#include<iostream.h>
#include<stdio.h>
#include<process.h>
#include<stdlib.h>
#define MAX 5
//定義結(jié)構(gòu)類型
struct student {
       int  num;
       char name[20];
       float grade;
};

//顯示student結(jié)構(gòu)數(shù)據(jù)
void show_str(student a,char *name) {
    cout<<name<<":"<<endl;
    cout<<a.num<<" "<<a.name<<" "<<a.grade;
    cout<<endl;
}

//main函數(shù)測試結(jié)構(gòu)數(shù)據(jù)的文件讀寫
int main(void) 
{ 
    //聲明變量
    FILE *fp;    
    //聲明FILE結(jié)構(gòu)指針變量 
    student st={1001,"ZhangBin",85.5};

    //顯示st結(jié)構(gòu)數(shù)據(jù)
    show_str(st,"st");

    //打開d.dat文件
    if ((fp=fopen("d.dat","wb+"))==NULL)
    {
       cout<<"\nCould not open the file."<<endl;
       cout<<"Exiting program."<<endl;
       exit(1);   //結(jié)束程序執(zhí)行
    }

    //用fprintf()函數(shù)寫結(jié)構(gòu)數(shù)據(jù)到文件
    fprintf(fp,"%d %s %f",st.num,st.name,st.grade);

    rewind(fp);   //恢復(fù)讀寫指針的位置

    //用fscanf()函數(shù)讀文件中的數(shù)據(jù)賦值給結(jié)構(gòu)并顯示
    student temp;
    fscanf(fp, "%d %s %f",&temp.num,temp.name,&temp.grade);
    show_str(temp,"temp");
    cout<<"-----------------------"<<endl;

    fclose(fp); // 關(guān)閉文件

    //將結(jié)構(gòu)數(shù)據(jù)當(dāng)成數(shù)據(jù)塊進(jìn)行讀寫
    if ((fp=fopen("d1.dat","wb+"))==NULL)  //打開d1.dat文件
    {
       cout<<"\nCould not open the file."<<endl;
       cout<<"Exiting program."<<endl;
       exit(1);   //結(jié)束程序執(zhí)行
    }

    //聲明結(jié)構(gòu)數(shù)組并初始化
    int i;
    student starr[3]={{101,"WangPing",92},{102,"Li",85},{103,"LiuMin",97}};

    //顯示結(jié)構(gòu)數(shù)組
    for(i=0;i<3;i++) 
        show_str(starr[i],"starr");

    //將結(jié)構(gòu)數(shù)組當(dāng)成數(shù)據(jù)塊寫入文件
    fwrite(starr, sizeof(student), 3, fp);

    rewind(fp);   //恢復(fù)讀寫指針的位置

    //按數(shù)據(jù)塊從文件中讀取數(shù)據(jù)賦值給結(jié)構(gòu)數(shù)組
    student temp_arr[3];
    if (!feof(fp))    //使用feof()判斷文件尾 
         fread(temp_arr, sizeof(student),3,fp);
    for(i=0;i<3;i++) 
        show_str(temp_arr[i],"temp_arr");
    
    fclose(fp); // 關(guān)閉文件
}