EnumerateFiles Method (String, SearchOption)

DirectoryInfo.EnumerateFiles Method (String, SearchOption)


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

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

member EnumerateFiles : 
        searchPattern:string *
        searchOption:SearchOption -> IEnumerable<FileInfo>


Type: System.String

The search string to match against the names of files. This parameter can contain a combination of valid literal path and wildcard (* and ?) characters (see Remarks), but doesn't support regular expressions. The default pattern is "*", which returns all files.

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<FileInfo>

An enumerable collection of files that matches searchPattern and searchOption.

Exception Condition

searchPattern is null.


searchOption is not a valid SearchOption value.


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


The caller does not have the required permission.

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

Wildcard specifier


* (asterisk)

Zero or more characters in that position.

? (question mark)

Zero or one character in that position.

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

The EnumerateFiles and GetFiles methods differ as follows:

  • When you use EnumerateFiles, you can start enumerating the collection of FileInfo objects before the whole collection is returned.

  • When you use GetFiles, you must wait for the whole array of FileInfo objects to be returned before you can access the array.

Therefore, when you are working with many files and directories, EnumerateFiles can be more efficient.

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

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

The following example shows how to enumerate files in a directory by using different search options. The example assumes a directory that has files named log1.txt, log2.txt, test1.txt, test2.txt, test3.txt, and a subdirectory that has a file named SubFile.txt.

No code example is currently available or this language may not be supported.

Universal Windows Platform
Available since 10
.NET Framework
Available since 4.0
Available since 4.0
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