c# - get value from selected row datagridview -

i need value datagridview.

int selectedrowindex = dgvtable.selectedcells[0].rowindex;  datagridviewrow selectedrow = dgvtable.rows[selectedrowindex];  string id = selectedrow.cells["f_id"].value.tostring(); 

but value of next row (row_index + 1). variable selectedrowindex correct, value of selectedrow wrong.