C++跳過csv文件的第一行

Question

我得到我的程序從.csv文件讀取並輸出數據，但我不希望它輸出第一行。我試過使用getline(data, line);和stream.ignore (std::numeric_limits<std::streamsize>::max(), '\n');。儘管它沒有跳過第一行，但最後兩行打印兩次並混合起來。

string ID; 
string sentenceIn; 
string servedIn; 
int sentence; 
int served; 
string lastName; 
string firstName; 

vector<string> idNum; 
vector<string> sentenceLen; 
vector<string> servedTime; 
vector<string> lastNameIn; 
vector<string> firstNameIn; 


ifstream data("prisoner_data.csv"); 

if (data.is_open()) 
{ 
    cout << "File opened successfully." << endl << endl; 
    while (data.good()) // !someStream.eof() 
    { 
     getline(data, ID, ','); 
     cout << ID << " "; 
     idNum.push_back(ID); 

     getline(data, sentenceIn, ','); 
     cout << sentenceIn << " "; 
     sentenceLen.push_back(sentenceIn); 
     istringstream(sentenceIn) >> sentence; 

     getline(data, servedIn, ','); 
     cout << servedIn << " "; 
     servedTime.push_back(servedIn); 
     istringstream(servedIn) >> served; 

     getline(data, lastName, ','); 
     lastNameIn.push_back(lastName); 
     cout << lastName << " "; 

     getline(data, firstName, ','); 
     firstNameIn.push_back(firstName); 
     cout << firstName << " "; 
    } 
} 

我能做些什麼，以跳過不搞亂了最後的第一行？

Answer 1

while (data.good())很腥。你最終會「吃」多一行。見例如Why is iostream::eof inside a loop condition considered wrong?瞭解更多詳情。通常你直接在while測試的getline的結果，就像

while(getline(data, line)){...} 

一個可能的解決方案是用while(getline(data, line)){...}到逐行讀取文件中的行，然後用stringstream(line)和每行，再次與getline解析它，現在分開,。要跳過第一行，請先執行getline(data, line);，然後再執行while(getdata(data, line)){ /* process line */}。一個簡單的例子如下：

#include <iostream> 
#include <string> 
#include <fstream> 
#include <sstream> 
#include <cstdlib> 

int main() 
{  
    std::ifstream data("prisoner_data.csv"); 
    if (!data.is_open()) 
    { 
     std::exit(EXIT_FAILURE); 
    } 
    std::string str; 
    std::getline(data, str); // skip the first line 
    while (std::getline(data, str)) 
    { 
     std::istringstream iss(str); 
     std::string token; 
     while (std::getline(iss, token, ',')) 
     { 
      // process each token 
      std::cout << token << " "; 
     } 
     std::cout << std::endl; 
    } 
}