How to check if a string given as input is a valid directory in C++ using Boost Libraries?

Question

I am using Dev-C++ Ide for coding and I want to check if a string given as input is a valid existing directory or not in C++, I referred to these posts on StackOverflow but I couldn't find a solution that I could understand - How to check if directory exist using C++ and winAPI one returns true in all case so no use) can anyone help me out with this problem?

Give code, expected output, your actual output. Also, depending on what version of Dev-C++ you have installed, it may be severely outdated. — , Aug 21 '14 at 17:32
Are you suggesting that a winapi call does not work? Sounds a little unlikely, given the amount of testing it has had... — Martin James, Aug 21 '14 at 17:32
`I couldn't find a solution that I could understand ` So how are we to know what you understand? The solutions given at that link were very simple, especially the one that got a rep of 30. — PaulMcKenzie, Aug 21 '14 at 17:34
I am new to using this so can you like tell me given the input as a string parameter how to tell if its a directory or not? — AnkitSablok, Aug 21 '14 at 17:35
@AnkitSablok - The solution is right there on the page you have a link to. It is the very first answer -- it didn't get 30 upvotes for nothing. — PaulMcKenzie, Aug 21 '14 at 17:36

score 0 · Answer 1 · answered Aug 21 '14 at 17:32

You may find this useful : http://msdn.microsoft.com/en-us/library/bb773584%28VS.85%29.aspx

Pasting example :

#include <windows.h>
#include <iostream.h>
#include "Shlwapi.h"

void main(void)
{
    // Valid file path name (file is there).
    char buffer_1[ ] = "C:\\TEST\\file.txt"; 
    char *lpStr1;
    lpStr1 = buffer_1;

    // Invalid file path name (file is not there).
    char buffer_2[ ] = "C:\\TEST\\file.doc"; 
    char *lpStr2;
    lpStr2 = buffer_2;

    // Return value from "PathFileExists".
    int retval;

    // Search for the presence of a file with a true result.
    retval = PathFileExists(lpStr1);
    if(retval == 1)
    {
        cout << "Search for the file path of : " << lpStr1 << endl;
        cout << "The file requested \"" << lpStr1 << "\" is a valid file" << endl;
        cout << "The return from function is : " << retval << endl;
    }

    else
    {
        cout << "\nThe file requested " << lpStr1 << " is not a valid file" << endl;
        cout << "The return from function is : " << retval << endl;
    }

    // Search for the presence of a file with a false result.
    retval = PathFileExists(lpStr2);

    if(retval == 1)
    {
        cout << "\nThe file requested " << lpStr2 << "is a valid file" << endl;
        cout << "Search for the file path of : " << lpStr2 << endl;
        cout << "The return from function is : " << retval << endl;
    }
    else
    {
        cout << "\nThe file requested \"" << lpStr2 << "\" is not a valid file" << endl;
        cout << "The return from function is : " << retval << endl;
    }
}

OUTPUT
==============
Search for the file path of : C:\TEST\file.txt
The file requested "C:\TEST\file.txt" is a valid file
The return from function is : 1

The file requested "C:\TEST\file.doc" is not a valid file
The return from function is : 0

score 0 · Answer 2 · answered Aug 21 '14 at 17:37

0

Portable solution using Boost.Filesystem:

#include <boost/filesystem.hpp>

//...

boost::filesystem::path dir(directory_path_string);

if (boost::filesystem::is_directory(dir) && boost::filesystem::exists(dir))
{
    // directory exists
}

answered Aug 21 '14 at 17:37

Piotr Skotnicki

46,953
7
118
160

okk yeah, I have installed boost, when I try to #include it reports an error saying there is no such file can you point me to some reference which tells me how to use boost in dev c++? – AnkitSablok Aug 21 '14 at 17:39
@AnkitSablok You need to point Dev-C++ to your boost includes. – Aug 21 '14 at 17:40
2

@AnkitSablok Strange you said you were new to this in your earlier comment, but seem to be able to want to use boost. – PaulMcKenzie Aug 21 '14 at 17:42
Menu bar -> Tools -> Compiler options -> Directories -> C++ Header files: Add path you the main directory of Boost – Piotr Skotnicki Aug 21 '14 at 17:42
I am new to using Boost actually it is my first time :), so thats why I want to do it I checked out in earlier stack overflow posts regarding Boost – AnkitSablok Aug 21 '14 at 17:43
Please remember also to first build your boost libraries – Piotr Skotnicki Aug 21 '14 at 17:45
Piotr S. - how to do that can you tell? – AnkitSablok Aug 21 '14 at 17:46
@AnkitSablok Then you should reword your original question to use `boost` only. Otherwise, the solution you're looking for is a simple call to `GetFileAttributesA` and checking the "directory bit" on the return value. It is the same solution given to you on the page you linked to in your question. – PaulMcKenzie Aug 21 '14 at 17:47
@PaulMcKenzie : Ok, I will change it – AnkitSablok Aug 21 '14 at 17:48
@Ankit For information on how to build boost on your platform, refer to the [documentation](http://www.boost.org/doc/libs/1_56_0/more/getting_started/index.html). For a live example that demonstrates this working code, see [this](http://coliru.stacked-crooked.com/a/9743a25c3728b98c). Remember to link against `boost_filesystem` and `boost_system` which must be built before you can use them. – Aug 21 '14 at 17:53
@AnkitSablok Since C++17 no need to use boost. is part of std now. – qqqqq Feb 17 '22 at 20:07

score 0 · Answer 3 · answered Nov 13 '18 at 12:31

0

Try boost::filesystem:

#include <boost/filesystem.hpp>

if ( !boost::filesystem::exists( "my_directory" ) )
{
  std::cout << "Can't find my directory!" << std::endl;
}

answered Nov 13 '18 at 12:31

Scott Yang

339
3
6

Use #include . It is in C++17. – qqqqq Feb 17 '22 at 20:11

How to check if a string given as input is a valid directory in C++ using Boost Libraries?

3 Answers3