#include<iostream>
#include<fstream>
#include<string>
#include<vector>
#include<cstdlib>
#include"Sales_Date.h"
using namespace std;
 
int main(void)
{
    Sales_Date total;
    ifstream op_File("haibo.txt",ios::in|ios::out);
    char line[100];

    if(!op_File) cout << "error!";
    op_File.getline(line,100);

    if(read(cin>>line,total))
    {   
        Sales_Date trans;
        op_File.getline(line,100);

        while(read(cin>>line,trans))
        {
            op_File.getline(line,100);
            if(total.isbn() == trans.isbn())
                (trans);
            else total = trans;
        }
        print(cout,total) << endl;
    }

    else {cerr << "error!\n";}

    op_File.close();
    system("pause");
    return 0;
}

没有这本书，也没有Sales_Date.h，帮不了你

我觉得你还是应该把Sales_Date.h贴出来，编译环境和错误代码都贴出来好点