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How to Remove Directories From EnumerateFiles?

So I'm working on a program that will list all the files in a directory. Pretty simple. Basically, when I do this: List<string> dirs = new List<string>(Directory.EnumerateFiles(target));, I don't want it to include the directory and all. Just the file name. When I run my code;
List<string> dirs = new List<string>(Directory.EnumerateFiles(target));
Console.WriteLine($"Folders and files in this directory:\n");
foreach (string i in dirs) {
Console.WriteLine($"> {i}");
}
it gives me the following:
C:\Users\Camden\Desktop\Programming\Visual Studio\C#\DirectoryManager\DirectoryManager\bin\Debug\DirectoryManager.exe
I just want the DirectoryManager.exe part, so I looked it up and I found that you can replace strings inside of strings. Like so: i.Replace(target, "");. However, this isn't doing anything, and it's just running like normal. Why isn't it replacing, and how should I instead do this?

Use methods from the System.IO.Path class.
var fullfile = #"C:\Users\Camden\Desktop\Programming\Visual Studio\C#\DirectoryManager\DirectoryManager\bin\Debug\DirectoryManager.exe";
var fileName = Path.GetFileName(fullfile); // DirectoryManager.exe
var name = Path.GetFileNameWithoutExtension(fullfile); // DirectoryManager

The simplest way is to use the Select IEnumerable extension
(you need to have a using Linq; at the top of your source code file)
List<string> files = new List<string>(Directory.EnumerateFiles(target)
.Select(x => Path.GetFileName(x)));
In this way the sequence of files retrieved by Directory.EnumerateFiles is passed, one by one, to the Select method where each fullfile name (x) is passed to Path.GetFileName to produce a new sequence of just filenames.
This sequence is then returned as a parameter to the List constructor.
And about your question on the Replace method. Remember that the Replace method doesn't change the string that you use to call the method, but returns a new string with the replacement executed. In NET strings are immutable.
So if you want to look at the replacement you need
string justFileName = i.Replace(target, "");

An alternative to using Directory.EnumerateFiles, would be DirectoryInfo.EnumerateFiles. This method returns an IEnumerable<FileInfo>. You can then make use of the FileInfo.Name property of each of the returned objects. Your code would then become:
var files = new DirectoryInfo(target).EnumerateFiles();
Console.WriteLine("Files in this directory:\n");
foreach (FileInfo i in files) {
Console.WriteLine($"> {i.Name}");
}
For just the list of file names:
List<string> fileNames = new DirectoryInfo(target).EnumerateFiles().Select(f => f.Name).ToList();
Alternatively, if you want both files and directories, you can use EnumerateFileSystemInfos. If you need to know if you have a file vs a directory you can query the Attributes property and compare it to the FileAttributes flags enumeration.
var dirsAndFiles = new DirectoryInfo(target).EnumerateFileSystemInfos();
Console.WriteLine("Folders and files in this directory:\n");
foreach (var i in dirsAndFiles) {
var type = (i.Attributes & FileAttributes.Directory) == FileAttributes.Directory ? "Directory" : "File";
Console.WriteLine($"{type} > {i.Name}");
}
The FileSystemInfo.Name property will return either the file's name (in case of a file) or the last directory in the hierarchy (for a directory)--so just the subdirectory name and not the full path ("sub" instead of "c:\sub").

How to search a directory for files that begin with something then get the one that was modified most recently

What I want to do is search/scan a directory for multiple files beginning with something, then get the file that was last modified most recently. For example, I want to search the directory Prefetch for files that begin with "apple", "pear", and "orange". These files may not exist, but if they do, and say there are files that begin with apple and files that begin with pear, out of all of those files, I want to get the one that was modified most recently. The code below allows me do to this but search only 1 thing.
DirectoryInfo prefetch = new DirectoryInfo("c:\\Windows\\Prefetch");
FileInfo[] apple = prefetch.GetFiles("apple*");
if (apple.Length == 0)
// Do something
else
{
double lastused = DateTime.Now.Subtract(
apple.OrderByDescending(x => x.LastWriteTime)
.FirstOrDefault().LastWriteTime).TotalMinutes;
int final = Convert.ToInt32(lastused);
}
Basically, how can I make that code search 'apple', 'pear' etc. instead of just apple? I don't know if you can modify the code above to do that or if you have to change it completely. I've been trying to figure this out for hours and can't do it.

As explained in my comments you can't use DirectoryInfo.GetFiles to return list of FileInfo with so different patterns. Just one pattern is supported.
As others as already shown, you can prepare a list of patterns and then call in a loop the GetFiles on each pattern.
However, I would show you the same approach, but done with just one line of code in Linq.
List<string> patterns = new List<string> { "apple*", "pear*", "orange*" };
DirectoryInfo prefetch = new DirectoryInfo(#"c:\Windows\Prefetch");
var result = patterns.SelectMany(x => prefetch.GetFiles(x))
.OrderByDescending(k => k.LastWriteTime)
.FirstOrDefault();
Now, result is a FileInfo with the most recent update. Of course, if no files matches the three patterns, then result will be null. A check before using that variable is mandatory.

You could create a set of files that match the prefixes then check the date of those files, something like (not tested):
List<string> files=new List<string>();
foreach(var str in prefixes)
files.AddRange(dirInfo.GetFiles(str));
return (from d in (from name in files select File.GetLastAccessTime(name)) orderby d descending).FirstOrDefault();
prefixes is the list of search patterns, and dirInfo is a DirectoryInfo object.

