C#

class pinger
{
   public static int PingsOutstanding = 0;
                    
   public string IP;
   
   public void PingIt()
   {
      try
         {
            //keep count of our pings
            System.Threading.Interlocked.Increment(ref PingsOutstanding);
            Ping ping = new Ping();
            ping.Send(IP, 100);
         }
         catch (Exception e)
         {
            //do really secret stuff
         }
         finally
         {
            System.Threading.Interlocked.Decrement(ref PingsOutstanding);
         }
     }
  }   


//snip loads of stuff to show just the loop to fire off the threads

foreach (string ipAddress in _check.GroupData) //a list of IP Addresses                
{
   //create a pinger class
   pinger p = new pinger();
   p.IP = str;//set the IP address in a nice public member.....demo code - honest!

   //create a new thread and launch the ping
   new System.Threading.Thread(new System.Threading.ThreadStart(p.PingIt)).Start();
}


//keep checking the Pinger static count
while (pinger.PingsOutstanding > 0)
{
   //we're not done yet..
  System.Threading.Thread.Sleep(500);
}
//

Malcolm Smart wrote:

It seems the ASync call of Ping doesn't like havnig hundreds of them kicking about.

oXL = new Excel.Application();
oXL.Visible = true;

//Get a new workbook.
oWB = (Excel._Workbook)(oXL.Workbooks.Add( Missing.Value ));
oSheet = (Excel._Worksheet)oWB.ActiveSheet;