如何在C ++中从给定目录中删除所有文本文件

Question

I'm trying to figure out how to delete all text files from a given directory. I'm using Visual c++ 2010 express, using winapi. I'm aware of how to delete a file if you know the exact name of that file, but I would like to delete all text files within that directory. This is my latest attempt:

void deleteFiles( WCHAR file[] )
{
  // WCHAR file[] is actually the directory path. i.e C:\Users\TheUser\Desktop\Folder\

  // Convert from WCHAR to char for future functions
  char filePath[ MAX_PATH ];
  int i;
  for( int i = 0; file[ i ] != '\0'; i++ )
  {
    // Cycle through each character from the array and place it in the new array
    filePath[ i ] = file[ i ];
  }
  // Place the null character at the end
  filePath[ i ] = '\0';

  // Generate WIN32_FIND_DATA struct and FindFirstFile()
  WIN32_FIND_DATA fileData;
  FindFirstFile( file, &fileData );

  // Display the filename
  MessageBox( NULL, fileData.cFileName, L"Check", MB_OK );
}

The message box only displays the folder that was selected, not the filename. Why is that happening?

Answer 1

A subtle problem is that you have two variables with the same name and different scope: One defined outside the loop and which is uninitialized; The other declared inside the loop.

The variables I'm referring to are the ones named i .

Because the one defined outside the loop is uninitialized, when you use it as an index to terminate the path its value is indeterminate and you have undefined behavior.

Answer 2

First of all, converting WCHARs to char is not a good idea, since the paths can contain Unicode characters and you'll get errors.

The second thing is that for FindFirstFile to work, you need to add wildcards, eg C:\\Path\\* .

Here's an example on MSDN which enumerates files in a directory: http://msdn.microsoft.com/en-us/library/windows/desktop/aa365200%28v=vs.85%29.aspx