Question

c++如何以空格和换行符为间隔读取文件中的字符串？

文件中的字符串排列方式如下：
001 student2 student1
003 student2 student1 student3
008 student3

想要读取到如下vector中：
struct Course
{
char ID[5];
vector<char*>Stulist;
};
vector<Course>vecCourse;

以下代码执行后无输出，感觉是读换行符那边出了点问题，但不知道怎么改
FILE *pfile = NULL;
fopen_s(&pfile, "d:\\data_stu\\coursemember.txt", "r");
if (pfile == NULL)
{
printf("error!\n");
exit(0);
}
Course course;//新建一个Course型变量用于临时存放文件中读出的数据
char *stuname;
while (1)
{
fscanf_s(pfile, "%s", course.ID, 5);
if (feof(pfile)) break;//文件结束退出循环
while (1)
{
char *stuname = new char;//确保每次push进Stulist的地址不同
char ch = fgetc(pfile);
if (ch != '\n')//判断是否换行
{
fscanf_s(pfile, "%s", stuname);
course.Stulist.push_back(stuname);
}
delete stuname;
if (ch == '\n') break;//退出内层循环
}
vecCourse.push_back(course)//;将course推入vector
}
fclose(pfile);

//输出刚才导入的内容
for (unsigned int i = 0; i < vecCourse.size(); i++)
{
cout << vecCourse[i].ID << "\t";
unsigned int j = 0;
for (; j < vecCourse[i].Stulist.size()-1; j++)
{
cout << vecCourse[i].Stulist[j] << " ";
}
cout << vecCourse[i].Stulist[j] << endl;
}

Answer 1

//给你改了下，改动的地方都有注释：

#include<stdio.h>

#include<stdlib.h>

#include <iostream>

#include <vector>

using namespace std;

struct Course

{

char ID[5];

vector<char*>Stulist;

};

int main()

{

vector<Course>vecCourse;

FILE *pfile = NULL;

fopen_s(&pfile, "d:\\data_stu\\coursemember.txt", "r");

if (pfile == NULL)

{

printf("error!\n");

exit(0);

}

Course course;

char *stuname;

char buffer[200];  //临时空间

while (1)

{

fscanf_s(pfile, "%s", course.ID, 5);

if (feof(pfile)) break;

while (1)

{      

char ch = fgetc(pfile);

if (ch != '\n')

{

fscanf_s(pfile, "%s", buffer);   //先读到buffer里

stuname = new char[strlen(buffer)+1];  //申请适当的空间

strcpy(stuname, buffer);     //复制

course.Stulist.push_back(stuname);

}

//delete stuname;  //这就是vecCourser里的链接,不能释放

if (ch == '\n') break;

}

vecCourse.push_back(course);

course.Stulist.clear();  //清理临时course

}

fclose(pfile);

for (unsigned int i = 0; i < vecCourse.size(); i++)

{

cout << vecCourse[i].ID << "\t";

unsigned int j = 0;

for (; j < vecCourse[i].Stulist.size(); j++)  //不-1

{

cout << vecCourse[i].Stulist[j] << " ";

}

cout << endl;  //换行

}

for (unsigned int i = 0; i < vecCourse.size(); i++)

{

unsigned int j = 0;

for (; j < vecCourse[i].Stulist.size(); j++)  

{

delete[] vecCourse[i].Stulist[j] ;   //释放

}

}

}

运行：