What is the syntax for setting multiple file-extensions as searchPattern on Directory.GetFiles()? For example filtering out files with .aspx and .ascx extensions.
// TODO: Set the string 'searchPattern' to only get files with
// the extension '.aspx' and '.ascx'.
var filteredFiles = Directory.GetFiles(path, searchPattern);
Update: LINQ is not an option, it has to be a searchPattern passed into GetFiles, as specified in the question.
I believe there is no "out of the box" solution, that's a limitation of the Directory.GetFiles method.
It's fairly easy to write your own method though, here is an example.
The code could be:
/// <summary> /// Returns file names from given folder that comply to given filters /// </summary> /// <param name="SourceFolder">Folder with files to retrieve</param> /// <param name="Filter">Multiple file filters separated by | character</param> /// <param name="searchOption">File.IO.SearchOption, /// could be AllDirectories or TopDirectoryOnly</param> /// <returns>Array of FileInfo objects that presents collection of file names that /// meet given filter</returns> public string[] getFiles(string SourceFolder, string Filter, System.IO.SearchOption searchOption) { // ArrayList will hold all file names ArrayList alFiles = new ArrayList(); // Create an array of filter string string[] MultipleFilters = Filter.Split('|'); // for each filter find mathing file names foreach (string FileFilter in MultipleFilters) { // add found file names to array list alFiles.AddRange(Directory.GetFiles(SourceFolder, FileFilter, searchOption)); } // returns string array of relevant file names return (string[])alFiles.ToArray(typeof(string)); }
var filteredFiles = Directory
.GetFiles(path, "*.*")
.Where(file => file.ToLower().EndsWith("aspx") || file.ToLower().EndsWith("ascx"))
.ToList();
Edit 2014-07-23
You can do this in .NET 4.5 for a faster enumeration:
var filteredFiles = Directory
.EnumerateFiles(path) //<--- .NET 4.5
.Where(file => file.ToLower().EndsWith("aspx") || file.ToLower().EndsWith("ascx"))
.ToList();
GetFiles can only match a single pattern, but you can use Linq to invoke GetFiles with multiple patterns:
FileInfo[] fi = new string[]{"*.txt","*.doc"}
.SelectMany(i => di.GetFiles(i, SearchOption.AllDirectories))
.ToArray();
See comments section here: http://www.codeproject.com/KB/aspnet/NET_DirectoryInfo.aspx
I like this method, because it is readable and avoids multiple iterations of the directory:
var allowedExtensions = new [] {".doc", ".docx", ".pdf", ".ppt", ".pptx", ".xls", ".xslx"};
var files = Directory
.GetFiles(folder)
.Where(file => allowedExtensions.Any(file.ToLower().EndsWith))
.ToList();
var filteredFiles = Directory
.EnumerateFiles(path, "*.*") // .NET4 better than `GetFiles`
.Where(
// ignorecase faster than tolower...
file => file.ToLower().EndsWith("aspx")
|| file.EndsWith("ascx", StringComparison.OrdinalIgnoreCase))
.ToList();
- Don't forget the new .NET4
Directory.EnumerateFilesfor a performance boost (What is the difference between Directory.EnumerateFiles vs Directory.GetFiles?) - "IgnoreCase" should be faster than "ToLower"
Or, it may be faster to split and merge your globs (at least it looks cleaner):
"*.ext1;*.ext2".Split(';')
.SelectMany(g => Directory.EnumerateFiles(path, g))
.ToList();
I fear you will have to do somthing like this, I mutated the regex from here.
var searchPattern = new Regex(
@"$(?<=\.(aspx|ascx))",
RegexOptions.IgnoreCase);
var files = Directory.EnumerateFiles(path)
.Where(f => searchPattern.IsMatch(f))
.ToList();
I would use the following:
var ext = new string[] { ".ASPX", ".ASCX" };
FileInfo[] collection = (from fi in new DirectoryInfo(path).GetFiles()
where ext.Contains(fi.Extension.ToUpper())
select fi)
.ToArray();
EDIT: corrected due mismatch between Directory and DirectoryInfo
A more efficient way of getting files with the extensions ".aspx" and ".ascx" that avoids querying the file system several times and avoids returning a lot of undesired files, is to pre-filter the files by using an approximate search pattern and to refine the result afterwards:
var filteredFiles = Directory.GetFiles(path, "*.as?x")
.Select(f => f.ToLowerInvariant())
.Where(f => f.EndsWith("px") || f.EndsWith("cx"))
.ToList();
The easy-to-remember, lazy and perhaps imperfect solution:
Directory.GetFiles(dir, "*.dll").Union(Directory.GetFiles(dir, "*.exe"))
I would try to specify something like
var searchPattern = "as?x";
it should work.
/// <summary>
/// Returns the names of files in a specified directories that match the specified patterns using LINQ
/// </summary>
/// <param name="srcDirs">The directories to seach</param>
/// <param name="searchPatterns">the list of search patterns</param>
/// <param name="searchOption"></param>
/// <returns>The list of files that match the specified pattern</returns>
public static string[] GetFilesUsingLINQ(string[] srcDirs,
string[] searchPatterns,
SearchOption searchOption = SearchOption.AllDirectories)
{
var r = from dir in srcDirs
from searchPattern in searchPatterns
from f in Directory.GetFiles(dir, searchPattern, searchOption)
select f;
return r.ToArray();
}
public static bool CheckFiles(string pathA, string pathB)
{
string[] extantionFormat = new string[] { ".war", ".pkg" };
return CheckFiles(pathA, pathB, extantionFormat);
}
public static bool CheckFiles(string pathA, string pathB, string[] extantionFormat)
{
System.IO.DirectoryInfo dir1 = new System.IO.DirectoryInfo(pathA);
System.IO.DirectoryInfo dir2 = new System.IO.DirectoryInfo(pathB);
// Take a snapshot of the file system. list1/2 will contain only WAR or PKG
// files
// fileInfosA will contain all of files under path directories
FileInfo[] fileInfosA = dir1.GetFiles("*.*",
System.IO.SearchOption.AllDirectories);
// list will contain all of files that have ..extantion[]
// Run on all extantion in extantion array and compare them by lower case to
// the file item extantion ...
