Directory.GetFileSystemEntries Method

Definition

Returns the names of all files and subdirectories that meet specified criteria.

Overloads

GetFileSystemEntries(String)

Returns the names of all files and subdirectories in a specified path.

GetFileSystemEntries(String, String)

Returns an array of file names and directory names that match a search pattern in a specified path.

GetFileSystemEntries(String, String, EnumerationOptions)

Returns an array of file names and directory names that match a search pattern and enumeration options in a specified path.

GetFileSystemEntries(String, String, SearchOption)

Returns an array of all the file names and directory names that match a search pattern in a specified path, and optionally searches subdirectories.

GetFileSystemEntries(String)

Source:
Directory.cs
Source:
Directory.cs
Source:
Directory.cs

Returns the names of all files and subdirectories in a specified path.

C#
public static string[] GetFileSystemEntries(string path);

Parameters

path
String

The relative or absolute path to the directory to search. This string is not case-sensitive.

Returns

String[]

An array of the names of files and subdirectories in the specified directory, or an empty array if no files or subdirectories are found.

Exceptions

The caller does not have the required permission.

.NET Framework and .NET Core versions older than 2.1: path is a zero-length string, contains only white space, or contains one or more invalid characters. You can query for invalid characters with GetInvalidPathChars().

path is null.

The specified path, file name, or both exceed the system-defined maximum length.

path is a file name.

The specified path is invalid (for example, it is on an unmapped drive).

Examples

The following example uses the GetFileSystemEntries method to fill an array of strings with the names of all files and subdirectories in a user-specified location and prints each string in the array to the console. The example is configured to catch all errors common to this method.

C#
using System;

namespace GetFileSystemEntries
{
    class Class1
    {
        static void Main(string[] args)
        {
            Class1 snippets = new Class1();

            string path = System.IO.Directory.GetCurrentDirectory();
            string filter = "*.exe";

            snippets.PrintFileSystemEntries(path);
            snippets.PrintFileSystemEntries(path, filter);		
            snippets.GetLogicalDrives();
            snippets.GetParent(path);
            snippets.Move("C:\\proof", "C:\\Temp");
        }

        void PrintFileSystemEntries(string path)
        {
            
            try
            {
                // Obtain the file system entries in the directory path.
                string[] directoryEntries =
                    System.IO.Directory.GetFileSystemEntries(path);

                foreach (string str in directoryEntries)
                {
                    System.Console.WriteLine(str);
                }
            }
            catch (ArgumentNullException)
            {
                System.Console.WriteLine("Path is a null reference.");
            }
            catch (System.Security.SecurityException)
            {
                System.Console.WriteLine("The caller does not have the " +
                    "required permission.");
            }
            catch (ArgumentException)
            {
                System.Console.WriteLine("Path is an empty string, " +
                    "contains only white spaces, " +
                    "or contains invalid characters.");
            }
            catch (System.IO.DirectoryNotFoundException)
            {
                System.Console.WriteLine("The path encapsulated in the " +
                    "Directory object does not exist.");
            }
        }
        void PrintFileSystemEntries(string path, string pattern)
        {
            try
            {
                // Obtain the file system entries in the directory
                // path that match the pattern.
                string[] directoryEntries =
                    System.IO.Directory.GetFileSystemEntries(path, pattern);

                foreach (string str in directoryEntries)
                {
                    System.Console.WriteLine(str);
                }
            }
            catch (ArgumentNullException)
            {
                System.Console.WriteLine("Path is a null reference.");
            }
            catch (System.Security.SecurityException)
            {
                System.Console.WriteLine("The caller does not have the " +
                    "required permission.");
            }
            catch (ArgumentException)
            {
                System.Console.WriteLine("Path is an empty string, " +
                    "contains only white spaces, " +
                    "or contains invalid characters.");
            }
            catch (System.IO.DirectoryNotFoundException)
            {
                System.Console.WriteLine("The path encapsulated in the " +
                    "Directory object does not exist.");
            }
        }

