移动互联网开发实践seo搜索引擎优化师

本篇文章主要是实现一个简易的通讯录：

功能如下：

1. 添加用户
2. 修改用户
3. 删除用户
4. 查找用户（可重名）
5. 按名字或年龄排序
6. 显示用户
7. 保存通讯录
8. 日志追加

 有如下知识点：

1. 动态数组
2. 结构体
3. 枚举
4. 自定义标识符和宏
5. 文件打开与存储
6. 函数
7. 指针
8. 循环 
9. 排序

简述特点：

1. 将人员信息放在一个PeoInf的结构体中，再创建一个结构体List，用于存放peoinf这个结构体的指针，和容量与目前通讯录人员数量。
2. 再用realloc动态开辟以结构体peoinf为大小的内存，用于实现动态内存开辟。
3. 程序运行后，初始化这段空间，并查询是否有“contact.txt”的文件存在，如果存在，则读取文件里的内容，并放到peoinf的结构体“数组”中，并实时监控是否需要扩容。如果不存在就创建文件。
4. 随后就可以添加、修改、查找、删除用户，每一次增删改查都会被记录到一个“contact_log.txt”的文件里，这里使用了时间戳。
5. 用qsort进行名字或年龄进行排序
6. 程序会知道本次是否进行修改，如果修改后就退出会提示是否需要保存，当然也可以自己手动保存。
7. 程序以“rb”和“wb”进行文件的读写。
8. 程序实现了重名查找，在有重名的情况下会进行选择。
9. （代码可直接运行，复制到编译器vs2019即可）

代码部分

1. contact.h

   #pragma once
   #include <stdio.h>
   #include <string.h>
   #include <stdlib.h>
   #include <errno.h>
   #include <assert.h>
   #include <time.h>
   #include <sys/stat.h>#define MAX_10 10
   #define MAX_20 20
   //#define LOG_PRINT(x) fprintf(pf, "In %s %s ,user %s name calling %s\n",__DATE__,__TIME__,(x),(list->pl+num)->name)
   typedef struct PeoInf
   {char name[MAX_20];int age;char sex[5];char tel[12];char addr[30];
   }PeoInf;
   //定义通讯录结构体，嵌套PeoInf
   typedef struct List
   {//动态内存分配PeoInf* pl;int count;int capacity;//容量
   }List;
   //定义一个枚举变量，用于存储菜单所有选择
   enum select_all
   {EXIT,//0ADD,DEL,SELECT,MODIFY,SORT,SHOW,SAVE
   };
   //菜单函数
   void menu();
   //定义初始化list函数
   void initialise_list(List* list);
   //定义添加信息函数
   void add_peoinf(List* list);
   //定义显示函数
   void show_list(List* list);
   //定义删除函数
   void del_peoinf(List* list);
   //定义通过找名字查找人的函数（已实现重名查找）
   int find_byname(const List* list);
   //定义查找人
   void sele_peoinf(const List* list);
   //定义修改人信息函数
   void modify_peoinf(List* list);
   //定义删除和修改已找到下标的信息函数
   void del_havefond(List* list, int position);
   void modify_havefond(List* list, int position);
   //定义排序函数
   void sort_peoinf(List* list);
   //定义文件保存函数
   void file_save(List* list);
   //定义扩容函数
   void expand_list(List* list);

