File.Open Method (String, FileMode, FileAccess, FileShare)
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Opens a FileStream on the specified path, having the specified mode with read, write, or read/write access and the specified sharing option.
Assembly: mscorlib (in mscorlib.dll)
'Declaration Public Shared Function Open ( _ path As String, _ mode As FileMode, _ access As FileAccess, _ share As FileShare _ ) As FileStream
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.FileStreamA FileStream on the specified path, having the specified mode with read, write, or read/write access and the specified sharing option.
| Exception | Condition |
|---|---|
| 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 Nothing. |
| 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.