Get the selected rows in datagridview

Question

 How to get the selected row(s) in datagridview from clicking the other button in window form?

 

I want to delete the selected row(s) in datagridview by clicking "DELETE" button in my window form application. 

 

Can anyone help me how to do? Thanks a lot for viewing my question and please solve my problem to delete the selected rows by clicking the button in my window form.