lambda - Event is not Called C# -

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i'm making nfc library, need raise event, when card has been read.

in mainproject call library this:

reader = new nfcreader();     if (reader.initialize())     {         reader.uidreceived += (s, args) =>              displaytext(string.format("uid received: {0}", args.uid));     }

my library:

public class nfcreader {     private scardmonitor monitor;     public event eventhandler<nfcreadereventargs> uidreceived;      public bool initialize()     {         // when card inserted, event raised         // want read uid of card          monitor = new scardmonitor(new scardcontext(), scardscope.system);         monitor.cardinserted += (s,a) => getuid(a.readername);         return true;     }      private void getuid(string readername)     {         string uid = myuidgetter(readername);         onuidreceived(uid);     }      private void onuidreceived(string uid)     {         var handler = uidreceived;         if (handler == null)         {             handler(this, new nfcreadereventargs(uid));         }     } }

the debugger steps through handler(this, new nfcreadereventargs(uid));, displaytext method doesn't called. ideas?

i guess typo check handler null? ;)

maybe initialize return false. , debugger steps through because won't call anything. made sure if.

i recommend use handler != null instead , make sure initialize returns true.


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