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SerialPort.Read Method (Byte[], Int32, Int32)

Reads a number of bytes from the SerialPort input buffer and writes those bytes into a byte array at the specified offset.

Namespace: System.IO.Ports
Assembly: System (in system.dll)

public int Read (
	byte[] buffer,
	int offset,
	int count
)
public int Read (
	byte[] buffer, 
	int offset, 
	int count
)
public function Read (
	buffer : byte[], 
	offset : int, 
	count : int
) : int
Not applicable.

Parameters

buffer

The byte array to write the input to.

offset

The offset in the buffer array to begin writing.

count

The number of bytes to read.

Return Value

The number of bytes read.

Exception typeCondition

ArgumentNullException

The buffer passed is a null reference (Nothing in Visual Basic).

InvalidOperationException

The specified port is not open.

ArgumentOutOfRangeException

The offset or count parameters are outside a valid region of the buffer being passed. Either offset or count is less than zero.

ArgumentException

offset plus count is greater than the length of the buffer.

TimeoutException

No bytes were available to read.

If it is necessary to switch between reading text and reading binary data from the stream, select a protocol that carefully defines the boundary between text and binary data, such as manually reading bytes and decoding the data.

NoteNote:

Because the SerialPort class buffers data, and the stream contained in the BaseStream property does not, the two might conflict about how many bytes are available to read. The BytesToRead property can indicate that there are bytes to read, but these bytes might not be accessible to the stream contained in the BaseStream property because they have been buffered to the SerialPort class.

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

.NET Compact Framework

Supported in: 2.0

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