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Checks if a packet is available to be read from the device packet stream.
Namespace: Microsoft.SmartDevice.Connectivity
Assembly: Microsoft.SmartDevice.Connectivity (in Microsoft.SmartDevice.Connectivity.dll)
Syntax
'Declaration
Public Function IsPacketAvailable As Boolean
'Usage
Dim instance As DevicePacketStream
Dim returnValue As Boolean
returnValue = instance.IsPacketAvailable()
public bool IsPacketAvailable()
public:
bool IsPacketAvailable()
public function IsPacketAvailable() : boolean
Return Value
Type: System.Boolean
true if there is data ready to be read; otherwise, false.
Exceptions
| Exception | Condition |
|---|---|
| IOException | A COM or IO exception has occurred. |
Remarks
A packet is available when a connected device agent writes a packet to the stream by calling Write.
Examples
' While stream is connected, try to read a packet.
While ps.IsConnected()
If ps.IsPacketAvailable() Then
packet = ps.Read()
While Not packet.IsEndOfPacket()
Select Case packet.ReadDataType()
Case DataType.BoolType
Dim boolValue As Boolean = packet.ReadBool()
Case DataType.ByteArrayType
Dim buffer As Byte() = packet.ReadBytes()
Case DataType.ByteType
Dim byteValue As Byte = packet.ReadByte()
Case DataType.CharType
Dim charValue As Char = packet.ReadChar()
Case DataType.Int32Type
Console.WriteLine("Int32Type: " + packet.ReadInt32().ToString())
Case DataType.StringType
Console.WriteLine("String: " + packet.ReadString())
Case Else
End Select
End While
Exit While
End If
System.Threading.Thread.Sleep(1000)
End While
ps.Close()
device.Disconnect()
// While stream is connected, try to read a packet.
while (ps.IsConnected())
{
if (ps.IsPacketAvailable())
{
packet = ps.Read();
while (!packet.IsEndOfPacket())
{
switch (packet.ReadDataType())
{
case DataType.BoolType:
bool boolValue = packet.ReadBool();
break;
case DataType.ByteArrayType:
byte[] buffer = packet.ReadBytes();
break;
case DataType.ByteType:
byte byteValue = packet.ReadByte();
break;
case DataType.CharType:
char charValue = packet.ReadChar();
break;
case DataType.Int32Type:
Console.WriteLine("Int32Type: " + packet.ReadInt32().ToString());
break;
case DataType.StringType:
Console.WriteLine("String: " + packet.ReadString());
break;
default:
break;
}
}
break;
}
System.Threading.Thread.Sleep(1000);
}
ps.Close();
device.Disconnect();
.NET Framework Security
- Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see Using Libraries from Partially Trusted Code.