编写函数打开文件用于输入，将文件内容读入string类型的Vector容器，每一行存储为该容器对象的一个元素

#include <iostream>
#include <fstream>
#include <string>
#include <vector>
using namespace std;

int fileToVector(string fileName, vector<string> &svec)
{
 ifstream inFile(fileName.c_str());
 if(!inFile)
 {
  return 1;
 }
 string s;
 while(getline(inFile, s))
  svec.push_back(s);
 inFile.close();
 if(inFile.eof())
  return 4;
 if(inFile.bad())
  return 3;
 if(inFile.fail())
  return 2;
}

int main()
{
 string fileName, s;
 vector<string> svec;
 cout << "Enter file name; " << endl;
 cin >> fileName;

 switch(fileToVector(fileName, svec))
 {
 case 1:
  cout << "error: can not open file" << fileName << endl;
  return -1;
 case 2:
  cout << "error: read failure" << endl;
  return -1;
 case 3:
  cout << "error: system failure" << endl;
  return -1;
 }
 cout << "Vector:" << endl;
 for (vector<string>::const_iterator it = svec.begin(); it != svec.end(); ++it)
  cout << *it << endl;
 return 0;
}