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FileStream.BeginRead(Byte[], Int32, Int32, AsyncCallback, Object) Method

Definition

Namespace:
System.IO
Assemblies:
netstandard.dll, System.Runtime.dll
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll
Source:
FileStream.cs
Source:
FileStream.cs
Source:
FileStream.cs
Source:
FileStream.cs
Source:
FileStream.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Begins an asynchronous read operation. Consider using ReadAsync(Byte[], Int32, Int32, CancellationToken) instead.

public:
 override IAsyncResult ^ BeginRead(cli::array <System::Byte> ^ buffer, int offset, int count, AsyncCallback ^ callback, System::Object ^ state);
public:
 override IAsyncResult ^ BeginRead(cli::array <System::Byte> ^ array, int offset, int numBytes, AsyncCallback ^ callback, System::Object ^ state);
public:
 override IAsyncResult ^ BeginRead(cli::array <System::Byte> ^ array, int offset, int numBytes, AsyncCallback ^ userCallback, System::Object ^ stateObject);
public override IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback? callback, object? state);
public override IAsyncResult BeginRead(byte[] array, int offset, int numBytes, AsyncCallback? callback, object? state);
public override IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback callback, object state);
public override IAsyncResult BeginRead(byte[] array, int offset, int numBytes, AsyncCallback callback, object state);
public override IAsyncResult BeginRead(byte[] array, int offset, int numBytes, AsyncCallback callback, object? state);
public override IAsyncResult BeginRead(byte[] array, int offset, int numBytes, AsyncCallback userCallback, object stateObject);
override this.BeginRead : byte[] * int * int * AsyncCallback * obj -> IAsyncResult
override this.BeginRead : byte[] * int * int * AsyncCallback * obj -> IAsyncResult
override this.BeginRead : byte[] * int * int * AsyncCallback * obj -> IAsyncResult
Public Overrides Function BeginRead (buffer As Byte(), offset As Integer, count As Integer, callback As AsyncCallback, state As Object) As IAsyncResult
Public Overrides Function BeginRead (array As Byte(), offset As Integer, numBytes As Integer, callback As AsyncCallback, state As Object) As IAsyncResult
Public Overrides Function BeginRead (array As Byte(), offset As Integer, numBytes As Integer, userCallback As AsyncCallback, stateObject As Object) As IAsyncResult

Parameters

arraybuffer
Byte[]

The buffer to read data into.

offset
Int32

The byte offset in array at which to begin reading.

numBytescount
Int32

The maximum number of bytes to read.

callbackuserCallback
AsyncCallback

The method to be called when the asynchronous read operation is completed.

statestateObject
Object

A user-provided object that distinguishes this particular asynchronous read request from other requests.

Returns

An object that references the asynchronous read.

Exceptions

The array length minus offset is less than numBytes.

array is null.

offset or numBytes is negative.

An asynchronous read was attempted past the end of the file.

Applies to

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