Don't know if there is a better way to do this, so that is the reason for the question. I can check if a service exists on a particular machine with the following code:
bool DoesServiceExist(string serviceName, string machineName)
{
ServiceController controller = null;
try
{
controller = new ServiceController(serviceName, machineName);
controller.Status;
return true;
}
catch(InvalidOperationException)
{
return false;
}
finally
{
if (controller != null)
{
controller.Dispose();
}
}
}
but this seems like an ineffecient solution to me (due to the exception handling). Is there a better way to check if a service exists. Note - I have recently switched to .Net 4.0 so if someone knows of a better solution in 4.0 that would be acceptable.
EDIT:
Here is a sample c# console app to test the performance of my example as well as the GetServices code sample. In my testing I found that the GetServices is much more performative in the case where the service does not exist, but is twice as slow when the service does exist:
static void Main(string[] args)
{
string serviceName = string.Empty;
string machineName = string.Empty;
var sw = new Stopwatch();
sw.Reset();
sw.Start();
for (int i = 0; i < 1000; i++)
{
ServiceExistsException(serviceName, machineName);
}
sw.Stop();
Console.WriteLine("Elapsed time: " + sw.ElapsedMilliseconds.ToString());
sw.Reset();
sw.Start();
for (int i = 0; i < 1000; i++)
{
ServiceExistsGetList(serviceName, machineName);
}
sw.Stop();
Console.WriteLine("Elapsed time: " + sw.ElapsedMilliseconds.ToString());
Console.WriteLine("Done");
Console.ReadLine();
}
static bool ServiceExistsException(string serviceName, string machineName)
{
ServiceController controller = null;
try
{
controller = new ServiceController(serviceName, machineName);
string name = controller.DisplayName;
return true;
}
catch (InvalidOperationException)
{
return false;
}
finally
{
if (controller != null)
{
controller.Dispose();
}
}
}
static bool ServiceExistsGetList(string serviceName, string machineName)
{
ServiceController[] services = null;
try
{
services = ServiceController.GetServices(machineName);
var service = services.FirstOrDefault(s => s.ServiceName == serviceName);
return service != null;
}
finally
{
if (services != null)
{
foreach (ServiceController controller in services)
{
controller.Dispose();
}
}
}
}
}
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