        // Print out all logical drives on the system.
        void GetLogicalDrives()
        {
            try
            {
                string[] drives = System.IO.Directory.GetLogicalDrives();

                foreach (string str in drives)
                {
                    System.Console.WriteLine(str);
                }
            }
            catch (System.IO.IOException)
            {
                System.Console.WriteLine("An I/O error occurs.");
            }
            catch (System.Security.SecurityException)
            {
                System.Console.WriteLine("The caller does not have the " +
                    "required permission.");
            }
        }
        void GetParent(string path)
        {
            try
            {
                System.IO.DirectoryInfo directoryInfo =
                    System.IO.Directory.GetParent(path);

                System.Console.WriteLine(directoryInfo.FullName);
            }
            catch (ArgumentNullException)
            {
                System.Console.WriteLine("Path is a null reference.");
            }
            catch (ArgumentException)
            {
                System.Console.WriteLine("Path is an empty string, " +
                    "contains only white spaces, or " +
                    "contains invalid characters.");
            }
        }
        void Move(string sourcePath, string destinationPath)
        {
            try
            {
                System.IO.Directory.Move(sourcePath, destinationPath);
                System.Console.WriteLine("The directory move is complete.");
            }
            catch (ArgumentNullException)
            {
                System.Console.WriteLine("Path is a null reference.");
            }
            catch (System.Security.SecurityException)
            {
                System.Console.WriteLine("The caller does not have the " +
                    "required permission.");
            }
            catch (ArgumentException)
            {
                System.Console.WriteLine("Path is an empty string, " +
                    "contains only white spaces, " +
                    "or contains invalid characters.");	
            }
            catch (System.IO.IOException)
            {
                System.Console.WriteLine("An attempt was made to move a " +
                    "directory to a different " +
                    "volume, or destDirName " +
                    "already exists.");
            }
        }
    }
}

Remarks

The order of the returned file and directory names is not guaranteed; use the Sort method if a specific sort order is required.

The EnumerateFileSystemEntries and GetFileSystemEntries methods differ as follows: When you use EnumerateFileSystemEntries, you can start enumerating the collection of entries before the whole collection is returned; when you use GetFileSystemEntries, you must wait for the whole array of entries to be returned before you can access the array. Therefore, when you are working with many files and directories, EnumerateFileSystemEntries can be more efficient.

This method is identical to GetFileSystemEntries with the asterisk (*) specified as the search pattern.

The path parameter is permitted to specify relative or absolute path information. Relative path information is interpreted as relative to the current working directory. To obtain the current working directory, see GetCurrentDirectory.

The case-sensitivity of the path parameter corresponds to that of the file system on which the code is running. For example, it's case-insensitive on NTFS (the default Windows file system) and case-sensitive on Linux file systems.

For a list of common I/O tasks, see Common I/O Tasks.

See also

Applies to

.NET 10 and other versions
Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0

GetFileSystemEntries(String, String)

Source:
Directory.cs
Source:
Directory.cs
Source:
Directory.cs

Returns an array of file names and directory names that match a search pattern in a specified path.

C#
public static string[] GetFileSystemEntries(string path, string searchPattern);

Parameters

path
String

The relative or absolute path to the directory to search. This string is not case-sensitive.

searchPattern
String

The search string to match against the names of files and directories in path. This parameter can contain a combination of valid literal path and wildcard (* and ?) characters, but it doesn't support regular expressions.

Returns

String[]

An array of file names and directory names that match the specified search criteria, or an empty array if no files or directories are found.

Exceptions

The caller does not have the required permission.

.NET Framework and .NET Core versions older than 2.1: path is a zero-length string, contains only white space, or contains one or more invalid characters. You can query for invalid characters with the GetInvalidPathChars() method.

-or-

searchPattern does not contain a valid pattern.

path or searchPattern is null.

The specified path, file name, or both exceed the system-defined maximum length.

path is a file name.

The specified path is invalid (for example, it is on an unmapped drive).

Examples

The following example uses the GetFileSystemEntries method to fill an array of strings with the names of all files matching a user-specified filter in a specific location and prints each string in the array to the console. The example is configured to catch all errors common to this method.

