.write(str(info)+"\n") #  Store by line, adding a newline character 
 students_txt.close()
 
#  10) Read data from a file ( students.txt) 
def read_info():
 old_info = []
 try:
 students_txt = open("students.txt")
 except:
 print(" No data information has been saved ") #  Failed to open. File does not exist. No data saved 
 return
 while True:
 info = students_txt.readline()
 if not info:
 break
 # print(info)
 info = info.rstrip() # Get rid of newline characters 
 # print(info)
 info = info[1:-1] #  Remove the {} 
 # print(info)
 student_dict = {} #  Individual student dictionary information 
 for x in info.split(","): #  Split at intervals of theta and theta 
 # print(x)
 key_value = [] #  Open up space, key_value[0] save key,key_value[0] save value
 for k in x.split(":"): #  Divide by: 
 k = k.strip() # Remove the first and last null characters 
 # print(k)
 if k[0] == k[-1] and len(k) > 2: #  Determines whether it is a string or an integer 
 key_value.append(k[1:-1]) #  Get rid of the first and the last. 
 else:
 key_value.append(int(k))
 # print(key_value)
 student_dict[key_value[0]] = key_value[1] #  Student information addition 
 # print(student_dict)
 old_info.append(student_dict) #  Summary of all student information 
 students_txt.close() 
 return old_info 
 
def main():
 student_info = []
 while True:
 # print(student_info)
 meun()
 number = input(" Please enter options: ")
 if number == '1':
 student_info = add_student_info()
 elif number == '2':
 show_student_info(student_info)
 elif number == '3':
 try:
 student_info.remove(del_student_info(student_info))
 except Exception as e:
 #  The student names do not match 
 print(e) 
 elif number == '4':
 try: 
 student = mod_student_info(student_info)
 except Exception as e:
 #  The student names do not match 
 print(e)
 else:
 #  First, delete the student from the list according to the name entered, and then re-add the student's latest information 
 student_info.remove(del_student_info(student_info,del_name = student.get("name"))) 
 student_info.append(student)
 elif number == '5':
 score_reduce(student_info)
 elif number == '6':
 score_rise(student_info)
 elif number == '7':
 age_reduce(student_info)
 elif number == '8':
 age_rise(student_info)
 elif number == '9':
 save_info(student_info)
 elif number == '10':
 student_info = read_info()
 else:
 break
 input(" Enter displays the menu ")
 
main()

For more information about the management system, please click "Management system Topics" to learn