StreamReader Constructor (String, Encoding)
Initializes a new instance of the StreamReader class for the specified file name, with the specified character encoding.
Assembly: mscorlib (in mscorlib.dll)
Parameters
- path
- Type: System.String
The complete file path to be read.
- encoding
- Type: System.Text.Encoding
The character encoding to use.
| Exception | Condition |
|---|---|
| ArgumentException | path is an empty string (""). |
| ArgumentNullException | path or encoding is null. |
| FileNotFoundException | The file cannot be found. |
| DirectoryNotFoundException | The specified path is invalid, such as being on an unmapped drive. |
| NotSupportedException | path includes an incorrect or invalid syntax for file name, directory name, or volume label. |
This constructor initializes the encoding as specified by the encoding parameter, and the internal buffer size to 1024 bytes. The StreamReader object attempts to detect the encoding by looking at the first three bytes of the stream. It automatically recognizes UTF-8, little-endian Unicode, and big-endian Unicode text if the file starts with the appropriate byte order marks. Otherwise, the user-provided encoding is used. See the Encoding.GetPreamble method for more information.
The path parameter can be a file name, including a file on a Universal Naming Convention (UNC) share.
The path parameter is not required to be a file stored on disk; it can be any part of a system that supports access using streams.
 Caution |
|---|
When you compile a set of characters with a particular cultural setting and retrieve those same characters with a different cultural setting, the characters might not be interpretable, and could cause an exception to be thrown. |
For a list of common I/O tasks, see Common I/O Tasks.
The following code example demonstrates this StreamReader constructor.
private void getNewStreamReader() { //Get a new StreamReader in ASCII format from a //file using a buffer and byte order mark detection StreamReader srAsciiFromFileFalse512 = new StreamReader("C:\\Temp\\Test.txt", System.Text.Encoding.ASCII, false, 512); //Get a new StreamReader in ASCII format from a //file with byte order mark detection = false StreamReader srAsciiFromFileFalse = new StreamReader("C:\\Temp\\Test.txt", System.Text.Encoding.ASCII, false); //Get a new StreamReader in ASCII format from a file StreamReader srAsciiFromFile = new StreamReader("C:\\Temp\\Test.txt", System.Text.Encoding.ASCII); //Get a new StreamReader from a //file with byte order mark detection = false StreamReader srFromFileFalse = new StreamReader("C:\\Temp\\Test.txt", false); //Get a new StreamReader from a file StreamReader srFromFile = new StreamReader("C:\\Temp\\Test.txt"); //Get a new StreamReader in ASCII format from a //FileStream with byte order mark detection = false and a buffer StreamReader srAsciiFromStreamFalse512 = new StreamReader( (System.IO.Stream)File.OpenRead("C:\\Temp\\Test.txt"), System.Text.Encoding.ASCII, false, 512); //Get a new StreamReader in ASCII format from a //FileStream with byte order mark detection = false StreamReader srAsciiFromStreamFalse = new StreamReader( (System.IO.Stream)File.OpenRead("C:\\Temp\\Test.txt"), System.Text.Encoding.ASCII, false); //Get a new StreamReader in ASCII format from a FileStream StreamReader srAsciiFromStream = new StreamReader( (System.IO.Stream)File.OpenRead("C:\\Temp\\Test.txt"), System.Text.Encoding.ASCII); //Get a new StreamReader from a //FileStream with byte order mark detection = false StreamReader srFromStreamFalse = new StreamReader( (System.IO.Stream)File.OpenRead("C:\\Temp\\Test.txt"), false); //Get a new StreamReader from a FileStream StreamReader srFromStream = new StreamReader( (System.IO.Stream)File.OpenRead("C:\\Temp\\Test.txt")); }
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
