std::ifstream 和读取文件

Question

So I've been stuck with a problem for a while now and I can't figure out why it's not working. It is probably something really stupid that I've forgotten about but I'm having a huge problem reading from a file located in my project.

I'm trying to use "res/dir/file.txt" as a filepath but it wont work. I've also tried to move the file for "file.txt" filepath, but nothing. I've been moving the file around all over the project to see if can reach it from somewhere but with no success. The working directory is $(ProjectDir)

streamFile("res/dir/file.txt");

My function looks something like this and I'm not able to enter the while loop with (getline(stream, line)) which is my major indicator to the problem:

void streamFile(const std::string& filepath)
{
    std::ifstream stream(filepath);
    std::string line;
    while (getline(stream, line))
    {
        if (line.find("#Example") != std::string::npos)
        {

        }
        else
        {

        }
    }   
    return;
}

I feel really stupid atm because I know that I've done this before and never had a similar problem. What am I missing?

Answer 1

Your code works perfectly fine. I tried it out this way:

#include <iostream>
#include <fstream>

int main(void)
{
  std::ifstream stream("./res/dir/test.txt");
  std::cout << (stream.is_open() ? "file successfully opened" : "file could not be opened") << std::endl;
  std::string line;
  while (getline(stream, line))
  {
    std::cout << "line read: " << line << std::endl;
    if (line.find("my") != std::string::npos)
    {
      std::cout << "\t ... found magic word" << std::endl;
    }
    else
    {
      std::cout << "\t ... no magic word in this line" << std::endl;
    }
  }
}

./res/dir/test.txt

hello world
my name is john doe
how are you?

The output is as expected:

file successfully opened
line read: hello world
     ... no magic word in this line
line read: my name is john doe
     ... found magic word
line read: how are you?
     ... no magic word in this line