要了解此页面上的所有程序,您应该了解以下主题。
- C数组
- C指针
- 数组和指针关系
- 文件I / O
C文件示例
1. C程序读取n个学生的姓名和分数并将其存储在文件中。
#include
int main()
{
char name[50];
int marks, i, num;
printf("Enter number of students: ");
scanf("%d", &num);
FILE *fptr;
fptr = (fopen("C:\\student.txt", "w"));
if(fptr == NULL)
{
printf("Error!");
exit(1);
}
for(i = 0; i < num; ++i)
{
printf("For student%d\nEnter name: ", i+1);
scanf("%s", name);
printf("Enter marks: ");
scanf("%d", &marks);
fprintf(fptr,"\nName: %s \nMarks=%d \n", name, marks);
}
fclose(fptr);
return 0;
}
2. C程序从中读取n个学生的姓名和分数并将其存储在文件中。如果文件先前已退出,则将信息添加到文件中。
#include
int main()
{
char name[50];
int marks, i, num;
printf("Enter number of students: ");
scanf("%d", &num);
FILE *fptr;
fptr = (fopen("C:\\student.txt", "a"));
if(fptr == NULL)
{
printf("Error!");
exit(1);
}
for(i = 0; i < num; ++i)
{
printf("For student%d\nEnter name: ", i+1);
scanf("%s", name);
printf("Enter marks: ");
scanf("%d", &marks);
fprintf(fptr,"\nName: %s \nMarks=%d \n", name, marks);
}
fclose(fptr);
return 0;
}
3. C程序使用fwrite()将结构数组的所有成员写入文件。从文件中读取阵列并显示在屏幕上。
#include
struct student
{
char name[50];
int height;
};
int main(){
struct student stud1[5], stud2[5];
FILE *fptr;
int i;
fptr = fopen("file.txt","wb");
for(i = 0; i < 5; ++i)
{
fflush(stdin);
printf("Enter name: ");
gets(stud1[i].name);
printf("Enter height: ");
scanf("%d", &stud1[i].height);
}
fwrite(stud1, sizeof(stud1), 1, fptr);
fclose(fptr);
fptr = fopen("file.txt", "rb");
fread(stud2, sizeof(stud2), 1, fptr);
for(i = 0; i < 5; ++i)
{
printf("Name: %s\nHeight: %d", stud2[i].name, stud2[i].height);
}
fclose(fptr);
}