C# windows programing

Question

wht is meant by object sender,EventArgs e in c# windows prgmng?

Krishna Rajput Singh · Answer

https://msdn.microsoft.com/en-us/library/360kwx3z(v=vs.90).aspx http://www.c-sharpcorner.com/uploadfile/puranindia/windows-programming-using-C-Sharp/ http://csharp.net-informations.com/gui/cs_forms.htm

Ehsan Sajjad · Answer

Let me explain you with an example from my code base, we have a logger class and wheeever log method is called we fire our own event named LoggerLogged and in which we pass on object the current object using this keyword and the message in event args like: public class ProcessLogger { public event EventHandler OnLoggerLogged; public void WriteLog( string message) { //samemessagetosomefileorDB if ( this .OnLoggerLogged!= null ) //ifsomeonesubsribeeventthenfire OnLoggerLogged( this , new LoggerLoggedEventArgs(message)); } } and here is our custom LoggerLoggedEventArgs class : public class LoggerLoggedEventArgs:EventArgs { public LoggerLoggedEventArgs( string message) { Message=message; } public string Message{ get ; private set ;} } and in my windows form we register it : this .Logger.OnLoggerLogged+= new EventHandler (Logger_OnLoggerLogged); Now when logger class Log method is called event is fired in our form and we have in first parameter the object which raised the event and eventargs we get the message that was logged and then we display it on form : void Logger_OnLoggerLogged( object sender,CRERadialDemographics.Logging.LoggerLoggedEventArgse) { varmessage=e.Message; //nowuseit } I hope it helps.

Ritesh Singh · Answer

The sender is the control that the action is for (say OnClick, it's the button). The EventArgs are arguments that the implementor of this event may find useful. With OnClick it contains nothing good, but in some events, like say in a GridView 'SelectedIndexChanged', it will contain the new index, or some other useful data.