StreamReader Constructor (Stream^, Encoding^)

 
System_CAPS_noteNote

The .NET API Reference documentation has a new home. Visit the .NET API Browser on docs.microsoft.com to see the new experience.

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)

public:
StreamReader(
	Stream^ stream,
	Encoding^ encoding
)

Parameters

stream
Type: System.IO::Stream^

The stream to be read.

encoding
Type: System.Text::Encoding^

The character encoding to use.

Exception Condition
ArgumentException

stream does not support reading.

ArgumentNullException

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.

System_CAPS_cautionCaution

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.

void getNewStreamReader()
{

   //Get a new StreamReader in ASCII format from a
   //file using a buffer and byte order mark detection
   StreamReader^ srAsciiFromFileFalse512 = gcnew 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 = gcnew StreamReader(  "C:\\Temp\\Test.txt",System::Text::Encoding::ASCII,false );

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

   //Get a new StreamReader from a
   //file with byte order mark detection = false
   StreamReader^ srFromFileFalse = gcnew StreamReader(  "C:\\Temp\\Test.txt",false );

   //Get a new StreamReader from a file
   StreamReader^ srFromFile = gcnew 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 = gcnew StreamReader( 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 = gcnew StreamReader( File::OpenRead(  "C:\\Temp\\Test.txt" ),System::Text::Encoding::ASCII,false );

   //Get a new StreamReader in ASCII format from a FileStream
   StreamReader^ srAsciiFromStream = gcnew StreamReader( 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 = gcnew StreamReader( File::OpenRead(  "C:\\Temp\\Test.txt" ),false );

   //Get a new StreamReader from a FileStream
   StreamReader^ srFromStream = gcnew StreamReader( File::OpenRead(  "C:\\Temp\\Test.txt" ) );
}


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