File.Open Method (String, FileMode, FileAccess, FileShare)

May 11, 2014

Opens a FileStream on the specified path, having the specified mode with read, write, or read/write access and the specified sharing option.

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

public static FileStream Open(
	string path,
	FileMode mode,
	FileAccess access,
	FileShare share
)

Parameters

path
Type: System.String
The file to open.
mode
Type: System.IO.FileMode
A FileMode value that specifies whether a file is created if one does not exist, and determines whether the contents of existing files are retained or overwritten.
access
Type: System.IO.FileAccess
A FileAccess value that specifies the operations that can be performed on the file.
share
Type: System.IO.FileShare
A FileShare value specifying the type of access other threads have to the file.

Return Value

Type: System.IO.FileStream
A FileStream on the specified path, having the specified mode with read, write, or read/write access and the specified sharing option.

ExceptionCondition
ArgumentException

path is a zero-length string, contains only white space, or contains one or more invalid characters as defined by GetInvalidPathChars.

-or-

access specified Read and mode specified Create, CreateNew, Truncate, or Append.

ArgumentNullException

path is null.

PathTooLongException

The specified path, file name, or both exceed the system-defined maximum length. For example, on Windows-based platforms, paths must be less than 248 characters, and file names must be less than 260 characters.

DirectoryNotFoundException

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

IOException

An I/O error occurred while opening the file.

UnauthorizedAccessException

path specified a file that is read-only and access is not Read.

-or-

path specified a directory.

-or-

The caller does not have the required permission.

ArgumentOutOfRangeException

mode, access, or share specified an invalid value.

FileNotFoundException

The file specified in path was not found.

NotSupportedException

path is in an invalid format.

Version Notes

Windows Phone

 This member has a SecurityCriticalAttribute attribute. This attribute restricts this member to internal use. Application code that uses this member throws a MethodAccessException.

Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

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