Creating a Service Object Sample (POS for .NET v1.12 SDK Documentation)
2/27/2008
Previous topics explained how to create a basic Service Object template with Plug and Play support. This section adds how to create a limited sample with the following new features:
- Necessary abstract methods are implemented so that the sample will compile successfully.
- The Service Object will be recognized by applications using PosExplorer, for example, the POS for .NET Test Application included with the SDK.
- Applications may now invoke methods on the Service Object or access properties, although no useful results will be returned.
Requirements
To compile this sample, your project has to have the correct references and global attributes.
Example
using System;
using Microsoft.PointOfService;
using Microsoft.PointOfService.BaseServiceObjects;
namespace Samples.ServiceObjects.MSR
{
[HardwareId(@"HID\Vid_05e0&Pid_038a", @"HID\Vid_05e0&Pid_038a")]
[ServiceObject(DeviceType.Msr,
"SampleMsr",
"Sample Msr Service Object",
1,
9)]
public class SampleMsr : MsrBase
{
// String returned from CheckHealth
private string MyHealthText;
public SampleMsr()
{
// Initialize device capability properties.
Properties.CapIso = true;
Properties.CapTransmitSentinels = true;
Properties.DeviceDescription = "Sample MSR";
// Initialize other class variables.
MyHealthText = "";
}
~SampleMsr()
{
Dispose(false);
}
// Release any resources managed by this object.
protected override void Dispose(bool disposing)
{
try
{
// Your code here.
}
finally
{
// Must call base class Dispose.
base.Dispose(disposing);
}
}
#region PosCommon overrides
// Returns the result of the last call to CheckHealth().
public override string CheckHealthText
{
get
{
// MsrBasic.VerifyState(mustBeClaimed,
// mustBeEnabled). This may throw an exception.
VerifyState(false, false);
return MyHealthText;
}
}
public override string CheckHealth(
HealthCheckLevel level)
{
// Verify that device is open, claimed, and enabled.
VerifyState(true, true);
// Your code here:
// check the health of the device and return a
// descriptive string.
// Cache result in the CheckHealthText property.
MyHealthText = "Ok";
return MyHealthText;
}
public override DirectIOData DirectIO(
int command,
int data,
object obj)
{
// Verify that device is open.
VerifyState(false, false);
return new DirectIOData(data, obj);
}
#endregion // PosCommon overrides
#region MsrBasic Overrides
protected override MsrFieldData ParseMsrFieldData(
byte[] track1Data,
byte[] track2Data,
byte[] track3Data,
byte[] track4Data,
CardType cardType)
{
// Your code here:
// Implement this method to parse track data
// into fields which will be returned as
// properties to the application
// (for example, FirstName,
// AccountNumber, etc.)
return new MsrFieldData();
}
protected override MsrTrackData ParseMsrTrackData(
byte[] track1Data,
byte[] track2Data,
byte[] track3Data,
byte[] track4Data,
CardType cardType)
{
// Your code here:
// Implement this method to convert raw track data.
return new MsrTrackData();
}
#endregion
}
}
In order to simplify this sample, the code does not implement any globalization features. For example, the value for Properties.DeviceDescription would typically be read from a localized strings resource file.
See Also
Tasks
Adding Plug and Play Support
Introducing Service Object Reader Threads