程序支持增加、查询、删除、存盘和读取操作
1. 头文件studentsys.h定义如下
/* student management system by list */ #ifndef _StudentSys_H #define _StudentSys_H #define MAX 25 /* lenth of name string */ typedef struct _Grade Grade;; typedef struct StdNode Std;; typedef struct ListNode *List;
全局结构体定义
/* 6 courses */ struct _Grade{ int Chinese; int Math; int English; int Programming; int Physic; int Geology; }; /* student info */ struct StdNode { int Id; /* student id */ char name[MAX];/* student name */ Grade grades; /* student grades */ }; struct ListNode { Std info; List next; };
函数声明
/* 1->Add 2->Find 3->Del 4->Brows 5->Store
6->Read 7->DelAll 8->Cls 9->Quit */ 功能选择键
int AddStd( List L, int Id, char *name, Grade grades ); /* flag:0 by id, 1 by name */ int FindStd(List L, int flag, int Id ,char *name); int DeleteStd( List L, int Id ); void PrintInfo( List L ); void PrintAll( List L ); int StoreInfo( List L ); List ReadInfo( ); void DestoryInfo( List L ); int IsRepeat( List L, int Id ); void selectInfo();
2. 源文件studentsys.c
主体部分，由while循环下的switch分支进行功能选择
#include <stdio.h> #include <string.h> #include <stdlib.h> #include "studentsys.h" int main(void) { List L; /* Head Node */ L = (List)malloc(sizeof( struct ListNode )); L->next = NULL; int i, flag; /* flag做为查找方式标志， 0由Id, 1由姓名进行搜索 */ int option, Id = 0; /* option选择功能， init info */ char name[MAX]= " "; Grade grades; printf(" Starting \n"); printf(" Student Management system, ver:0.101 \n"); printf("******************************************************\n"); printf(" 学生管理系统\n"); printf("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$\n"); selectInfo(); while ( 1 ) { scanf("%d", &option); switch ( option ) { case 1: printf("Please in put id, name, six grades:\n"); scanf("%d %s", &Id, name); scanf("%d %d %d %d %d %d", &grades.Chinese, &grades.Math, &grades.English, &grades.Programming,&grades.Physic, &grades.Geology ); if ( AddStd( L, Id, name, grades ) == 1 ) { printf("Added student.\n"); } else { printf("Sorry, can‘t add student\n"); } break; case 2: printf("select method: 0 by Id, 1 by name\n"); scanf("%d", &flag); printf("Please in put id, name\n"); scanf("%d %s", &Id, name); /* notice & */ if ( FindStd( L, flag, Id, name ) == 1 ) { printf("found student\n"); } else { printf("sorry, can‘t found student\n"); } break; case 3: printf("Which id you want ot del: "); scanf("%d", &Id); if ( DeleteStd( L, Id ) ) { printf("Successfully Delete!\n"); } else { printf(" Not found!\n"); } break; case 4: PrintAll( L ); break; case 5: if ( StoreInfo( L ) ) { printf("Write successfulluy!\n"); } else { printf("Failed to read!\n"); } break; case 6: L = ReadInfo( ); break; case 7: DestoryInfo( L ); break; case 8: system("cls"); selectInfo(); break; case 9: exit(0); break; default: printf("error!请重新输入!\n"); } } return 0; }
函数主体，由简单的链表的插入删除遍历实int AddStd( List L, int Id, char *name, Grade grades ){
