read multiple files with quite similar names c++ - c++-cli

Question

I am reading a file from current directory
ifstream myfile;
myfile.open("version1.1.hex");
Now a situation is arising that if user updates version then there will be version1.2.hex or version1.3.hex ..so on in the current directory, but one file at a time will be present. I want to write a code now which will cater this future need of reading different file.
I'm writing this code in C++/CLI.

Answer 1

Since file listings are a bit environment-dependant I am not sure if this is helpful to you,
but here is an example how to achieve your goal under the mircosoft regime.
What is needed is the FindFirstFile / FindNextFile calls which query all files matching the fileSearchKey. Then you can use the cFileName part of WIN32_FIND_DATAA as parameter to your open command
string fileSearchKey = "version*";
WIN32_FIND_DATAA fd;
bool bFirstRun = true;
bool bFinishedRun = false;
HANDLE h = INVALID_HANDLE_VALUE;
while (!bFinishedRun)
{
if (bFirstRun)
{
h = FindFirstFileA(fileSearchKey.c_str(), &fd);
bFirstRun = false;
} else
{
if (FindNextFileA(h, &fd) != FALSE)
{
// Abort with error because it has more than one file or decide for the most recent version
} else
{
bFinishedRun = true;
}
}
}
// Load file
ifstream myfile;
myfile.open(fd.cFileName);

Answer 2

This code will look in the directory and take the first file, then quit.
WARNING : this will work only on linux
#include <iostream>
#include <string>
#include <vector>
#include <stdio.h>
#include <cstring>
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <unistd.h>
using namespace std;
int main ()
{
char n[20];
unsigned char isFolder = 0x4;
unsigned char isFile = 0x8;
DIR *dir;
struct dirent *ent;
dir = opendir ("./");
if (dir != NULL) {
/* print all the files and directories within directory */
while ((ent = readdir (dir)) != NULL) {
//folder sign
if(ent->d_type != isFolder && string(ent->d_name).find("version") != string::npos)
{
cout <<ent->d_name <<"\n";
// Your code
break;
}
}
closedir (dir);
} else {
/* could not open directory */
perror ("");
return 0;
}
cout << "=========" << endl;
}

Answer 3

In C++/CLI you should use the .net framework libraries for this. For instance you can use Directory::GetFiles.
using namespace System;
using namespace System::IO;
int main(array<System::String ^> ^args)
{
array<String^>^dirs = Directory::GetFiles(".", "version1.*.hex");
Collections::IEnumerator^ myEnum = dirs->GetEnumerator();
while (myEnum->MoveNext())
{
Console::WriteLine(myEnum->Current);
}
return 0;
}