C#
using System;

namespace GetFileSystemEntries
{
    class Class1
    {
        static void Main(string[] args)
        {
            Class1 snippets = new Class1();

            string path = System.IO.Directory.GetCurrentDirectory();
            string filter = "*.exe";

            snippets.PrintFileSystemEntries(path);
            snippets.PrintFileSystemEntries(path, filter);		
            snippets.GetLogicalDrives();
            snippets.GetParent(path);
            snippets.Move("C:\\proof", "C:\\Temp");
        }

        void PrintFileSystemEntries(string path)
        {
            
            try
            {
                // Obtain the file system entries in the directory path.
                string[] directoryEntries =
                    System.IO.Directory.GetFileSystemEntries(path);

                foreach (string str in directoryEntries)
                {
                    System.Console.WriteLine(str);
                }
            }
            catch (ArgumentNullException)
            {
                System.Console.WriteLine("Path is a null reference.");
            }
            catch (System.Security.SecurityException)
            {
                System.Console.WriteLine("The caller does not have the " +
                    "required permission.");
            }
            catch (ArgumentException)
            {
                System.Console.WriteLine("Path is an empty string, " +
                    "contains only white spaces, " +
                    "or contains invalid characters.");
            }
            catch (System.IO.DirectoryNotFoundException)
            {
                System.Console.WriteLine("The path encapsulated in the " +
                    "Directory object does not exist.");
            }
        }
        void PrintFileSystemEntries(string path, string pattern)
        {
            try
            {
                // Obtain the file system entries in the directory
                // path that match the pattern.
                string[] directoryEntries =
                    System.IO.Directory.GetFileSystemEntries(path, pattern);

                foreach (string str in directoryEntries)
                {
                    System.Console.WriteLine(str);
                }
            }
            catch (ArgumentNullException)
            {
                System.Console.WriteLine("Path is a null reference.");
            }
            catch (System.Security.SecurityException)
            {
                System.Console.WriteLine("The caller does not have the " +
                    "required permission.");
            }
            catch (ArgumentException)
            {
                System.Console.WriteLine("Path is an empty string, " +
                    "contains only white spaces, " +
                    "or contains invalid characters.");
            }
            catch (System.IO.DirectoryNotFoundException)
            {
                System.Console.WriteLine("The path encapsulated in the " +
                    "Directory object does not exist.");
            }
        }

        // Print out all logical drives on the system.
        void GetLogicalDrives()
        {
            try
            {
                string[] drives = System.IO.Directory.GetLogicalDrives();

                foreach (string str in drives)
                {
                    System.Console.WriteLine(str);
                }
            }
            catch (System.IO.IOException)
            {
                System.Console.WriteLine("An I/O error occurs.");
            }
            catch (System.Security.SecurityException)
            {
                System.Console.WriteLine("The caller does not have the " +
                    "required permission.");
            }
        }
        void GetParent(string path)
        {
            try
            {
                System.IO.DirectoryInfo directoryInfo =
                    System.IO.Directory.GetParent(path);

                System.Console.WriteLine(directoryInfo.FullName);
            }
            catch (ArgumentNullException)
            {
                System.Console.WriteLine("Path is a null reference.");
            }
            catch (ArgumentException)
            {
                System.Console.WriteLine("Path is an empty string, " +
                    "contains only white spaces, or " +
                    "contains invalid characters.");
            }
        }
        void Move(string sourcePath, string destinationPath)
        {
            try
            {
                System.IO.Directory.Move(sourcePath, destinationPath);
                System.Console.WriteLine("The directory move is complete.");
            }
            catch (ArgumentNullException)
            {
                System.Console.WriteLine("Path is a null reference.");
            }
            catch (System.Security.SecurityException)
            {
                System.Console.WriteLine("The caller does not have the " +
                    "required permission.");
            }
            catch (ArgumentException)
            {
                System.Console.WriteLine("Path is an empty string, " +
                    "contains only white spaces, " +
                    "or contains invalid characters.");	
            }
            catch (System.IO.IOException)
            {
                System.Console.WriteLine("An attempt was made to move a " +
                    "directory to a different " +
                    "volume, or destDirName " +
                    "already exists.");
            }
        }
    }
}

Remarks

The order of the returned file and directory names is not guaranteed; use the Sort method if a specific sort order is required.

searchPattern can be a combination of literal and wildcard characters, but it doesn't support regular expressions. The following wildcard specifiers are permitted in searchPattern.

