asked on

C# - File IO question

I need to loop through all folders under a directory I have in the code and for each folder delete all files that have the extension "PDF" that are not the latest file date file. So I need to somehow delete all but one based on the file date keeping the latest file. Any idea how I do that?

William Domenz

List<string> AllPdfs = new List<string>( Directory.GetFiles( "Your Directory" , "*.PDF" , SearchOption.AllDirectories ) );
            foreach ( string PDF in AllPdfs )
            {
                FileInfo FI = new FileInfo( PDF );
                if ( FI.LastWriteTime > "YOUR DATE TIME HERE!" )
                    File.Delete( PDF );
            }

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sbornstein2

ASKER

actually sorry there is one more thing I just realized. I also need to look at the start of the file name and group it by invoice date. Sorry so for example let's say I have four files in the directory for march and april end but I need the latest of each invoice date file which is the start of the filename before the first underscore:

3312009_01400071_179505084.pdf Date 4/7/09 11:00AM
3312009_01400071_179505085.pdf Date 4/7/09 11:42AM

4302009_01400071_179505084.pdf Date 4/7/09 11:15AM
4302009_01400071_179505085.pdf Date 4/7/09 11:20AM

I would want to delete the 1st file for each set of these and only be left with:
3312009_01400071_179505085.pdf Date 4/7/09 11:42AM
4302009_01400071_179505085.pdf Date 4/7/09 11:20AM

sbornstein2

ASKER

something on the lines of I can loop through the folders such as:

public void CleanupMacOldPDFs()
{
string PdfFolder = "\\\\fileserver";
string[] PDFDir = Directory.GetDirectories(@PdfFolder);

foreach (string FolderName in PDFDir)
{

}

}

William Domenz

You are only interested in the files right? Does it matter what dir they are in?

sbornstein2

ASKER

also i dont want to pass it a datetime I just want to look at the dates and only delete everything but the new one.

sbornstein2

ASKER

i need to cleanup each directory where we only have one invoice date PDF file and only the latest file dated file.

sbornstein2

ASKER

but the directories are all under one root directory so I would provide the root directory and then loop through each folder and cleanup the old files I don't need.

William Domenz

This oughta to get what you are after...

     List<string> PDFDirs = new List<string>( Directory.GetDirectories( "Your Root Directory" , "*" , SearchOption.AllDirectories ) );
            foreach ( string DIR in PDFDirs )
            {
                List<string> AllPdfs = new List<string>( Directory.GetFiles( DIR , "*.PDF" , SearchOption.AllDirectories ) );
                foreach ( string PDF in AllPdfs )
                {
                    FileInfo FI = new FileInfo( PDF );
                    if ( FI.LastWriteTime > "YOUR DATE TIME HERE!" )
                        File.Delete( PDF );
                }
            }

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ASKER CERTIFIED SOLUTION

kaufmed

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sbornstein2

ASKER

going to test it here. Doesn't like this line though,

list.Add(group, new List<System.IO.FileInfo>() { file });

trying to figure that out the { file } missing paren or something.

kaufmed

Just as well, you can change the line from

list.Add(group, new List<System.IO.FileInfo>() { file });

to

list.Add(group, new List<System.IO.FileInfo>());
list[group].Add(file);

sbornstein2

ASKER

this was perfect thanks so much.