文件IO從文件

Question

讀取多種類型的可以說我有這樣的

6 3 
john 
dan 
lammar 

我可以閱讀數字的文本文件，我可以讀的名字，只有當他們在不同的文件。但是這裏的數字和名字都在一個文件中。我如何忽略第一行並直接從第二行開始閱讀？

int main() 
{ 
vector<string> names; 
fstream myFile; 
string line; 
int x,y; 
myFile.open("test.txt"); 
    //Im using this for reading the numbers 
while(myFile>>x>>y){} 
//Would use this for name reading if it was just names in the file 
while(getline(myFile,line)) 
    names.push_back(line); 
cout<<names[0]; 
return 0; 
} 

Answer 1

如果您使用fstream的只是調用忽略（）方法：

istream& ignore (streamsize n = 1, int delim = EOF); 

所以它變得非常簡單：

ifstream file(filename); 
file.ignore(numeric_limits<streamsize>::max(), '\n'); // ignore the first line 

// read the second line 
string name; getline(flie, name); 

Answer 2

我不知道我是否有你的權利但如果你總是想跳過第一行 - 你可以簡單地跳過它？

int main() 
{ 
    vector<string> names; 
    fstream myFile; 
    string line; 
    int x,y; 
    myFile.open("test.txt"); 
    //skip the first line 
    myFile>>x>>y; 
    //Would use this for name reading if it was just names in the file 
    while(getline(myFile,line)) 
    names.push_back(line); 
    cout<<names[0]; 
    return 0; 
} 

Answer 3

嘗試這樣：

int main() 
{ 
    std::vector<std::string> names; 
    std::fstream myFile; 
    myFile.open("test.txt"); 
    if(myFile.is_open()) 
    { 
     std::string line; 

     if (std::getline(myFile, line)) 
     { 
      std::istringstream strm(line); 

      int x, y; 
      strm >> x >> y; 

      while (std::getline(myFile, line)) 
       names.push_back(line); 
     } 

     myFile.close(); 

     if(!names.empty()) 
      std::cout << names[0]; 
    } 
    return 0; 
}