IsolatedStorageFileStream::BeginRead Method (array<Byte>^, Int32, Int32, AsyncCallback^, Object^)
Begins an asynchronous read.
Assembly: mscorlib (in mscorlib.dll)
public: [HostProtectionAttribute(SecurityAction::LinkDemand, ExternalThreading = true)] virtual IAsyncResult^ BeginRead( array<unsigned char>^ buffer, int offset, int numBytes, AsyncCallback^ userCallback, Object^ stateObject ) override
Parameters
- buffer
-
Type:
array<System::Byte>^
The buffer to read data into.
- offset
-
Type:
System::Int32
The byte offset in buffer at which to begin reading.
- numBytes
-
Type:
System::Int32
The maximum number of bytes to read.
- userCallback
-
Type:
System::AsyncCallback^
The method to call when the asynchronous read operation is completed. This parameter is optional.
- stateObject
-
Type:
System::Object^
The status of the asynchronous read.
Return Value
Type: System::IAsyncResult^An IAsyncResult object that represents the asynchronous read, which is possibly still pending. This IAsyncResult must be passed to this stream's EndRead method to determine how many bytes were read. This can be done either by the same code that called BeginRead or in a callback passed to BeginRead.
| Exception | Condition |
|---|---|
| IOException | An asynchronous read was attempted past the end of the file. |
The current position in the stream is updated when you issue the asynchronous read or write, not when the I/O operation completes.
You must call EndRead with this IAsyncResult to find out how many bytes were read.
Available since 1.1
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0