c# - Fastest way checking for COM ports -


i need check available com ports in application:

i created 2 ways this.

method 1:

public list<string> getallportsforeach() {      var allports = new list<string>();      foreach (string portname in system.io.ports.serialport.getportnames())      {            allports.add(portname);      }      return allports; }

method 2:

public list<string> getallportsforloop() {       var allports = new list<string>();        (int = 1; <= 16; i++)        {            string comportname = "com" + convert.tostring(i);            serialport sp = new serialport(comportname);            try            {                sp.open();                allports.add(comportname);                               sp.close();             }             catch             {             }         }         return allports; }

which fastest? should use , why?

the 1st one. reads available port names registry. more precise, enough use serialport.getportnames, if you're not planning add custom port name list.

the 2nd one:

  • limited port number (port name can "com20", total numbers of ports in system be, e.g., 4)
  • exception-based (this ugly , slower).

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