c語言可以實現的簡單程式，很好的運用了結構體，結構體陣列，結構體指標，函式的實現

//contact.h

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#ifndef     __CONTACT_H__
#define     __CONTACT_H__
#define     MAX  1000
#define     MAX_NAME 20
#define     MAX_SEX  5
#define     MAX_TEL  12
#define     MAX_ADDR  20

typedef struct PeoInfor
{
 char name[MAX_NAME];
 char sex[MAX_SEX];
 int age;
 char tel[MAX_TEL];
 char addr[MAX_ADDR];
}PeoInfor;

typedef struct Contact
{
 PeoInfor contact [MAX];
 int count;
}Contact,*pContact;

void InitContact(pContact pcon);
void AddContact(pContact pcon);
void DelContact(pContact pcon);
void SearchContact(pContact pcon);
void ModifyContact(pContact pcon);
void ShowContact(pContact pcon);
void SortContact(pContact pcon);
#endif //

//contact.c
#define _CRT_SECURE_NO_WARNINGS 1
#include "contact.h"
 void InitContact(pContact pcon)
{
 pcon ->count = 0;
 memset(pcon->contact,0,MAX*sizeof(PeoInfor));
}
void AddContact(pContact pcon)
{
 if (pcon->count >=MAX)
 {
  printf ("電話本滿了。\n");
  return ;
 }
 printf ("請輸入姓名>:");
 scanf ("%s",pcon->contact[pcon->count].name);
 printf ("請輸入年齡>:");
 scanf ("%d",&(pcon->contact [pcon->count].age));
 printf ("請輸入性別>:");
 scanf ("%s",pcon->contact [pcon->count].sex);
 printf ("請輸入電話>:");
 scanf ("%s",pcon->contact [pcon->count].tel);
 printf ("請輸入地址>:");
 scanf ("%s",pcon->contact [pcon->count].addr);
 pcon->count ++;
 printf("新增成功\n");
}

int find_entry(pContact pcon,char name[])
{
 int i = 0;
 for (i=0;i<pcon->count;i++)
 {
  if (strcmp(name,pcon->contact[i].name)==0)
   return i;
 }
 return -1;
}

void DelContact(pContact pcon)
{
 char name[MAX_NAME] = {0};
 int pos = 0;
 int i = 0;
 if (pcon->count==0)
 {
  printf ("電話本為空，無法刪除\n");
  return ;
 }
 printf ("請輸入要刪除的人名字>:");
 scanf ("%s",name);
 pos = find_entry(pcon,name);
 if (pos==-1)
 {
  printf ("要刪的人不存在\n");
  return ;
 }
 for (i=pos;i<pcon->count;i++)
 {
  pcon->contact[i] = pcon->contact[i+1]; 
 }
 pcon->count--;
 printf ("刪除成功\n");
}

void SearchContact(pContact pcon)
{
 int pos = 0;
 char name[MAX_NAME] = {0};
 printf ("請輸入你要查詢的人名字\n");
 scanf ("%s",name);
 pos = find_entry(pcon,name);
 if (pos==-1)
 {
  printf ("沒有這個人\n");
  return ;
 }
 else 
 {
   printf ("%10s%5s%6s%7s%8s\n",
        "name","age","sex","tel","addr"  );
  printf ("%10s%5d%6s%7s%8s\n",
   pcon->contact[pos].name,
   pcon->contact[pos].age,
   pcon->contact[pos].sex,
   pcon->contact[pos].tel,
   pcon->contact[pos].addr);
 }
}

void ModifyContact(pContact pcon)
{
 int pos = 0;
 char name[MAX_NAME] = {0};
 int age = 0;
 char sex[MAX_SEX] = {0};
 char tel[MAX_TEL] = {0};
 char addr[MAX_ADDR] = {0};
 printf ("請輸入你要查詢的人名字\n");
 scanf ("%s",name);
 pos = find_entry(pcon,name);
 if (pos==-1)
 {
  printf ("沒有這個人\n");
  return ;
 }
 printf ("請輸入你要改為的名字\n");
 scanf ("%s",name);
 printf ("請輸入你要改為的年齡\n");
 scanf ("%d",&age);
 printf ("請輸入你要改為的性別\n");
 scanf ("%s",sex);
 printf ("請輸入你要改為的電話\n");
 scanf ("%s",tel);
 printf ("請輸入你要改為的地址\n");
 scanf ("%s",addr);
    printf ("%10s%5d%6s%7s%8s\n",
       strcpy(pcon->contact[pos].name,name),
    age,
    strcpy(pcon->contact[pos].sex,sex),
       strcpy(pcon->contact[pos].tel,tel),
    strcpy(pcon->contact[pos].addr,addr));
}

void ShowContact(pContact pcon)
{
 int i = 0;
 printf ("%10s%5s%6s%7s%8s\n","name","age","sex","tel","addr"  );
 for (i=0;i<pcon->count;i++)
 {
  printf ("%10s%5d%6s%7s%8s\n",
   pcon->contact[i].name,
   pcon->contact[i].age,
   pcon->contact[i].sex,
   pcon->contact[i].tel,
   pcon->contact[i].addr);
 }
}
static int cmp(const void *elem1,const void *elem2)
{
  return  strcmp ((*(PeoInfor*)elem1).name ,(*(PeoInfor*)elem2).name );
}

void SortContact(pContact pcon)
{
 int i = 0;
 int sz = sizeof(pcon->contact)/sizeof(pcon->contact[0]);
 qsort (pcon->contact,pcon->count,sizeof (pcon->contact[0]),&cmp); 
  for (i=0;i<pcon->count;i++)
  {
    printf ("%s %d %s %s %s\n",
     pcon->contact[i].name,
     pcon->contact[i].age,
     pcon->contact[i].sex,
     pcon->contact[i].tel,
     pcon->contact[i].addr);
  }
}
      

//test.c

#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include "contact.h"
enum Option
{
 EXIT,
 ADD,
 DEL,
 SEARCH,
 MODIFY,
 SHOW,
 SORT,
};

void menu ()
{
 printf ("***************1.ADD      *******\n");
 printf ("***************2.DEL      *******\n");
 printf ("***************3.SEARCH   *******\n");
 printf ("***************4.MODIFY   *******\n");
 printf ("***************5.SHOW     *******\n");
 printf ("***************6.SORT     *******\n");
 printf ("***************0.EXIT     *******\n");
}

void test ()
{
 int input = 0;
 Contact con = {0} ;
 InitContact(&con);
 do
 {
  menu();
  printf ("請選擇>:");
     scanf ("%d",&input);
  switch (input)
  {
  case ADD:
   AddContact(&con);
   break;
  case DEL:
   DelContact(&con);
   break;
  case SEARCH:
   SearchContact(&con);
   break;
  case MODIFY:
   ModifyContact(&con);
   break;
  case SHOW:
   ShowContact(&con);
   break;
  case SORT:
      SortContact(&con);
   break;
  case EXIT:
   break;
  default :
   printf ("輸入有誤，請重新輸入！\n");
   break;
  }
 }while (input);
}


int main ()
{
 test();
 return 0;
}