C项目（文件链表实现管理系统）

项目核心

管理系统的三大块：内存模型，数据库模型，人机交互界面。

将链表作为内存数据模型，将文件作为数据库，将终端作为交互界面。读文件生成链表，修改链表写入文件。

初始化数据库 此时数据库是文件
读取数据库，生成内存数据模型
增，删，改，查，排序
更新数据库，退出程序

代码实现

#define  _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#include <string.h>



typedef struct student  //数据节点
{
	char name[30];
	char sex;
	int age;
	float score;
}Stu;

typedef struct _StuNode      //链表节点
{
	Stu data;               // 数据域
	struct _StuNode* next;  // 指针域
}StuNode;

void InitData2File()         //初始化数据库     此时数据库是文件
{
	Stu s[4] =
	{
		"liudehua",'x',50,100,
		"zhangxueyou",'x', 60,89,
		"guofucheng",'m',50,88,
		"liming",'f',50,90,
	};
	FILE* pf = fopen("stu.data", "w+");
	if (NULL == pf)
		exit(-1);
	fwrite((void*)s, sizeof(s), 1, pf);
	fclose(pf);
	return;
}

StuNode* CreatListFronFile(const char* filePath) //创建文件链表
{
	FILE* pf = fopen(filePath, "r+");
	if (NULL == pf)
		exit(-1);
	StuNode* head = (StuNode*)malloc(sizeof(StuNode));
	head->next = NULL;
	StuNode* tmp = (StuNode*)malloc(sizeof(StuNode));
	while (fread((void*)&tmp->data, sizeof(Stu), 1, pf)) //1    0
	{
		tmp->next = head->next;
		head->next = tmp;
		tmp = (StuNode*)malloc(sizeof(StuNode));
	}
	free(tmp);
	return head;
}

void TraverseStuList(StuNode* head)   //遍历链表
{
	printf("\n\t\t\t========================================================\n");
	printf("\t\t\tname\t\tsex\t\tage\t\tscore\n");
	head = head->next;
	while (head)
	{
		printf("\t\t\t%-10s\t%c\t\t%d\t\t%.2f\n", head->data.name, head->data.sex, head->data.age, head->data.score);
		head = head->next;
	}
	printf("\n\t\t\t========================================================\n");
}

void addListStuNode(StuNode* head)   //增加链表节点
{
	StuNode* tmp = (StuNode*)malloc(sizeof(StuNode));
	printf("name :");
	scanf("%s", tmp->data.name);

	getchar();
	printf("sex  :");
	scanf("%c", &tmp->data.sex);

	getchar();
	printf("age  :");
	scanf("%d", &tmp->data.age);

	getchar();
	printf("score:");
	scanf("%f", &tmp->data.score);

	tmp->next = head->next;
	head->next = tmp;
}

StuNode* SearchStuNode(StuNode* head)   //查找链表节点
{
	printf("please input search name:");
	char name[30];
	scanf("%s", name);
	head = head->next;
	while (head)
	{
		if (strcmp(head->data.name, name) == 0)
		break;
		head = head->next;
	}
	return head;
}


void DeleteListStuNode(StuNode* head)  //删除链表节点
{
	StuNode* tmp = SearchStuNode(head);
	if (!tmp)
	{
		printf("删除的用户不存在\n");
		printf("按任意键返回!\n");
		getchar();
		getchar();
	}
	else
	{
		StuNode* deletePrior = head;
		while (deletePrior->next != tmp)
		{
			deletePrior = deletePrior->next;
		}
		deletePrior->next = tmp->next;
		free(tmp);
	}
}


int lenListStu(StuNode* head)    //求链表长度
{
	int len = 0;
	head = head->next;
	while (head)
	{
		len++;
		head = head->next;
	}
	return len;
}
void SortListStu(StuNode* head)    //链表排序
{
	int len = lenListStu(head);
	StuNode* prep, * p, * q;
	for (int i = 0; i < len - 1; i++)
	{
		prep = head;
		p = prep->next;
		q = p->next;
		for (int j = 0; j < len - 1 - i; j++)
		{
			if (strcmp(p->data.name,q->data.name)>0)
			{
				prep->next = q;
				p->next = q->next;
				q->next = p;

				prep = q;
				q = p->next;
				continue;
			}
			prep = prep->next;
			p = p->next;
			q = q->next;
		}
	}
}

void SaveList2File(StuNode* head,const char * filePath) //更新数据库
{
	FILE * pf = fopen(filePath, "w+");
	if (NULL == pf)
		exit(-1);
	head = head->next;
	while (head)
	{
		fwrite((void *)&head->data,sizeof(Stu),1,pf);
		head = head->next;
	}
	fclose(pf);
}
void DestroyListStu(StuNode* head)   //销毁链表
{
	StuNode* tmp;
	while (head)
	{
		tmp = head;
		head = head->next;
		free(tmp);
	}
}
int main()
{
	//InitData2File();
	StuNode* head = CreatListFronFile("stu.data");
	while (1)
	{
		system("cls");
		TraverseStuList(head);
		printf("\n1-->add\t\t2-->search\t3-->delete\t4-->sort\t5-->exit\n");
		int choice;
		printf("please input choice:");
		scanf("%d", &choice);
		StuNode* FindNode;
		switch (choice)
		{
		case 1:
			addListStuNode(head);
			break;
		case 2:
			
			if (FindNode = SearchStuNode(head))
			{
				printf("find success\n");
				printf("\t\t\t%-10s\t%c\t\t%d\t\t%.2f\n", FindNode->data.name,
					FindNode->data.sex, FindNode->data.age, FindNode->data.score);
			}
			else
			{
				printf("no find");
			}
			printf("按任意键返回!\n");
			getchar();
			getchar();

			break;
		case 3:
			DeleteListStuNode(head);

			break;
		case 4:
			SortListStu(head);
			break;
		case 5:
			SaveList2File(head,"stu.data");
			DestroyListStu(head);
			return 0;
		default:
			printf("输入错误\n");
		}
	}
	return 0;
}

测试结果