Python复杂对象转json

Python复杂对象转json

python不常用, 出了岔子, 想将几个实体转成json, 但是因为实体列表里的实体里面套实体列表...直接使用json.dumps(obj)会出现一些错误, 只能给里面的列表添加的时候调用object.__dict__, 但是外层使用object.__dict__就会报错, 很迷, 大概就是里面的元素无法序列化, 或者是某一个属性无法找到对应的"key".

嗐, 直接上代码:

# 其实这么写就可以了=.=
json.dumps(obj=self.students,
            default=lambda x : x.__dict__, sort_keys=False, indent=2)

这里是一个小Demo:

import json

class Course:

    def __init__(self, courseNum, courseName, courseCredit):
        self.CourseNum = courseNum
        self.CourseName = courseName
        self.CourseCredit = courseCredit

class Student:

    def __init__(self, studentNum, studentName, *courses):
        self.StudentNum = studentNum
        self.StudentName = studentName
        self.Courses = []
        self.Courses += courses

class IStudentResp(object):

    def AddStudent(self, student):
        pass

    def SelectStudent(self, studentNum):
        pass

    def DeleteStudent(self, studentNum):
        pass

    def AddCourse(self, studentNum, course):
        pass

    def SelectCourse(self, studentNum, courseNum):
        pass

    def DeleteCourse(self, studentNum, courseNum):
        pass

class StudentResp(IStudentResp):
    students = []
    def __init__(self):
        pass

    def AddStudent(self, student):
        self.students.append(student)

    def SelectStudent(self, studentNum):
        for stu in self.students:
            if studentNum == stu.StudentNum:
                return stu

    def DeleteStudent(self, studentNum):
        self.students.remove(self.SelectStudent(studentNum))

    def AddCourse(self, studentNum, course):
        self.SelectStudent(studentNum).Courses.append(course)

    def SelectCourse(self, studentNum, courseNum):
        for stu in self.students:
            if stu.StudentNum == studentNum:
                for course in stu.Courses:
                    if course.CourseNum == courseNum:
                        return course

    def DeleteCourse(self, studentNum, courseNum):
        self.SelectStudent(studentNum).Courses\
            .remove(self.SelectCourse(studentNum, courseNum))

    def show(self):
        print(json.dumps(obj=self.students,
            default=lambda x : x.__dict__, sort_keys=False, indent=2))
        # print(json.dumps(self.students))

if __name__ == "__main__":
    sp = StudentResp()
    sp.AddStudent(Student("001", "001", Course("A", "A", 2), Course("A", "A", 2)))
    sp.AddStudent(Student("002", "001", Course("A", "A", 2), Course("A", "A", 2)))
    sp.AddStudent(Student("003", "001", Course("A", "A", 2), Course("A", "A", 2)))
    sp.AddStudent(Student("004", "001", Course("A", "A", 2), Course("A", "A", 2)))
    sp.AddCourse("001", Course("A", "A", 2))
    sp.AddCourse("001", Course("A", "A", 2))
    sp.AddCourse("001", Course("A", "A", 2))
    sp.AddCourse("001", Course("A", "A", 2))

    sp.show()