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Stream.Read Method

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

When overridden in a derived class, reads a sequence of bytes from the current stream and advances the position within the stream by the number of bytes read.

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

Syntax

'Declaration
Public MustOverride Function Read ( _
    <OutAttribute> buffer As Byte(), _
    offset As Integer, _
    count As Integer _
) As Integer
public abstract int Read(
    byte[] buffer,
    int offset,
    int count
)

Parameters

  • buffer
    Type: array<System.Byte[]
    An array of bytes. When this method returns, the buffer contains the specified byte array with the values between offset and (offset + count - 1) replaced by the bytes read from the current source.
  • offset
    Type: System.Int32
    The zero-based byte offset in buffer at which to begin storing the data read from the current stream.
  • count
    Type: System.Int32
    The maximum number of bytes to be read from the current stream.

Return Value

Type: System.Int32
The total number of bytes read into the buffer. This can be less than the number of bytes requested if that many bytes are not currently available, or zero (0) if the end of the stream has been reached.

Exceptions

Exception Condition
ArgumentException

The sum of offset and count is larger than the buffer length.

ArgumentNullException

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

ArgumentOutOfRangeException

offset or count is negative.

IOException

An I/O error occurs.

NotSupportedException

The stream does not support reading.

ObjectDisposedException

Methods were called after the stream was closed.

Remarks

Use the CanRead property to determine whether the current instance supports reading.

Implementations of this method read a maximum of count bytes from the current stream and store them in buffer beginning at offset. The current position within the stream is advanced by the number of bytes read; however, if an exception occurs, the current position within the stream remains unchanged. Implementations return the number of bytes read. The return value is zero only if the position is currently at the end of the stream. The implementation will block until at least one byte of data can be read, in the event that no data is available. Read returns 0 only when there is no more data in the stream and no more is expected (such as a closed socket or end of file). An implementation is free to return fewer bytes than requested even if the end of the stream has not been reached.

Use BinaryReader for reading primitive data types.

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.

See Also

Reference