SetAccessControl Method

FileStream.SetAccessControl Method (FileSecurity)


Applies access control list (ACL) entries described by a FileSecurity object to the file described by the current FileStream object.

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

public void SetAccessControl(
	FileSecurity fileSecurity


Type: System.Security.AccessControl.FileSecurity

An object that describes an ACL entry to apply to the current file.

Exception Condition

The file is closed.


The fileSecurity parameter is null.


The file could not be found or modified.


The current process does not have access to open the file.

While the FileStream class and SetAccessControl can be used on an existing file, consider using the File.SetAccessControl method as it is easier to use.

The SetAccessControl method applies access control list (ACL) entries to a file that represents the noninherited ACL list.


The ACL specified for the fileSecurity parameter replaces the existing ACL for the file. To add permissions for a new user, use the GetAccessControl method to obtain the existing ACL, modify it, and then use SetAccessControl to apply it back to the file.

An ACL describes individuals and/or groups who have, or do not have, rights to specific actions on the given file. For more information, see How to: Add or Remove Access Control List Entries.

.NET Framework
Available since 2.0
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