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SetLength Method

FileStream.SetLength Method

Sets the length of this stream to the given value.

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

public override void SetLength(
	long value
)

Parameters

value
Type: System.Int64

The new length of the stream.

ExceptionCondition
IOException

An I/O error has occurred.

NotSupportedException

The stream does not support both writing and seeking.

ArgumentOutOfRangeException

Attempted to set the value parameter to less than 0.

This method overrides SetLength.

If the given value is less than the current length of the stream, the stream is truncated. In this scenario, if the current position is greater than the new length, the current position is moved to the last byte of the stream. If the given value is larger than the current length of the stream, the stream is expanded, and the current position remains the same. If the stream is expanded, the contents of the stream between the old and the new length are undefined.

A stream must support both writing and seeking for SetLength to work.

NoteNote

Use the CanWrite property to determine whether the current instance supports writing, and the CanSeek property to determine whether seeking is supported. For additional information, see CanWrite and CanSeek.

For a list of common file and directory operations, see Common I/O Tasks.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8
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