2. actualize.c

   #include "contact.h"
   //实现菜单函数
   void menu(){printf("----------------------------------------\n");printf("--------1. add      2. del--------------\n");printf("--------3. select   4. modify-----------\n");printf("--------5. sort     6. show-------------\n");printf("--------------7. save-------------------\n");printf("--------------0. exit-------------------\n");printf("----------------------------------------\n");
   }
   //实现初始化list函数
   void initialise_list(List* list){PeoInf* ptr = (PeoInf*)calloc(3, sizeof(PeoInf));//默认开辟三个人的存储空间if (ptr == NULL) {printf("%s", strerror(errno));return ;}list->pl = ptr;list->count = 0;list->capacity = 3;FILE* pf = NULL;struct stat buffer;//判断文件是否存在if (stat("contact.txt", &buffer) != 0) {//不存在就创建文件pf = fopen("contact.txt", "wb");fclose(pf);pf = NULL;return;}pf = fopen("contact.txt", "rb");if (pf != NULL) {for (int i = 0; fread(list->pl + i, sizeof(PeoInf), 1, pf) != 0; i++) {if (list->count == list->capacity - 1) {expand_list(list);}list->count++;}fclose(pf);}pf = NULL;
   }
   //扩容函数
   void expand_list(List* list) {PeoInf* ptr =(PeoInf*) realloc(list->pl, (list->capacity + 2)*sizeof(PeoInf));//每次增加两个if (ptr == NULL) {printf("%s", strerror(errno));return;}list->pl = ptr;list->capacity += 2;
   }
   //实现添加日志功能
   /*
   * return 0 失败
   * return 1 成功
   */
   int add_log(List* list,char* moving,int num) {//打开文件FILE* pf=NULL;//判断写入模式是否要追加if (list->count == 0) {pf = fopen("contact_log.txt", "w");}else {pf = fopen("contact_log.txt", "a");}//如果打开失败，报错if (pf == NULL) {perror("fopen:");return 0;}//获取时间戳time_t rawtime;struct tm* timeinfo;time(&rawtime);timeinfo = localtime(&rawtime);fprintf(pf, "In %s \tuser %s name calling %s.\n", asctime(timeinfo), moving, (list->pl + num)->name);fclose(pf);pf = NULL;return 1;
   }
   //实现添加信息功能
   void add_peoinf(List* list) {assert(list);//断言//判断是否需要扩容if (list->count == list->capacity) {expand_list(list);//内部函数，不必去头文件里定义printf("Automatic capacity expansion is successful,\n and the current address book capacity is %d\n", list->capacity);}printf("Please enter the name\n->");scanf("%s", (list->pl+list->count)->name);printf("Please enter age\n->");scanf("%d", &(list->pl + list->count)->age);printf("Please enter sex\n->");scanf("%s", (list->pl + list->count)->sex);printf("Please enter the telephone\n->");scanf("%s", (list->pl + list->count)->tel);printf("Please enter the address\n->");scanf("%s", (list->pl + list->count)->addr);//添加日志log功能if (!add_log(list,"add",list->count)) {printf("log fail,please find excause.\n");}list->count++;printf("succeed！\n");
   }
   //实现显示函数
   void show_list(List* list) {assert(list);printf("name\tage\tsex\ttelephone\taddr\n");for (int i = 0; i < (list->count); i++) {printf("%s\t%d\t%s\t%s\t\t%s\n", (list->pl + i)->name,(list->pl + i)->age, (list->pl + i)->sex, (list->pl + i)->tel, (list->pl + i)->addr);}
   }
   //实现通过寻找名字，找到这个人
   //重名默认存放数组为10，如需变大可改为动态扩容实现
   int find_byname(const List* list) {char s_name[MAX_20] = { 0 };int count = 0;int find_result[MAX_10] = { 0 };printf("Please enter the name that you want \n->");scanf("%s", s_name);for (int i = 0; i < list->count; i++) {if (strcmp((list->pl + i)->name, s_name)==0) {//找到了if (count == 0) {printf("Find the information, please confirm\n");printf("number\tname\tage\tsex\ttelephone\taddr\n");}printf("%d\t%s\t%d\t%s\t%s\t\t%s\n", count+1,(list->pl + i)->name,(list->pl + i)->age, (list->pl + i)->sex, (list->pl + i)->tel, (list->pl + i)->addr);find_result[count] = i;//将找到的坐标存入数组中count++;//判断是否有重复}}if (count == 0) {//找不到printf("Check no such person, please confirm after the input!\n");return -1;}else if (count == 1) {return find_result[0];}else {//两个以上int select_num = 0;while (1) {printf("Please select the object serial number that you want to operate on\n->");scanf("%d", &select_num);if (select_num >= 1 && select_num <= count) {//输入正确序号，方可返回return find_result[select_num - 1];}else {printf("error,please reenter\n");}}}
   }
   //实现删除函数
   void del_peoinf(List* list) {assert(list);int del_num = find_byname(list);if (del_num < 0) return;//查找失败for (int i = 0; i < list->count - del_num - 1; i++) {*(list->pl + del_num + i) = *(list->pl + del_num + 1 + i);}list->count--;printf("delet successfully\n");if (!add_log(list, "delet", del_num)) {printf("log fail,please find excause.\n");}
   }
   void del_havefond(List* list,int position) {assert(list);for (int i = 0; i < list->count - position - 1; i++) {*(list->pl + position + i) = *(list->pl + position + 1 + i);}list->count--;printf("delet successfully\n");if (!add_log(list, "delet", position)) {printf("log fail,please find excause.\n");}
