Develop Reference

How to filter files with date from a folder in C#

I have c# code to get the pdf files from a folder.
string[] pdfFiles = Directory.GetFiles(EnvSettingsTools.FilePath.ToString(), "*.pdf")
.Select(path => Path.GetFileNameWithoutExtension(path))
.ToArray();
How can i use this code to get the files by filter by date. The file format will be
LondoPage 20160301.pdf
I need to filter the files with the date in the end of filename. i.e, if i pass date '20160301' the mentioned file should select.

Try
var date = "20160301";
string[] pdfFiles = Directory.GetFiles(EnvSettingsTools.FilePath.ToString(), "*.pdf")
.Select(path => Path.GetFileNameWithoutExtension(path))
.Where(f => f.EndsWith(date))
.ToArray();

This will get files whose name ends with date you pass for filter:
var date = "20160301";
string[] pdfFiles = Directory.GetFiles(EnvSettingsTools.FilePath.ToString(), "*.pdf")
.Select(Path.GetFileNameWithoutExtension)
.Where(f => f.EndsWith(date))
.ToArray();

I did not quite understand your desired outcome but I will do an educated guess that you need to be able to order or filter the folder content. That can be achieved in more than one way. I will propose a solution to your problem
if (!Directory.Exists(pathToFiles)) return;
DirectoryInfo di = new DirectoryInfo(pathToFiles);
FileSystemInfo[] files = di.GetFileSystemInfos();
var orderedFiles = files.OrderBy(f => f.CreationTime);
var filteredFileByDate = orderedFiles.Where(f => f.FullName.ToLowerInvariant().Split('/').Last().Contains("filterText"));
With the ordered files you will receive all files ordered by a particular property, in this case I have chosen the creation date.
With the filtered file you will receive a collection of one or more files that mach your criteria. The more precise is your criteria the less results you get.
Hope that it helps ;)

GetDirectories - Find the directory that does not match the pattern

I have 140 directories that I'm trying to process. According to my tests there are 139 directories that match my file pattern (*abc.txt).
I'm trying to find the 1 directory to verify that in fact it does not have a *abc.txt in it.
How can I do this?
The following code gives me the 140 directories number:
var directoryCount = from subdirectory in Directory.GetDirectories(paramStartFilePath, "*", SearchOption.AllDirectories)
where Directory.GetDirectories(subdirectory).Length == 0
select subdirectory;
I'm gathering the files based off the pattern like this:
dirInfoFiles= new DirectoryInfo(startFilePath);
IEnumerable<FileInfo> listFiles = dirInfoFiles.EnumerateFiles("*abc.txt, System.IO.SearchOption.AllDirectories);
How can I find the the one directory that doesn't contain my .txt file?

There is always the running the tank through the village approach: just enumerate *.* and then exclude the patterns that don't match.

If you want all directories that does not contain at least one txt-file which name ends with "abc":
IEnumerable<DirectoryInfo> matchingDirs = dirInfoFiles.EnumerateDirectories("*.*", System.IO.SearchOption.AllDirectories)
.Where(d => !d.EnumerateFiles().Any(f => f.Extension.ToUpper() == ".TXT"
&& f.Name.EndsWith("abc", StringComparison.OrdinalIgnoreCase)));
or the same in other words, possibly more readable:
IEnumerable<DirectoryInfo> matchingDirs = dirInfoFiles
.EnumerateDirectories("*.*", System.IO.SearchOption.AllDirectories)
.Where(d => !d.EnumerateFiles("*abc.txt").Any());

Here is my take. It returns the first item (or null) that contains a file ending with the text you are looking for and is case insensitive. You could remove the lambdas to make it more readable.
var directory = Directory.GetDirectories((paramStartFilePath, "*", SearchOption.AllDirectories)
.FirstOrDefault(x => new DirectoryInfo(x).EnumerateFiles().Any(f => !f.Name.EndsWith("abc.txt",true,CultureInfo.CurrentCulture)));

How to exclude folders when using Directory.GetDirectories

I want to return a list of all the subdirectories in the 'SomeFolder' directory excluding the 'Admin' and 'Templates' directories.
I have the following folder structure (simplified):
C:\inetpub\wwwroot\MyWebsite\SomeFolder\RandomString
C:\inetpub\wwwroot\MyWebsite\SomeFolder\RandomString
C:\inetpub\wwwroot\MyWebsite\SomeFolder\RandomString
C:\inetpub\wwwroot\MyWebsite\SomeFolder\Admin
C:\inetpub\wwwroot\MyWebsite\SomeFolder\Templates
'SomeFolder' can contain a varying number a 'RandomString' folders (anywhere from ~10 to ~100).
Here is what I have tried:
var dirs = Directory.GetDirectories(Server.MapPath(".."))
.Where(s => !s.EndsWith("Admin") || !s.EndsWith("Templates"));
foreach (string dir in dirs)
{
lit.Text += Environment.NewLine + dir;
}
This returns the full list of folders (shown above) without 'Admin' and 'Templates' filtered out.
Interestingly, if I change the LINQ .Where clause to include, instead of exclude, 'Admin' and 'Templates' it works, meaning it returns just the paths for 'Admin' and 'Templates'.
.Where(s => s.EndsWith("Admin") || s.EndsWith("Templates"));
If LINQ is not the solution, is there any way to use the GetDirectories SearchPattern to filter out directories?

