Question

Is there a way to get all the files (last modified on a specific date), and save them into a new folder (with the name of the specific date).

Example files:

Inside C:/

Image File     Date Modified

Image001.jpg   11/12/2012
Image002.jpg   11/12/2012
Image003.jpg   11/13/2012
Image004.jpg   11/12/2012

Output should be:

C:/20121112/

Image001.jpg
Image002.jpg
Image004.jpg  

C:/20121113

Image003.jpg

I am currently using the syntax below:

var mydirectory = new DirectoryInfo("C:/");
DateTime from_date = DateTime.Now.AddDays(-1);
DateTime to_date = DateTime.Now;
var files = directory.GetFiles()
  .Where(file=>file.LastWriteTime >= from_date && file.LastWriteTime <= to_date);

But I don’t how save to save var files to another folder name.

Answer 1

Perhaps:

var files = Directory.EnumerateFiles(path, "*.jpg", SearchOption.TopDirectoryOnly)
                     .Select(fn => new FileInfo(fn));
var fileDateGroups = files.GroupBy(fi => fi.LastWriteTime.Date);
foreach (var dateGroup in fileDateGroups)
{
    string dir = Path.Combine(@"C:\", dateGroup.Key.ToString("yyyyMMdd"));
    Directory.CreateDirectory(dir);
    foreach (var file in dateGroup)
    {
        string newPath = Path.Combine(dir, file.Name);
        File.Copy(file.FullName, newPath, true);
    }
}

Edit: If you want to search for multiple file extensions you need to filter them manually:

var allowed = new[]{ ".png", ".jpg" };
var files = Directory.EnumerateFiles(path, "*.*", SearchOption.TopDirectoryOnly)
                     .Where(fn => allowed.Contains(Path.GetExtension(fn)))
                     .Select(fn => new FileInfo(fn));