Opens an existing file for reading.
Assembly: mscorlib (in mscorlib.dll)
path is a zero-length string, contains only white space, or contains one or more invalid characters as defined by InvalidPathChars.
path is a null reference (Nothing in Visual Basic).
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).
path specified a directory.
The caller does not have the required permission.
The file specified in path was not found.
path is in an invalid format.
The path parameter is permitted to specify relative or absolute path information. Relative path information is interpreted as relative to the current working directory. To obtain the current working directory, see GetCurrentDirectory.
For a list of common I/O tasks, see Common I/O Tasks.
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.