You can do something like:
//list your excluded dirs
private List<string> _excludedDirectories= new List<string>() { "Admin", "Templates" };
//method to check
static bool isExcluded(List<string> exludedDirList, string target)
{
return exludedDirList.Any(d => new DirectoryInfo(target).Name.Equals(d));
}
//then use this
var filteredDirs = Directory.GetDirectories(path).Where(d => !isExcluded(_excludedDirectories, d));

the opposite of (A || B) is (!A && !B), so in your code it should be &&, not ||...

Creating a list of docs that contains same name

I'm creating a tool that is supposed to concatenate docs that contain the same name.
example: C_BA_20000_1.pdf and C_BA_20000_2.pdf
These files should be grouped in one list.
That tool runs on a directory lets say
//directory of pdf files
DirectoryInfo dirInfo = new DirectoryInfo(#"C:\Users\derp\Desktop");
FileInfo[] fileInfos = dirInfo.GetFiles("*.pdf");
foreach (FileInfo info in fileInfos)
I want to create an ArrayList that contains filenames of the same name
ArrayList list = new ArrayList();
list.Add(info.FullName);
and then have a list that contains all the ArrayLists of similar docs.
List<ArrayList> bigList = new List<ArrayList>();
So my question, how can I group files that contains same name and put them in the same list.
EDIT:
Files have the same pattern in their names AB_CDEFG_i
where i is a number and can be from 1-n. Files with the same name should have only different number at the end.
AB_CDEFG_1
AB_CDEFG_2
HI_JKLM_1
Output should be:
List 1: AB_CDEFG_1 and AB_CDEFG_2
List 2: HI_JKLM_1

Create method which extracts 'same' part of file name. E.g.
public string GetRawName(string fileName)
{
int index = fileName.LastIndexOf("_");
return fileName.Substring(0, index);
}
And use this method for grouping:
var bigList = Directory.EnumerateFiles(#"C:\Users\derp\Desktop", "*.pdf")
.GroupBy(file => GetRawName(file))
.Select(g => g.ToList())
.ToList();
This will return List<List<string>> (without ArrayList).
UPDATE Here is regular expression, which will work with all kind of files, whether they have number at the end, or not
public string GetRawName(string file)
{
string name = Path.GetFileNameWithoutExtension(file);
return Regex.Replace(name, #"(_\d+)?$", "")
}
Grouping:
var bigList = Directory.EnumerateFiles(#"C:\Users\derp\Desktop", "*.pdf")
.GroupBy(GetRawName)
.Select(g => g.ToList())
.ToList();

It sounds like the difficulty is in deciding which files are the same.
static string KeyFromFileName(string file)
{
// Convert from "C_BA_20000_2" to "C_BA_20000"
return file.Substring(0, file.LastIndexOf("_"));
// Note: This assumes there is an _ in the filename.
}
Then you can use this LINQ to build a list of fileSets.
using System.Linq; // Near top of file
var files = Directory.GetFiles(#"C:\Users\derp\Desktop", "*.pdf")
var fileSets = files
.Select(file => file.FullName)
.GroupBy(KeyFromFileName)
.Select(g => new {g.Key, Files = g.ToList()}
.ToList();

Aside from the fact that your question doesnt identify what "same name" means. This is a typical solution.
fileInfos.GroupBy ( f => f.FullName )
.Select( grp => grp.ToList() ).ToList();

This will get you a list of lists... also won't throw an exception if a file doesn't contain the underscore, etc.
private string GetKey(FileInfo fi)
{
var index = fi.Name.LastIndexOf('_');
return index == -1 ? Path.GetFileNameWithoutExtension(fi.Name)
: fi.Name.Substring(0, index);
}
var bigList = fileInfos.GroupBy(GetKey)
.Select(x => x.ToList())
.ToList();

Using the linq search option in enumerate files

Quick one here. I am trying to EnumerateFiles in a C# application and I want to find all the files in a directory that do not match a given pattern. So I would have something like this:
var files = Directory.EnumerateFiles("MY_DIR_PATH", "NOT_MY_FILE_NAME");
Can someone help me out with the not part?

I don't think you can use that overload of EnumerateFiles for this, but you can use linq:
Directory.EnumerateFiles("MY_DIR_PATH").Where(s => s != "NOT_MY_FILE_NAME");
or in query syntax:
var files = from f in Directory.EnumerateFiles("MY_DIR_PATH")
where f != "NOT_MY_FILE_NAME"
select f;

You can do something like that:
var files = Directory.EnumerateFiles("MY_DIR_PATH")
.Where(fileName => fileName != "MY_FILE_NAME");

How about
var files = Directory.GetFiles("MY_DIR_PATH")
.Where(f => !f.Contains("NOT_MY_FILE_NAME"));