Wildcard specifier Matches
* (asterisk) Zero or more characters in that position.
? (question mark) Exactly one character in that position.

Characters other than the wildcard are literal characters. For example, the searchPattern string "*t" searches for all names in path ending with the letter "t". The searchPattern string "s*" searches for all names in path beginning with the letter "s".

searchPattern cannot end in two periods ("..") or contain two periods ("..") followed by DirectorySeparatorChar or AltDirectorySeparatorChar, nor can it contain any invalid characters. You can query for invalid characters by using the GetInvalidPathChars method.

Note

When you use the asterisk wildcard character in a searchPattern such as "*.txt", the number of characters in the specified extension affects the search as follows:

  • If the specified extension is exactly three characters long, the method returns files with extensions that begin with the specified extension. For example, "*.xls" returns both "book.xls" and "book.xlsx".
  • In all other cases, the method returns files that exactly match the specified extension. For example, "*.ai" returns "file.ai" but not "file.aif".

When you use the question mark wildcard character, this method returns only files that match the specified file extension. For example, given two files, "file1.txt" and "file1.txtother", in a directory, a search pattern of "file?.txt" returns just the first file, whereas a search pattern of "file*.txt" returns both files.

The path parameter is permitted to specify relative or absolute path information. Relative path information is interpreted as relative to the current working directory. To obtain the current working directory, see GetCurrentDirectory.

The case-sensitivity of the path parameter corresponds to that of the file system on which the code is running. For example, it's case-insensitive on NTFS (the default Windows file system) and case-sensitive on Linux file systems.

For a list of common I/O tasks, see Common I/O Tasks.

See also

Applies to

.NET 10 and other versions
Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0

GetFileSystemEntries(String, String, EnumerationOptions)

Source:
Directory.cs
Source:
Directory.cs
Source:
Directory.cs

Returns an array of file names and directory names that match a search pattern and enumeration options in a specified path.

C#
public static string[] GetFileSystemEntries(string path, string searchPattern, System.IO.EnumerationOptions enumerationOptions);

Parameters

path
String

The relative or absolute path to the directory to search. This string is not case-sensitive.

searchPattern
String

The search string to match against the names of files and directories in path. This parameter can contain a combination of valid literal and wildcard characters, but it doesn't support regular expressions.

enumerationOptions
EnumerationOptions

An object that describes the search and enumeration configuration to use.

Returns

String[]

An array of file names and directory names that match the specified search pattern and enumeration options, or an empty array if no files or directories are found.

Exceptions

The caller does not have the required permission.

.NET Framework and .NET Core versions older than 2.1: path is a zero-length string, contains only white space, or contains one or more invalid characters. You can query for invalid characters with the GetInvalidPathChars() method.

-or-

searchPattern does not contain a valid pattern.

path or searchPattern is null.

The specified path, file name, or both exceed the system-defined maximum length.

path is a file name.

The specified path is invalid (for example, it is on an unmapped drive).

Remarks

The order of the returned file and directory names is not guaranteed; use the Sort method if a specific sort order is required.

searchPattern can be a combination of literal and wildcard characters, but it doesn't support regular expressions. The following wildcard specifiers are permitted in searchPattern.

Wildcard specifier Matches
* (asterisk) Zero or more characters in that position.
? (question mark) Exactly one character in that position.

Characters other than the wildcard are literal characters. For example, the searchPattern string "*t" searches for all names in path ending with the letter "t". The searchPattern string "s*" searches for all names in path beginning with the letter "s".

searchPattern cannot end in two periods ("..") or contain two periods ("..") followed by DirectorySeparatorChar or AltDirectorySeparatorChar, nor can it contain any invalid characters. You can query for invalid characters by using the GetInvalidPathChars method.

Note

When you use the asterisk wildcard character in a searchPattern such as "*.txt", the number of characters in the specified extension affects the search as follows:

  • If the specified extension is exactly three characters long, the method returns files with extensions that begin with the specified extension. For example, "*.xls" returns both "book.xls" and "book.xlsx".
  • In all other cases, the method returns files that exactly match the specified extension. For example, "*.ai" returns "file.ai" but not "file.aif".

