如何通过值从列表中删除对象

时间:2019-09-29 15:35:13

标签: python-3.x

我的问题是我创建了一个带有姓名和号码的学生列表。现在的任务是按学生的号码删除该学生。我的问题是我的代码无法正常工作。

另一个问题是它总是显示内存地址而不是对象的值。

预先感谢

班级学生:

def __init__(self, name, number):
    self.name = name
    self.number = number

从.student导入Student 课程:

def __init__(self, name, code, credit, student_limit):
    self.name = name
    self.code = code
    self.credit = credit
    self.student_limit = student_limit

students = []
def add_student(self, new_student):
    self.student = new_student
    self.students.append(new_student)
    print("Student added" +str(self.students))

def remove_student_by_number(self, student_number):
    self.student_number = student_number
    if student_number in self.students: self.students.remove(student_number)
    print("Student removed" + str(self.students))

来自.course导入课程 班系:

def __init__(self, name, code):
       self.name = name
       self.code = code

courses = []       
def add_course(self, course):
    self.course = course
    self.courses.append(course)
    print("Course added" +str(self.courses))

从python导入* def main():

alice = Student("Alice", 1336)
bob = Student("Bob", 1337)

math_dept = Department("Mathematics and Applied Mathematics", "MAM")

math_course = Course("Mathematics 1000", "MAM1000W", 1, 10)

math_dept.add_course(math_course)

math_course.add_student(bob)
math_course.add_student(alice)

math_course.remove_student_by_number(alice.number)

if __name__ == "__main__":
main()

1 个答案:

答案 0 :(得分:1)

self.studentsStudent实例的列表,因此如果未实现方法__str__(例如,请参见here),它将打印实例的内存地址。您应该尝试显式打印每个属性,例如student.namestudent.number

无论如何,您都试图在student_number的列表中找到Student,因此,它绝不会运行删除行。而是使用if student_number in [student.number for student in self.students]来查找学生的号码列表,而不是学生列表本身。但是,在这种情况下,您还想删除以student_number作为输入的学生,因此您可能需要使用如下循环:

def remove_student_by_number(self, student_number):
    for student in self.students:
        if student.number == student_number:
            print("Student removed" + str(student.name))
            self.students.remove(student)
            break