   }
   //实现查找信息功能
   void sele_peoinf(const List* list) {assert(list);int find_num = find_byname(list);if (find_num < 0) return;//查找失败printf("The information is as follows\n");printf("name\tage\tsex\ttelephone\taddr\n");printf("%s\t%d\t%s\t%s\t\t%s\n", (list->pl + find_num)->name,(list->pl + find_num)->age, (list->pl + find_num)->sex, (list->pl + find_num)->tel, (list->pl + find_num)->addr);int input_find = 0;do {printf("--------------------------------\n");printf("--------------------------------\n");printf("-----1. del-------2. modif------\n");printf("------------0. exit-------------\n");printf("--------------------------------\n");printf("--------------------------------\n");printf("please enter what you want\n->");scanf("%d", &input_find);if (input_find == 1) {del_havefond(list, find_num);return;}else if (input_find == 2) {modify_havefond(list, find_num);return;}else if (input_find != 0) {printf("Input is wrong, please reagain\n");}} while (input_find);}
   void modify_havefond(List* list,int position) {assert(list);printf("Please enter the new name\n->");scanf("%s", (list->pl + position)->name);printf("Please enter new age\n->");scanf("%d", &(list->pl + position)->age);printf("Please enter new sex\n->");scanf("%s", (list->pl + position)->sex);printf("Please enter the new telephone\n->");scanf("%s", (list->pl + position)->tel);printf("Please enter the new address\n->");scanf("%s", (list->pl + position)->addr);printf("Modified successfully\n");if (!add_log(list, "modify", position)) {printf("log fail,please find excause.\n");}
   }
   //实现修改信息
   void modify_peoinf(List* list) {assert(list);int mod_num = find_byname(list);if (mod_num < 0) return;//查找失败printf("Please enter the new name\n->");scanf("%s", (list->pl + mod_num)->name);printf("Please enter new age\n->");scanf("%d", &(list->pl + mod_num)->age);printf("Please enter new sex\n->");scanf("%s", (list->pl + mod_num)->sex);printf("Please enter the new telephone\n->");scanf("%s", (list->pl + mod_num)->tel);printf("Please enter the new address\n->");scanf("%s", (list->pl + mod_num)->addr);printf("Modified successfully\n");if (!add_log(list, "modify",mod_num)) {printf("log fail,please find excause.\n");}
   }
   //qsort的比较函数
   int compare_name(const void* e1,const void* e2) {return strcmp(((PeoInf*)e1)->name, ((PeoInf*)e2)->name);}
   int compare_age(const void* e1, const void* e2) {return ((PeoInf*)e1)->age - ((PeoInf*)e2)->age;}
   //实现排序函数
   void sort_peoinf(List* list) {int sort_input = 0;do {printf("--------------------------------\n");printf("--------------------------------\n");printf("-----1. name-------2. age------\n");printf("------------0. exit-------------\n");printf("--------------------------------\n");printf("--------------------------------\n");printf("please enter you want sort by\n->");scanf("%d", &sort_input);if (sort_input == 1) {qsort(list->pl, list->count, sizeof(PeoInf), compare_name);printf("sort by name successfully\n");return;}else if (sort_input == 2) {qsort(list->pl, list->count, sizeof(PeoInf), compare_age);printf("sort by age successfully\n");return;}} while (sort_input);}
   void file_save(List *list) {FILE* pf = fopen("contact.txt", "wb");//二进制写入if (pf == NULL) {perror("fopen:");return;}//写数据for (int i = 0; i < list->count; i++) {fwrite(list->pl+i, sizeof(PeoInf), 1, pf);}fclose(pf);pf = NULL;
   }

3. test.c

   #include "contact.h"
   int main()
   {int input = 0;List list;initialise_list(&list);//动态内存开辟，记得用完销毁int modify_num = 0;//修改数量记录do{menu();printf("Please choose!\n->");scanf("%d", &input);switch (input){case ADD: {add_peoinf(&list);modify_num++;}break;case DEL:{del_peoinf(&list);modify_num++;}break;case SELECT:{sele_peoinf(&list);}break;case MODIFY:{modify_peoinf(&list);modify_num++;}break;case SORT:{sort_peoinf(&list);}break;case SHOW:{show_list(&list);}break;case SAVE:{file_save(&list);printf("save in file sucessfully\n");modify_num = 0;}break;case EXIT:{if (modify_num != 0) {int save_select = 0;printf("=========1.save   2.no=============\n");printf("The modified data is not saved, whether it needs to be saved\n->");scanf("%d", &save_select);if (save_select == 1) {file_save(&list);printf("save in file sucessfully\n");}}printf("Ok,have a nice day! Bye~");}break;default:printf("Input is wrong,please reagain!\n");break;}} while (input);//销毁动态内存free(list.pl);list.pl = NULL;
   }

希望对大家有帮助！