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DirectoryInfo.EnumerateFileSystemInfos Method (String, SearchOption)

Returns an enumerable collection of file system information that matches a specified search pattern and search subdirectory option.

Namespace:  System.IO
Assembly:  mscorlib (in mscorlib.dll)

public IEnumerable<FileSystemInfo> EnumerateFileSystemInfos(
	string searchPattern,
	SearchOption searchOption


Type: System.String
The search string. The default pattern is "*", which returns all files or directories.
Type: System.IO.SearchOption
One of the enumeration values that specifies whether the search operation should include only the current directory or all subdirectories. The default value is TopDirectoryOnly.

Return Value

Type: System.Collections.Generic.IEnumerable<FileSystemInfo>
An enumerable collection of file system information objects that matches searchPattern and searchOption.


searchPattern is null.


searchOption is not a valid SearchOption value.


The path encapsulated in the FileSystemInfo object is invalid (for example, it is on an unmapped drive).


The caller does not have the required permission.

The following wildcard specifiers are permitted in the searchPattern parameter.

Wildcard character



Zero or more characters.


Exactly one character.

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

This method pre-populates the values of the following FileSystemInfo properties:

The returned collection is not cached; each call to the GetEnumerator method on the collection will start a new enumeration.

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.