List<System.IO.FileInfo> list1 = (from extItem in extantionFormat
from fileItem in fileInfosA
where extItem.ToLower().Equals
(fileItem.Extension.ToLower())
select fileItem).ToList();
// Take a snapshot of the file system. list1/2 will contain only WAR or
// PKG files
// fileInfosA will contain all of files under path directories
FileInfo[] fileInfosB = dir2.GetFiles("*.*",
System.IO.SearchOption.AllDirectories);
// list will contain all of files that have ..extantion[]
// Run on all extantion in extantion array and compare them by lower case to
// the file item extantion ...
List<System.IO.FileInfo> list2 = (from extItem in extantionFormat
from fileItem in fileInfosB
where extItem.ToLower().Equals
(fileItem.Extension.ToLower())
select fileItem).ToList();
FileCompare myFileCompare = new FileCompare();
// This query determines whether the two folders contain
// identical file lists, based on the custom file comparer
// that is defined in the FileCompare class.
return list1.SequenceEqual(list2, myFileCompare);
}
Instead of the EndsWith function, I would choose to use the Path.GetExtension() method instead. Here is the full example:
var filteredFiles = Directory.EnumerateFiles( path )
.Where(
file => Path.GetExtension(file).Equals( ".aspx", StringComparison.OrdinalIgnoreCase ) ||
Path.GetExtension(file).Equals( ".ascx", StringComparison.OrdinalIgnoreCase ) );
or:
var filteredFiles = Directory.EnumerateFiles(path)
.Where(
file => string.Equals( Path.GetExtension(file), ".aspx", StringComparison.OrdinalIgnoreCase ) ||
string.Equals( Path.GetExtension(file), ".ascx", StringComparison.OrdinalIgnoreCase ) );
(Use StringComparison.OrdinalIgnoreCase if you care about performance: MSDN string comparisons)
look like this demo:
void Main()
{
foreach(var f in GetFilesToProcess("c:\\", new[] {".xml", ".txt"}))
Debug.WriteLine(f);
}
private static IEnumerable<string> GetFilesToProcess(string path, IEnumerable<string> extensions)
{
return Directory.GetFiles(path, "*.*")
.Where(f => extensions.Contains(Path.GetExtension(f).ToLower()));
}
var filtered = Directory.GetFiles(path)
.Where(file => file.EndsWith("aspx", StringComparison.InvariantCultureIgnoreCase) || file.EndsWith("ascx", StringComparison.InvariantCultureIgnoreCase))
.ToList();
@Daniel B, thanks for the suggestion to write my own version of this function. It has the same behavior as Directory.GetFiles, but supports regex filtering.
string[] FindFiles(FolderBrowserDialog dialog, string pattern)
{
Regex regex = new Regex(pattern);
List<string> files = new List<string>();
var files=Directory.GetFiles(dialog.SelectedPath);
for(int i = 0; i < files.Count(); i++)
{
bool found = regex.IsMatch(files[i]);
if(found)
{
files.Add(files[i]);
}
}
return files.ToArray();
}
I found it useful, so I thought I'd share.
c# version of @qfactor77's answer. This is the best way without LINQ .
string[] wildcards= {"*.mp4", "*.jpg"};
ReadOnlyCollection<string> filePathCollection = FileSystem.GetFiles(dirPath, Microsoft.VisualBasic.FileIO.SearchOption.SearchAllSubDirectories, wildcards);
string[] filePath=new string[filePathCollection.Count];
filePathCollection.CopyTo(filePath,0);
now return filePath string array. In the beginning you need
using Microsoft.VisualBasic.FileIO;
using System.Collections.ObjectModel;
also you need to add reference to Microsoft.VisualBasic
I did a simple way for seach as many extensions as you need, and with no ToLower(), RegEx, foreach...
List<String> myExtensions = new List<String>() { ".aspx", ".ascx", ".cs" }; // You can add as many extensions as you want.
DirectoryInfo myFolder = new DirectoryInfo(@"C:\FolderFoo");
SearchOption option = SearchOption.TopDirectoryOnly; // Use SearchOption.AllDirectories for seach in all subfolders.
List<FileInfo> myFiles = myFolder.EnumerateFiles("*.*", option)
.Where(file => myExtensions
.Any(e => String.Compare(file.Extension, e, CultureInfo.CurrentCulture, CompareOptions.IgnoreCase) == 0))
.ToList();
Working on .Net Standard 2.0.
Just would like to say that if you use FileIO.FileSystem.GetFiles instead of Directory.GetFiles, it will allow an array of wildcards.
For example:
Dim wildcards As String() = {"*.html", "*.zip"}
Dim ListFiles As List(Of String) = FileIO.FileSystem.GetFiles(directoryyouneed, FileIO.SearchOption.SearchTopLevelOnly, wildcards).ToList
来源：https://stackoverflow.com/questions/7039580/multiple-file-extensions-searchpattern-for-system-io-directory-getfiles