List Head = L; List Cur; if( IsRepeat( L, Id)==1 ) { printf(" Id repeat!!!\n"); return 0; } Cur = (List)malloc(sizeof( struct ListNode )); if ( Cur != NULL ) { Cur->info.Id = Id; strcpy( Cur->info.name, name); Cur->info.grades.Chinese = grades.Chinese; Cur->info.grades.Math = grades.Math; Cur->info.grades.English = grades.English; Cur->info.grades.Programming = grades.Programming; Cur->info.grades.Physic = grades.Physic; Cur->info.grades.Geology = grades.Geology; Cur->next = Head->next; Head->next = Cur; return 1; } else { printf("Failed to malloc!\n"); return 0; } } int FindStd( List L, int flag, int Id , char *name ) { List Cur = L->next; while ( Cur != NULL ) { if( flag == 1 ) { if ( strcmp( name, Cur->info.name ) == 0 ) { PrintInfo(Cur); break; } } else if ( flag == 0 ) { if ( Cur->info.Id == Id ) { PrintInfo(Cur); break; } } Cur = Cur->next; } if ( Cur == NULL ){ return 0; } else { return 1; } } int DeleteStd( List L, int Id ) { List Pre = L; List Cur = Pre->next; if( L->next == NULL ) { printf("Empty Node!\n"); return 0; } else { while ( Cur != NULL ) { if ( Cur->info.Id == Id ) { /* 找到对应编号 */ Pre->next = Cur->next; free(Cur); break; } Pre = Cur; Cur = Cur->next; } if ( Cur == NULL ) { return 0; } else { return 1; } } /* 1 else */ } void PrintInfo( List L ) { List Cur = L; if ( Cur != NULL ) { printf("ID: %d ", Cur->info.Id); printf("Name: %s\n", Cur->info.name); printf("Chinese :%d ", Cur->info.grades.Chinese); printf("Math :%d ", Cur->info.grades.Math); printf("English :%d\n", Cur->info.grades.English); printf("Programming:%d ", Cur->info.grades.Programming); printf("Physic :%d ", Cur->info.grades.Physic); printf("Geology :%d\n", Cur->info.grades.Geology); } } void PrintAll( List L ) { List Cur = L->next; int i = 0; while ( Cur != NULL ) { i++; printf("%d-->Student ", i); PrintInfo( Cur ); Cur = Cur->next; } } void DestoryInfo( List L ) { List Cur, Tmp; Cur = L->next; while ( Cur != NULL ) { Tmp = Cur->next; free( Cur ); Cur = Tmp; } L->next = NULL; printf("删除所有学生信息成功!\n"); } int IsRepeat( List L, int Id ) { List Cur = L->next; int flag = 0; while ( Cur != NULL ) { if ( Cur->info.Id == Id ) {
flag = 1；
break;
}
Cur = Cur->next;
}
return flag; } void selectInfo() { printf("Stumansys 请选择：\n"); printf("(1)---增加学生 (2)---查询学生 (3)---删除学生 \n"); printf("(4)---查看全部 (5)---记录存盘 (6)---读取信息\n"); printf("(7)---删除所有 (8)---清除屏幕 (9)---退出系统\n"); }
文件读写操作
1. 链表写入文件，每次写一个结构体，直到链表尾。
2 .文件读取，使用feof(fp)函数判断是否达到文件流尾，否则读取一个结构体，并尾插入链表
int StoreInfo( List L ) { FILE *fp = fopen("student.data", "w"); List H = L->next; const int size = 1; int ret = -1; /* default */ if ( fp == NULL ) { printf("Failed to open file!\n"); } else if( H == NULL ) { printf("Empty student info!\n"); } else { /* write list into fp */ while ( H != NULL ) { ret = fwrite( H, sizeof(H->info), size, fp ); H = H->next; } ret = 1; } fclose( fp ); return ret; } List ReadInfo( ) { int i = 0; /* count */ List L, P, tmp; P = L = (List)malloc( sizeof(struct ListNode) ); FILE *fp = fopen("student.data", "r"); if ( fp == NULL ) { printf("Failed to read file!\n"); return NULL; } /* 假如文件为空,检查文件结束符 feof在到达文件流尾返回非零值 */ if ( feof(fp) != 0 ) { tmp = (List)malloc( sizeof(struct ListNode) ); fread( tmp, sizeof(tmp->info), 1, fp); if( feof(fp) ) { printf("读取失败!文件为空!\n"); free(tmp); } return(NULL); } while ( feof(fp) == 0 ) { tmp = (List)malloc( sizeof(struct ListNode) ); fread( tmp, sizeof(tmp->info), 1, fp); printf("正在读取第%d个数据\n", ++i); if ( feof(fp) != 0 ) { /* reached end */ free(tmp); break; } /* List tail insert */ P->next = tmp; P = tmp; P->next = NULL; } fclose(fp); printf("Read successfulluy!\n"); return L; }