File.Open Method (String, FileMode, FileAccess)
Opens a FileStream on the specified path, with the specified mode and access.
Assembly: mscorlib (in mscorlib.dll)
- Type: System.String
The file to open.
- 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.
path is a zero-length string, contains only white space, or contains one or more invalid characters as defined by GetInvalidPathChars.
access specified Read and mode specified Create, CreateNew, Truncate, or Append.
path is null.
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.
The specified path is invalid, (for example, it is on an unmapped drive).
An I/O error occurred while opening the file.
path specified a file that is read-only and access is not Read.
path specified a directory.
The caller does not have the required permission.
mode or access specified an invalid value.
The file specified in path was not found.
path is in an invalid format.