When you use the question mark wildcard character, this method returns only files that match the specified file extension. For example, given two files, "file1.txt" and "file1.txtother", in a directory, a search pattern of "file?.txt" returns just the first file, whereas a search pattern of "file*.txt" returns both files.

The path parameter is permitted to specify relative or absolute path information. Relative path information is interpreted as relative to the current working directory. To obtain the current working directory, see GetCurrentDirectory.

The case-sensitivity of the path parameter corresponds to that of the file system on which the code is running. For example, it's case-insensitive on NTFS (the default Windows file system) and case-sensitive on Linux file systems.

For a list of common I/O tasks, see Common I/O Tasks.

Applies to

.NET 10 and other versions
Product Versions
.NET Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Standard 2.1

GetFileSystemEntries(String, String, SearchOption)

Source:
Directory.cs
Source:
Directory.cs
Source:
Directory.cs

Returns an array of all the file names and directory names that match a search pattern in a specified path, and optionally searches subdirectories.

C#
public static string[] GetFileSystemEntries(string path, string searchPattern, System.IO.SearchOption searchOption);

Parameters

path
String

The relative or absolute path to the directory to search. This string is not case-sensitive.

searchPattern
String

The search string to match against the names of files and directories in path. This parameter can contain a combination of valid literal path and wildcard (* and ?) characters, but it doesn't support regular expressions.

searchOption
SearchOption

One of the enumeration values that specifies whether the search operation should include only the current directory or should include all subdirectories. The default value is TopDirectoryOnly.

Returns

String[]

An array of file the file names and directory names that match the specified search criteria, or an empty array if no files or directories are found.

Exceptions

.NET Framework and .NET Core versions older than 2.1: path is a zero-length string, contains only white space, or contains invalid characters. You can query for invalid characters by using the GetInvalidPathChars() method.

-or-

searchPattern does not contain a valid pattern.

path is null.

-or-

searchPattern is null.

searchOption is not a valid SearchOption value.

path is invalid, such as referring to an unmapped drive.

path is a file name.

The specified path, file name, or combined exceed the system-defined maximum length.

The caller does not have the required permission.

The caller does not have the required permission.

Remarks

The order of the returned file and directory names is not guaranteed; use the Sort method if a specific sort order is required.

searchPattern can be a combination of literal and wildcard characters, but it doesn't support regular expressions. The following wildcard specifiers are permitted in searchPattern.

Wildcard specifier Matches
* (asterisk) Zero or more characters in that position.
? (question mark) Exactly one character in that position.

Characters other than the wildcard are literal characters. For example, the searchPattern string "*t" searches for all names in path ending with the letter "t". The searchPattern string "s*" searches for all names in path beginning with the letter "s".

searchPattern cannot end in two periods ("..") or contain two periods ("..") followed by DirectorySeparatorChar or AltDirectorySeparatorChar, nor can it contain any invalid characters. You can query for invalid characters by using the GetInvalidPathChars method.

Note

When you use the asterisk wildcard character in a searchPattern such as "*.txt", the number of characters in the specified extension affects the search as follows:

  • If the specified extension is exactly three characters long, the method returns files with extensions that begin with the specified extension. For example, "*.xls" returns both "book.xls" and "book.xlsx".
  • In all other cases, the method returns files that exactly match the specified extension. For example, "*.ai" returns "file.ai" but not "file.aif".

When you use the question mark wildcard character, this method returns only files that match the specified file extension. For example, given two files, "file1.txt" and "file1.txtother", in a directory, a search pattern of "file?.txt" returns just the first file, whereas a search pattern of "file*.txt" returns both files.

The EnumerateFileSystemEntries and GetFileSystemEntries methods differ as follows: When you use EnumerateFileSystemEntries, you can start enumerating the collection of entries before the whole collection is returned; when you use GetFileSystemEntries, you must wait for the whole array of entries to be returned before you can access the array. Therefore, when you are working with many files and directories, EnumerateFileSystemEntries can be more efficient.

You can specify relative path information with the path parameter. Relative path information is interpreted as relative to the current working directory, which you can determine by using the GetCurrentDirectory method.

See also

Applies to

.NET 10 and other versions
Product Versions
.NET Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 1.3, 1.4, 1.6, 2.0, 2.1
UWP 10.0