You can iterate over a list
List<string> patterns = new List<string> { "apple*", "pear*", "orange*" };
DirectoryInfo prefetch = new DirectoryInfo("c:\\Windows\\Prefetch");
foreach (var pattern in patterns) {
FileInfo[] files = prefetch.GetFiles(pattern);
var lastAccessed = files.OrderByDescending(x => x.LastAccessTime).FirstOrDefault();
if (lastAccessed != null) {
var minutes = DateTime.Now.Subtract(lastAccessed.LastAccessTime).TotalMinutes;
}
}

Select Files From Folder Depending on Name Convention

I receive a bunch of XML files in a folder.
I want to keep checking for files that have the following naming convention:
sr-{first_id}-{second_id}-matchresults.xml
To parse as soon as I receive one.
For example:
sr-40-24-standings.xml
sr-40-24-results.xml
sr-40-24-j7844-matchresults.xml
I should select that one : sr-40-24-j7844-matchresults.xml
What comes after this that helps me select Files depending on their naming convention from a ASP Web Service?
Dim files As IO.FileInfo() = FolderName.GetFiles("*.xml")

private bool IsValid(string value)
{
string regexString = "^sr-([a-z0-9]+)-([a-z0-9-]+)-matchresults.xml";
return Regex.IsMatch(value, regexString);
}
This method will give you the files with the specified format (sr-{first_id}-{second_id}-matchresults.xml).
Note: your Ids can contain alphanumeric characters also "-" symbol. if you don't want that symbol in id, then code will look like,
string regexString = "^sr-([a-z0-9]+)-([a-z0-9]+)-matchresults.xml";

You can use a regular expression:
var pattern = new Regex(#"^sr-.............$");
And then apply a "filter" on Directoy.GetFiles to retrieve only the files matching this pattern:
var files = Directory.GetFiles("path to files", "*.xml").Where(path => pattern.IsMatch(path)).ToList();

C#: Get the 5 newest (last modified) files from a directory

Is there a way I can store the file location of the 5 last modified files from a directory using Array?
I am currently using the following codes below to get the last file:
DateTime lastHigh = new DateTime(1900,1,1);
string highDir;
foreach (string subdir in Directory.GetDirectories(path)){
DirectoryInfo fi1 = new DirectoryInfo(subdir);
DateTime created = fi1.LastWriteTime;
if (created > lastHigh){
highDir = subdir;
lastHigh = created;
}
}
I'll be using Array to send multiple files to an email address as attachment.
UPDATE
I am currently using the codes below to get the last modified files after 1 minute:
string myDirectory = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.MyPictures),
"Test Folder");
var directory = new DirectoryInfo(myDirectory);
DateTime from_date = DateTime.Now.AddMinutes(-1);
DateTime to_date = DateTime.Now;
var files = directory.GetFiles().Where(file => file.LastWriteTime >= from_date && file.LastWriteTime <= to_date);
I want to store to list of file names coming from files

Here's a general way to do this with LINQ:
Directory.GetFiles(path)
.Select(x => new FileInfo(x))
.OrderByDescending(x => x.LastWriteTime)
.Take(5)
.ToArray()
I suspect this isn't quite what you want, since your code examples seem to be working at different tasks, but in the general case, this would do what the title of your question requests.

It sounds like you want a string array of the full filepaths of all the files in a directory.
Given you already have your FileInfo enumerable, you can do this:
var filenames = files.Select(f => f.FullName).ToArray();
If you wanted just the filenames, replace FullName with Name.

While the answer Paul Phillips provided worked. It's worth to keep in mind that the
FileInfo.LastWriteTime & FileInfo.LastAccessTime do not always work. It depends on how the OS is configured or could be a caching issue.
.NET FileInfo.LastWriteTime & FileInfo.LastAccessTime are wrong
File.GetLastWriteTime seems to be returning 'out of date' value

How to check if filename contains substring in C#

I have a folder with files named
myfileone
myfiletwo
myfilethree
How can I check if file "myfilethree" is present.
I mean is there another method other than IsFileExist() method, i.e like filename contains substring "three"?

Substring:
bool contains = Directory.EnumerateFiles(path).Any(f => f.Contains("three"));
Case-insensitive substring:
bool contains = Directory.EnumerateFiles(path).Any(f => f.IndexOf("three", StringComparison.OrdinalIgnoreCase) > 0);
Case-insensitive comparison:
bool contains = Directory.EnumerateFiles(path).Any(f => String.Equals(f, "myfilethree", StringComparison.OrdinalIgnoreCase));
Get file names matching a wildcard criteria:
IEnumerable<string> files = Directory.EnumerateFiles(path, "three*.*"); // lazy file system lookup
string[] files = Directory.GetFiles(path, "three*.*"); // not lazy

If I understand your question correctly, you could do something like
Directory.GetFiles(directoryPath, "*three*")
or
Directory.GetFiles(directoryPath).Where(f => f.Contains("three"))
Both of these will give you all the names of all files with three in it.

I am not that familiar with IO but maybe this would work ? Requires using System.Linq
System.IO.Directory.GetFiles("PATH").Where(s => s.Contains("three"));
EDIT: Note that this returns array of strings.