结构体二级指针案例

#define _CRT_SECURE_NO_WARNINGS
#include "stdio.h"
#include "stdlib.h"
#include "string.h"

typedef struct _Teacher
{
	char*name;
	char**student;	//创建学生数组
}Teacher;

void allocateTeacherSpace(Teacher***tArr,int num)
{
	Teacher**TeacherArr = malloc(sizeof(Teacher*)*num);//创建num个Teacher*

	for (int i = 0; i < num;i++)
	{
		//给每个Teacher*开辟空间
		TeacherArr[i] = malloc(sizeof(Teacher));
		//给每个Teacher成员开辟空间
		TeacherArr[i]->name = malloc(128);
		TeacherArr[i]->student = malloc(sizeof(char*) * 5);
		for (int j = 0; j < 5; j++)
		{
			TeacherArr[i]->student[j] = malloc(128);
		}
	}
	*tArr = TeacherArr;
}

void nameTeacher(Teacher**tArr,int num)
{
	for (int i = 0 ; i < num; i++)
	{
		char buf[128] = { 0 };
		sprintf(buf, "Teacher_%d", i + 1);
		strcpy(tArr[i]->name, buf);
		for (int j = 0; j < 5; j++)
		{
			sprintf(buf, "T_%d_S_%d", i + 1, j + 1);
			strcpy(tArr[i]->student[j], buf);
		}
	}
}

void printMsg(Teacher**tArr, int num)
{
	for (int i = 0; i < num;i++)
	{
		printf("%s\n", tArr[i]->name);
		for (int j = 0; j < 5; j++)
		{
			printf("%s\t\t", tArr[i]->student[j]);
		}
		printf("\n\n");
	}
}

void freeMem(Teacher***tArr,int num)
{
	Teacher**pTeacher = *tArr;
	if (pTeacher==NULL)
	{
		return;
	}
	for (int i = 0; i < num; i++)
	{
		for (int j = 0; j < 5; j++)
		{
			free(pTeacher[i]->student[j]);
			pTeacher[i]->student[j] = NULL;
			printf("释放T%d的学生S%d的内存\n", i + 1, j + 1);
		}
		free(pTeacher[i]->name);
		pTeacher[i]->name = NULL;
		printf("释放T%d的name内存\n", i + 1);
		free(pTeacher[i]->student);
		pTeacher[i]->student = NULL;
		printf("释放T%d的student内存\n", i + 1);
		free(pTeacher[i]);
		pTeacher[i] = NULL;
		printf("释放T%d的内存\n", i + 1);
	}
	free(pTeacher);
	printf("释放Teacher的内存\n");
	*tArr = NULL;
}

void test11()
{
	//堆区创建Teacher数组
	Teacher**tArr = NULL;
	int tNum = 9;
	allocateTeacherSpace(&tArr, tNum);
	//给Teacher数组赋值
	nameTeacher(tArr, tNum);
	printMsg(tArr, tNum);
	freeMem(&tArr, tNum);
}

int main()
{
	test11();
	system("pause");
	return 0;
}