StreamReader Constructor (Stream, Encoding)


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Initializes a new instance of the StreamReader class for the specified stream, with the specified character encoding.

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

new : 
        stream:Stream *
        encoding:Encoding -> StreamReader


Type: System.IO.Stream

The stream to be read.

Type: System.Text.Encoding

The character encoding to use.

Exception Condition

stream does not support reading.


stream or encoding is null.

The character encoding is set by the encoding parameter, and the buffer size is set 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 StreamReader object calls Dispose() on the provided Stream object when StreamReader.Dispose is called.


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.

No code example is currently available or this language may not be supported.

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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