将学生结构体写入文件 

  1 #include <stdio.h>
  2 #include <string.h>
  3 struct Student
  4 {
  5     char m_name[20];    //姓名
  6     int m_age;          //年龄
  7     int m_height;       //身高
  8 };
  9 typedef struct Student Student_t;
 10 
 11 void Student_Print(const Student_t *v,int len)
 12 {
 13     for(int i = 0; i < len ; i++)
 14     {
 15         printf("姓名:%s\t年龄:%d\t身高:%d\n",v[i].m_name,v[i].m_age,v[i].m_height);
 16     }
 17     printf("－－－－－－－－－－－－－－－－－－－－－－－－－－\n");
 18 }
 19 
 20 void sort(Student_t *v,int len,int (*cmp)(void *,void *))
 21 {
 22     Student_t temp;
 23     for(int i = 0; i < len ;i++)
 24     {
 25         for(int j = 0; j < len - 1;j++)
 26         {
 27             if(cmp(&v[j],&v[j+1]) > 0)
 28             {
 29                 //swap
 30                 temp = v[j];
 31                 v[j] = v[j+1];
 32                 v[j+1] = temp;
 33             }
 34         }
 35     }
 36 }
 37 
 38 int Student_age(void *data_1,void *data_2)
 39 {
 40     Student_t *num_1 = data_1;
 41     Student_t *num_2 = data_2;
 42 
 43     return num_1->m_age - num_2->m_age;
 44 }
 45 
 46 
 47 int Student_name(void *data_1,void *data_2)
 48 {
 49     Student_t *num_1 = data_1;
 50     Student_t *num_2 = data_2;
 51 
 52     return strcmp(num_1->m_name,num_2->m_name);
 53 }
 54 
 55 int Student_height(void *data_1,void *data_2)
 56 {
 57     Student_t *num_1 = data_1;
 58     Student_t *num_2 = data_2;
 59 
 60     return num_1->m_height - num_2->m_height;
 61 }
 62 
 63 int Student_age_height(void *data_1,void *data_2)
 64 {
 65     Student_t *num_1 = data_1;
 66     Student_t *num_2 = data_2;
 67     if(num_1->m_age - num_2->m_age == 0)
 68     {
 69         return num_1->m_height - num_2->m_height;
 70     }
 71 
 72     return num_1->m_age - num_2->m_age;
 73 }
 74 
 75 int main()
 76 {
 77 #if 0
 78     Student_t stu[] = {{"张三",18,165},{"李四",20,170},{"王五",17,155},{"周六",19,190},{"磊磊",20,180},{"麻子",17,180},{"马云",18,160}};
 79 #else
 80     Student_t stu[7];
 81     memset(stu,0,sizeof(stu));  //清空操作
 82 #endif
 83     int len = sizeof(stu) / sizeof(stu[0]);
 84     Student_Print(stu,len);
 85     //sort(stu,len,Student_age);    //年龄的升序
 86     //sort(stu,len,Student_name);    //姓名的升序
 87     //sort(stu,len,Student_height);    //身高的升序
 88     FILE *fp = NULL;
 89     fp = fopen("Student.txt","r+");
 90     if(fp == NULL)
 91     {
 92         printf("打开文件失败:\n");
 93         return -1;
 94     }
 95 #if 0
 96     sort(stu,len,Student_age_height);   //先排年龄后排身高
 97     for(int i = 0 ; i < len;i++)
 98     {
 99         fprintf(fp,"%s %d %d\n",stu[i].m_name,stu[i].m_age,stu[i].m_height);
100     }
101 #else
102     for(int i = 0 ; i < len;i++)
103     {
104         fscanf(fp,"%s %d %d\n",stu[i].m_name,&stu[i].m_age,&stu[i].m_height);
105     }
106 #endif
107     Student_Print(stu,len);
108 
109     fclose(fp);
110 
111     return 0;
112 }

 

posted @ 2021-03-03 23:53  王廷胡_白嫖帝  阅读(118)  评论(0)    收藏  举报