GetValue(TPCANHandle, TPCANParameter, String, UInt32)

PCAN-Basic

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PCAN-Basic Documentation

Retrieves information from a PCAN Channel in text form.

Syntax

Pascal OO

class function GetValue(
    Channel: TPCANHandle;
    Parameter: TPCANParameter;
    StringBuffer: PChar;
    BufferLength: LongWord
    ): TPCANStatus; overload;

[DllImport("PCANBasic.dll", EntryPoint = "CAN_GetValue")]
public static extern TPCANStatus GetValue(
    [MarshalAs(UnmanagedType.U1)]
    TPCANHandle Channel,
    [MarshalAs(UnmanagedType.U1)]
    TPCANParameter Parameter,
    StringBuilder StringBuffer,
    UInt32 BufferLength);

C++ / CLR

[DllImport("PCANBasic.dll", EntryPoint = "CAN_GetValue")]
static TPCANStatus GetValue(
    [MarshalAs(UnmanagedType::U1)]
    TPCANHandle Channel,
    [MarshalAs(UnmanagedType::U1)]
    TPCANParameter Parameter,
    StringBuilder^ StringBuffer,
    UInt32 BufferLength);

Visual Basic

<DllImport("PCANBasic.dll", EntryPoint:="CAN_GetValue")> _
Public Shared Function GetValue( _
    <MarshalAs(UnmanagedType.U1)> _
    ByVal Channel As TPCANHandle, _
    <MarshalAs(UnmanagedType.U1)> _
    ByVal Parameter As TPCANParameter, _
    ByVal StringBuffer As StringBuilder, _
    ByVal BufferLength As UInt32) As TPCANStatus
End Function

Parameters

Parameters	Description
Channel	The handle of a PCAN Channel (see TPCANHandle).
Parameter	The code of the information to be retrieved (see TPCANParameter).
StringBuffer	The buffer to return the required string value.
BufferLength	The length in bytes of the given buffer.

Returns

The return value is a TPCANStatus code. PCAN_ERROR_OK is returned on success. The typical errors in case of failure are:

PCAN_ERROR_ILLPARAMVAL:	Indicates that the parameters passed to the method are invalid. Check the parameter 'StringBuffer'; it should point to a valid null-terminated string buffer.
PCAN_ERROR_INITIALIZE:	Indicates that the given PCAN channel was not found in the list of initialized channels of the calling application.
PCAN_ERROR_ILLPARAMTYPE:	Indicates that the requested information is not available for the given PCAN Channel. Check the value of 'Parameter'; some values are not available for all PCAN-Channels or cannot be read.

Remarks

Use the method GetValue to get information about PCAN environment as parameters like the Message Filter and values like the availability of a PCAN-Channel. Take in account that not all parameters are supported for all PCAN-Channels. The access's type of the parameters can also be different.

More information about the parameters and values that can be read can be found in Parameter Value Definitions.

Example

The following example shows the use of the method GetValue on the channel PCAN_USBBUS1 to get the PCAN-Channel version text. In case of failure, the returned code will be translated to a text (according with the operating system language) in English, German, Italian, French or Spanish, and it will be shown to the user.

Note: It is assumed that the channel was already initialized InitializeFD.

C#:

TPCANStatus result;
StringBuilder strMsg;

strMsg = new StringBuilder(256);

// The version of the PCAN-USB Channel 1 is asked.
//
result = PCANBasic.GetValue(PCANBasic.PCAN_USBBUS1, TPCANParameter.PCAN_CHANNEL_VERSION,strMsg, 256 );
if (result != TPCANStatus.PCAN_ERROR_OK)
{
    // An error occurred, get a text describing the error and show it
    //
    PCANBasic.GetErrorText(result, 0, strMsg);
    MessageBox.Show(strMsg.ToString());
}
else
    // Show the version message
    //
    MessageBox.Show(strMsg.ToString());

C++/CLR:

TPCANStatus result;
StringBuilder^ strMsg;

strMsg = gcnew StringBuilder(256);

// The version of the PCAN-USB Channel 1 is asked.
//
result = PCANBasic::GetValue(PCANBasic::PCAN_USBBUS1, TPCANParameter::PCAN_CHANNEL_VERSION, strMsg, 256);
if (result != TPCANStatus::PCAN_ERROR_OK)
{
    // An error occurred, get a text describing the error and show it
    //
    PCANBasic::GetErrorText(result, 0, strMsg);
    MessageBox::Show(strMsg->ToString());
}
else
    // Show the version message
    //
    MessageBox::Show(strMsg->ToString());

Visual Basic:

Dim result As TPCANStatus
Dim strMsg As StringBuilder

strMsg = New StringBuilder(256)

' The version of the PCAN-USB Channel 1 is asked.
'
result = PCANBasic.GetValue(PCANBasic.PCAN_USBBUS1, TPCANParameter.PCAN_CHANNEL_VERSION, strMsg, 256)
If result <> TPCANStatus.PCAN_ERROR_OK Then
    ' An error occurred, get a text describing the error and show it
    '
    PCANBasic.GetErrorText(result, 0, strMsg)
    MessageBox.Show(strMsg.ToString())
Else
    ' Show the version message
    '
    MessageBox.Show(strMsg.ToString())
End If

Pascal OO:

var
    result: TPCANStatus;
    strMsg: array [0..256] of Char;
begin

    // The version of the PCAN-USB Channel 1 is asked.
    //
    result := TPCANBasic.GetValue(TPCANBasic.PCAN_USBBUS1, PCAN_CHANNEL_VERSION, strMsg, 256);
    If (result <> PCAN_ERROR_OK) Then
    begin
        // An error occurred, get a text describing the error and show it
        //
        TPCANBasic.GetErrorText(result, 0, strMsg);
        MessageBox(0, strMsg, 'Error',MB_OK);
    end
    else
        // Show the version message
        //
        MessageBox(0, strMsg, 'Success',MB_OK);