c# - Cannot find RowClickEventArgs in DevexpressGridView -

i'm new devexpressgridview.

i have dev grid in webpage, , want handle rowclick event like:

private void gridview1_rowclick(object sender, rowclickeventargs e) {     if(a row selected)// how???         button1.visible=true; } 

but when has error: "cannot resolve symbol rowclickeventargs", first time know devexpress. wonder if rowclickeventargs syntax wrong??? i've tried find solution searching google many times, still cannot right thing.

can give me right syntax???

and 1 more question, how can check " there row selected ?"

help!

so this:

private void gridview1_click(object sender, eventargs e) {     system.data.datarow row = gridview2.getdatarow(gridview2.focusedrowhandle);     if(row[0].tostring() == "")     {           //your logic     }  } 

gridview2 main view.