c# - Code is WRONG but no error is raised -

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i have written code in form "load" event

        messagebox.show("message 1");         string strconnectionstring = @"data source=hb-vaio\sqlexpress;initial catalog=db1;integrated security=true;pooling=false";         sqlcommand cmdaddpackage = new sqlcommand("addpackage");         sqlconnection con = new sqlconnection();         con.connectionstring = strconnectionstring;          cmdaddpackage.commandtype = commandtype.storedprocedure;         cmdaddpackage.parameters.add(new sqlparameter("@guidoutput",sqldbtype.uniqueidentifier)).direction = parameterdirection.output;          guid gui = (guid) cmdaddpackage.executescalar();   // error should raised there no error         messagebox.show(gui.tostring());         cmdaddpackage.connection.close();         textbox1.text = gui.tostring();         messagebox.show("end");

i know code wrong! , should raise "cannot open database "db1" requested login. login failed. login failed user 'hb-vaio\sony'." in line 8, when run program no error raised, first message box pops out there no sign of second , third message box , form loads successfully.

the wrong things code these :

  • my database name "db" in code used "db1".

  • connection cmdaddpackage not set.

when add same code button1_click event, shows error.

can me why happens ?

i didn't find answer :(

what ui frameworks use? .net ui frameworks indeed provide "load" events, happen silence exceptions happen during even-handlers, "to provide better ui experience end user".

you can check if exceptions thrown in output panel under debugger. if see "first chance exception" - here have it, ui framework "quiet one".

add try-catch, or add application.unhandledexception eventhandler, , try bear quiet ui..

if recall correctly, wpf liked silently skip exceptions, while winforms tended crash instantly. may wrong here.


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