• 文件操作(结构体写入失败)


    /***
    write.c
    ***/
    #include<stdio.h>
    #include<string.h>
    
    struct student
    {
        char name[10];
        int age;
    };
    
    int main()
    {
        struct student st[10] = {0};
        int i;
        for(i = 0; i < 10; i++)
        {
            printf("please input name:
    ");
            scanf("%s",st[i].name);
            printf("please input age:
    ");
            scanf("%d",&st[i].age);
        }
        FILE *p = fopen("./a.txt","w");
        fwrite(st,sizeof(struct student),10,p);
        fclose(p);
    }
    #include<stdio.h>
    #include<string.h>
    
    struct student
    {
        char name[100];
        int age;
    };
    
    int main()
    {
        struct student st = {0};
        FILE *p = fopen("./a.txt","rb");
        while(!feof(p))
        {
            memset(&st,0,sizeof(struct student));
            fread(&st,sizeof(struct student),1,p);
            printf("name = %s , age = %d
    ",st.name,st.age);
        }
        fclose(p);
        return 0;
    }

    read运行结果读取的数据不对。

    /***
    
    write.c
    
    ***/
    
    #include<stdio.h>
    
    #include<string.h>
    
     
    
    struct student
    
    {
    
           char name[10];
    
           int age;
    
    };
    
     
    
    int main()
    
    {
    
           struct student st[10] = {0};
    
           int i;
    
           for(i = 0; i < 10; i++)
    
           {
    
                  printf("please input name:
    ");
    
                  scanf("%s",st[i].name);
    
                  printf("please input age:
    ");
    
                  scanf("%d",&st[i].age);
    
           }
    
           FILE *p = fopen("./a.txt","w");
    
           fwrite(st,sizeof(struct student),10,p);
    
           fclose(p);
    
    }

    以下程序读取成功:

    // write.c
    #include<stdio.h> #include<string.h> struct student { char name[100]; int age; }; int main() { struct student st[3] = {0}; int i; for(i = 0; i < 3; i++) { scanf("%s",st[i].name); scanf("%d",&st[i].age); } FILE * p = fopen("./c.txt","wb"); fwrite(&st,sizeof(st),3,p); fclose(p); return 0; }
    //read.c
    #include<stdio.h>
    #include<string.h>
    
    struct student
    {
        char name[100];
        int age;
    };
    
    int main()
    {
        struct student st[3] = {0};
        //FILE *p = fopen("./a.dat","rb");
        FILE *p = fopen("./c.txt","rb");
        int i;
        //while(!feof(p))
        for(i = 0; i < 3; i++)
        {
            //memset(&st,0,sizeof(struct student));
            fread(&st[i],sizeof(struct student),1,p);
            printf("name = %s , age = %d
    ",st[i].name,st[i].age);
        }
        fclose(p);
        return 0;
    }
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  • 原文地址:https://www.cnblogs.com/wanghao-boke/p/11246067.html
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