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StreamReader.StreamReader(Stream, Boolean) Constructor

Initializes a new instance of the StreamReader class for the specified stream, with the specified byte order mark detection option.

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

public StreamReader (
	Stream stream,
	bool detectEncodingFromByteOrderMarks
)
public StreamReader (
	Stream stream, 
	boolean detectEncodingFromByteOrderMarks
)
public function StreamReader (
	stream : Stream, 
	detectEncodingFromByteOrderMarks : boolean
)
Not applicable.

Parameters

stream

The stream to be read.

detectEncodingFromByteOrderMarks

Indicates whether to look for byte order marks at the beginning of the file.

Exception typeCondition

ArgumentException

stream does not support reading.

ArgumentNullException

stream is a null reference (Nothing in Visual Basic).

This constructor initializes the encoding to UTF8Encoding, the BaseStream property using the stream parameter, and the internal buffer to the default size.

The detectEncodingFromByteOrderMarks parameter detects 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. See the Encoding.GetPreamble method for more information.

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"));
}

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.get_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.get_ASCII(), false);

    //Get a new StreamReader in ASCII format from a file 
    StreamReader srAsciiFromFile =
        new StreamReader("C:\\Temp\\Test.txt",
        System.Text.Encoding.get_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.get_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.get_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.get_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"))));
} //GetNewStreamReader

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

XNA Framework

Supported in: 1.0

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