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StreamReader Constructor (Stream, Boolean)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

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

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

Syntax

'Declaration
Public Sub New ( _
    stream As Stream, _
    detectEncodingFromByteOrderMarks As Boolean _
)
public StreamReader(
    Stream stream,
    bool detectEncodingFromByteOrderMarks
)

Parameters

  • detectEncodingFromByteOrderMarks
    Type: System.Boolean
    true to look for byte order marks at the beginning of the file; otherwise, false to use UTF8 encoding.

Exceptions

Exception Condition
ArgumentException

stream does not support reading.

ArgumentNullException

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

Remarks

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

The StreamReader object calls Stream.Dispose() on the provided Stream object when StreamReader.Dispose is called.

If the detectEncodingFromByteOrderMarks parameter is true, the StreamReader 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. If the detectEncodingFromByteOrderMarks parameter is false, the StreamReader object automatically use UTF-8. See the Encoding.GetPreamble method for more information.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.