I'm currently making a payroll system for our thesis and I'm having trouble when it comes to Time In Time Out. Our panel said that we should put only one button and one textbox. How should I do that. Thanks in advance.
You need a timer control and and a single start/stop button. On the first click of the button set the timer to enabled. Show the timer's elapsed time in your textbox. On the next click check if the timer is enabled then measure the timespan between now and when the timer was started.
Full example with code is here: http://markb.co.uk/creating-a-simple-stopwatchtimer-application-with-c-windows-forms.html