c# - Unexpected output from checking if mouse within control -

i implementing custom drag , drop interface winform buttons , after viewing several solutions on how obtain mouse position , check against control bound have not been able work.

i have tried:

button.clientrectangle.contains(pointtoclient(cursor.position)) 

and

button.clientrectangle.contains(pointtoclient(control.mouseposition)) 

both of these have failed work. checking mouse bounds seem simple operation, stumped.

my speculation of unexpected values are:

1. process of obtaining cursor position may in wrong corner of cursor image
2. method/function not work on buttons reason

you using wrong object reference, calculating mouse position relative form instead of button. , writing in way make hard debug. fix:

var pos = button.pointtoclient(cursor.position); system.diagnostics.debug.writeline(pos);         // easy if (button.clientrectangle.contains(pos)) {     // etc...         }