Getline随机停止工作

Question

我正在尝试编写一个非常基本的程序来读取CSV并显示它。如下所示，该功能是一个非常基本的功能。在显示每个单元格之前，它使用getline读取每一行（直到换行符）。它工作正常，当getline完全停止工作时，我正在调整循环以显示每个单元格。在不更改任何与getline相关的代码的情况下，我编译了它并且它不会从文件中读取。行总是空的。但是，ifstream是有效的，因为“test”字符串（我在响应中插入）从sheet fine中读入。任何人都可以帮助我吗？

PS：之前我遇到过与getline类似的问题。这与我的系统有关吗？它似乎可以开启和关闭

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

using namespace std;

int main(int argc, char *argv[])
{
ifstream sheet( "StockTake.csv", ios::app );
if ( ! sheet.is_open() )
{
    cout << "Cannot Open File!\n";
    return 0;
}
else
{
    cout << "Opened File\n";
}
//Now print each row (find the newline chracter at the end of each line)
/*string test;
sheet >> test;
cout << test;*/
for ( string row; ! sheet.eof(); getline(sheet, row, '\n') )
{
    if (row == "")
    {
        cout << "Bad Read.  Exiting\n";
        return 0;
    }
    //Print out each row with a tab space between each cell
    string cell;
    //find the beginning and the end of each cell
    for (int i = 0, j = 0; ; )
    {
        /*Checks if the cell is enclosed in quotes
        The first time, j == i hence the -2 and +2
        the +2 is required to "skip" out the apostrophes if
        they are found*/
        if (row.at(i) == '"')
        {
            i++;
            j = i-2;
            do
            {
                j = row.find('"', j+2);
            } while (row.at(j+1) == '"');
            /*Check for the "" apostrophe sign*/
        }
        else
        {
            j = row.find(',', i);
        }
        /*Print the Cell*/
        if (j == string::npos) //if this is the last cell
        {
            cell = row.substr(i, row.size() - i);
        }
        else if ( j-i != 0)
        {
            cell = row.substr(i, j-i);
        }
        else
        {
            cell = "";
        }
        /*Check for the "" apostrophe sign, and replace
        with " for each instance*/
        if ( cell.find("\"\"", 0) != string::npos )
        {
            int pos = -2; //must start at zero
            do
            {
                //Skips out the "current" apostrophe
                //if there are more than one
                pos = cell.find("\"\"", pos+2);
                cell = cell.substr(0, pos) + 
                       cell.substr(pos+1, cell.size()- (pos+1) );
            } while (cell.find("\"\"", pos+2) != string::npos);

        }
        /*Display the Cell, only the space will be displayed
        if the cell is empty*/
        cout << cell << "     ";
        /*Find the next cell*/
        if ( row.at(j) == '"' )
        {
            i = j+2;
        }
        else
        {
            i = j+1;
        }

    }
    cout << "\n"; //Print newline character at the end of each line
}
return 0;
}